[10] What Robotics related products are there?

CCTV makes a number of small CCD surveillance cameras. Some as small as a pack of cigarettes that sell for less than $300. Small cameras -- 'Pincam' 1.5"x1.5"x.75" pinhole camera for $200. MOD-250 and MOD-275 are all single PC board cameras with wide angle 3.6 mm lenses 514x491V resolution, and composite outputs. Other cameras come in unique enclosures for surveilance (e.g. cigarette packs, clocks, smoke detectors).

Cohu makes a number of solid state cameras including board level and remote head devices. The 1100 series is designed for OEM use. It outputs standard RS-170 with 768x494 CCD resolution. 10cmx4.5cmx1.6cm w/o lens. Other units include the 550 series Intensified Monochrome CCD Camera for low-light applications. The 4110 has digital output (eliminates pixel jitter), The 6X00 series are small monochrome remote head cameras and the 8000 series cameras are color remote head devices. A variety of ouputs are available includeing NTSC, RGB, PAL/Y-C. A high resolution unit, the 8410 series, provides 1134x486 pixels (850 horz TV lines)

DAK sells all kinds of gadgets for the home and business. One device is a security camera that is smaller than a credit card (length and width) and 38mm deep. B/W 251,904 pixels, 60 degree lens and built-in microphone. Has built-in IR transmitters for seeing in total darkness. $199 for camera, 20m cable, AC adapter and stands. Other packages include monitors and two-camera switcher for $299 total. Extra cable is $29.90

Modular cameras -- you choose the entire configuration from the CCD device to the video output format. Known for their large selection of high speed, high sensitivity and high resolution CCD chips (up to 25 million pixels on a single chip CCD).

Offers digitial cameras and acquisition cards in an integrated system for use with PC's. The EDC-1000C is a complete image acquisition system with a 751x488v resolution camera that supports 24 bit color for $950 (including the PC interface card). The EDC-1000HR is the monochrome version. A recently released system (11/94) offers a ADSP2101 DSP on board the acquisition card.

Micro-sized cameras including a 12mm color unit, the UN411E. The ME441E is a remote head B&W ccd camera for machine vision applications. 17mm, 14g. Wide variety of features including electronics shuttering, field/frame modes, interlace and non-interlace etc.

Ultra Minature Camera $149.50. 1.6" X 1.8" X 1" with a 3.6 mm wide angle lens a 1/3 CCD sensor 380 lines of resolution and electronic sutter time of 1/60 - 1/50,000 sec. 12 VDC Video Camera and monitor combination 9" solid state monitor. This is a closed circuit camera monitor system that runs on 115 VAC. There is also a microphone in the Camera. $125.00

Offers a linup of general purpose single CCD cameras. The C4200 is a 768x493V single CCD color camera. The C3967 is a 3 CCD remote head color camera with 786x493V resolution. They also offer off-the-shelf image improvement/enhancing hardware and CCD chips (1024x1024V)

World's smallest low-cost digital camera on a single chip; under $10 for volume users. It is the first commercially available image sensor to have a built-in A/D converter. The Digital Video Camera Chip, VVL1070 delivers a digitized B&W image through processor-compatible serial and parallel ports. The IC uses a proprietary CMOS sensor technology developed by VLSI Vision Ltd., which also is developing a whole series of single-chip EIA cameras that will be shortly introduced to the American market.

The chip features a 160 x 160 pixel array. Pixel size is 10.5 x 10.5 microns. All circuitry to drive and sense the array is packaged in a single Optical Quad Flatpak. The digital converter provides an 8-bit digital output for serial or parallel interface. Other features include an analog output with sync pulses, wide-range electronic exposure control for use with a variety of low-cost fixed-aperture lenses and automatic black level circuitry. Power consumption is less than 100mw.

An Engineering Level Evaluation Kit is available to reduce development costs and allow designers to rapidly develop a prototype using their own defined interface circuitry. The kit includes a fully operational PCB using an LCC with glass lid mounted in an anodized aluminum enclosure with both a "C" mount 12mm lens and a wide-angle 4.3mm fixed-focus lens.

Also offers both a 330 line and 510x492v resolution miniature color cameras.

Mini B/W camera $179.00 2.5x2.5x5cm and 70g. 7-14 VCD and 80 milliamps Also carry underwater cameras, and transmitter/recievers for video.

Offers many types of general purpose monochrome cameras as well as a 811x508V resolution color camera with a variety of output formats (RGB, NTSC, Y/C). The TI-324A is a small high-res B/W CCD camera designed for machine vision and robotics applications. A variety of other B/W and Color CCD cameras are also made.

Sells a complete line of monochrome cameras and a high performance broadcast quality 3 CCD RGB color camera.

Offers gereral purpose, reasonably priced CCD cameras. The TMC-7RGB is a 768x494V resolution color camera with electronic shutter for $1100. Many monochrome cameras are available including a high resolution 1024x1024V. The 'Card-Cam' line of cameras are small PC board cameras with simple C-mount remote heads.

CCD Micro Camera From Chinon. $159.00 B/W 1/3" CCD with a full 250,000+ pixels. 350 lines of resolution. Auto gain control and electronic shutter. 9 VDC at 80 milliamps. Adjustable focus 4mm, f 1.8 lens (provides 78 degree FOV, 10mm to infinity). Standard Composite video out. Weighs 14g, IR Sensitive. Also reportedly sold by by Creative Micro Electronics in Colorado. tel: 303.770.8928, fax: 303.796.0979

Sony XC/999/999P is a nice small color CCD camera the size of a microphone. CCD resolution is 768Hx493V. The 999 is NTSC and the 999P is the PAL format. XC-75 has small camera head and separate electronics. The XC711 is a nice general purpose single CCD color camera with 768x493V resolution, but not as expensive as to XC999. The XC-711 RR is the remote head version. An appreciable lineup of monochrome cameras are offered as well.

Electronic timers and beepers, miniature cameras and transmitters. Super Circuits specializes in affordable microvideo products. One of the tiny cameras, the PC-9XS is about the size of a silver dollar, has 380 lines resolution, 1 lux rating at a price of only $149. Some of the cameras go down to .2 lux. Other products include small color cameras, ATV UHF transmitter kits, Short range transmitter sets, and other specialty video products.

TI makes a full line of cameras and CCD chips includeing linear and 2D arrays. TI makes a $35 CCD Imager, the TC-211, with 192x165 resolution. Newark Electronics sells the TC211-M for around US$50.00 See TI's Array Image Sensor Products data manual for more details. Update: Unfortunately, Telescope Making Magazine went out of business with the issue mentioned above and may be hard to find. Hope to find copy and contact author wrt to posting it.

Toshiba IK-M40A high resolution microminiature color camera. Camera head is 39mm long, 17mm diameter and weighs 16g. 1/2" CCD w/ 410,000 pixels, high sensitivity (5 lux at F1.6) and electronic shutter. RGB output standard. uses cables up to 30m. Several lenses available. About $2K.

Toshiba also makes a very small C-mount Lens color CCD camera, the IK-C40A. It is only slight larger than a 30mm cube.

Wintriss makes a 2048 pixel line scan camera that can be used for object imaging, velocity measurement and positioning with multiple cameras. Can be used to determine spped and trajectory of objects in flight. This has been used in archery applications. RS485 interface with 8Mb/sec serial data rate. Can be linked directly with Wintriss DSP boards for post-processing and communications. Price $1250.

Specializing in High-res CCD cameras. Product line includes a 12-bit 1317x1035 pixel resolution. Target market has been medical imaging. Full computer control and compatible with a number of image capture and display boards.

Much of the initial research, development and marketing in this area were for military applications. However, markets and commercial units are now found in mass market and even consumer applications these days. This has brought the price of systems down significantly. There are several inexpensive gyros used in radio controlled helicopters. These are rate gyros, used to sense the rate of turn about a particular axis (usually vertical, for tail rotor control), and are designed to connect between an R/C receiver and a servo.

These gyros work by modifying the PWM signal that the rx produces, before it gets to the servo. The sensing is usually done by a linear hall effect device, which senses the position of a magnet on the bottom of the flywheel assembly. The gyros have both sensitivity and gain controls, and some can be switched on and off remotely. They have been used for sensing rotation about an axis for a VR headset, with some success. The big advantage is they are relatively cheap, the big disadvantage is high drift rate.

     Analog Devices ADXL50 accelerometer.

Power Supply........................... +5V (+/- 5%)
Measurement Range...................... +/- 50g
Pre-Amp Zero-g output level............ +1.8V
Pre-Amp output span.................... +1.8V (+/-1.2V) at +/-50g
Uncommitted amp output range........... +0.25V to +4.75V
Overall Accuracy....................... 5% of Full Scale
Linearity.............................. 0.5% of Full Scale
Bandwidth.............................. DC to 1kHz
Voltage Noise (p-p)
    at BW = 0.3kHz..................... +/-0.24% of Full Scale
    at BW = 1.0kHz..................... +/-0.48% of Full Scale
Transverse Sensitivity................. 2%
Unpowered Shock Survival............... 2000g

Fiber-optic gyro. 77mm diameter by 88mm high. Analog out porportional to rotation rate. Also digital version available. Rate +/- 100 degrees/sec. Stable over -40C to +85C. Power 8-13.5VDC at 250mA. Bias drift 0.005 deg/sec (18 deg/hr). 0.63kg $1100.00 for digital version, $950 for analog.

Piezo Film Accelerometer Sensors

AHC-04-08 accelerometer/shock sensor contains three sensing elements oriented to measure acceleration in two linear axes and one angular axis. Each sensor has a dedicated channel with adjustable gain, an adjustable comparator, and selectable output control to provide either a digital or analog signal. It is a low profile surface mount chip with 14 pins. It has internal eeprom for programming the adjustable gains, and output modes.

Lower limit on the frequency response is typically about 7-13 Hz. This means if it were subjected to a steady 10 G acceleration for example, the output would rise to 10 G's then decay down to zero even though it were still at 10 G's. This is good for measuring shocks but not steady accelerations. About $30 for a single unit.

GyroChip - a very small solid state angular rate sensor. Based a quartz tuning fork device - all support electronics are included. Max range available: +/-10 deg/sec to +/-1000 deg/sec. Input +/- 5VDC Output scale +/- 2.5VDC. Systron Donner also makes a variety of linear accelerometers and inertial measurement products.

Solid state six axis inertial sensor. It provides analog signals for 3 axis acceleration and 3 axis rate. The package is 7.5cmx7.5cmx8cm, weighs ~600grams and takes +-15V unreg in (7W). Bias drift is on the order of 0.005 deg/sec short term (0.1deg/sec long term).

Cost is $12,000 for one or $10,000 for 2-9 (a good single axis rate gyro usually costs $6K+). Various acceleration and rate range combinations are available (up to +- 20g). Delivery is about 6wks. A new Gyrochip two is available as well. Specs aren't quite as good but it is cheaper.

Variable Capacitance and Piezoresistive Accelerometers. Many models, contact Endevco for literature.

Sells small vertical and directional gyros for ~$500. These are standard gimballed gyros, but the drift specs probaly aren't as good as aircraft-quality gyros. Now also sell innovative computer pointers and devices termed 'Gyroengines' that provide quadrature outputs from heading devices. Gyroengines are $3.5K

Honeywll manufactures the modular azimuth and postioning system (MAPS) and utilizes ring-laser gyros. (RLG). The RLG uses two beams of laser light rotating in opposite directions along a path within a sealed and enclosed cavity. As the unit changes heading, the distances the beams travel differ. This difference is can be measured and is directly related to heading. When combined with linear accelerometers the unit provides position and orientation. MAPS has an RS-422 interface, is approx 22x27x38cm and is 20kg. 100W power draw. [Rad hard and rated for howitzer gunfire!]

Wide variety of gyros, north seekers, vertical indicators, position transducers, pendulums, magnetometers, dynamic stabilization systems, and accelerometer devices.

Model 3145. Signal Conditioned Temperature Compensated 0.5 to 4.5 Vdc Output. 2g, 5g, 10g, 20g, 50g, 100g, 200g ranges. $230 for 1.

Model 3140: Instrumentation grade Signal Conditioned Temperature Compensated 0.5 to 4.5 Vdc Output. 2g, 5g, 10g, 20g, 50g, 100g, 200g ranges. $295 for 1.

Model 3031: OEM Accelerometer Piezoresistive low cost Surface mount package. 2g, 5g, 10g, 20g, 50g, 100g, 200g, 500g ranges. $74 for 1.

Model 3021 and 3026: OEM Accelerometer Piezoresistive low cost. 2g, 5g, 10g, 20g, 50g, 100g, 200g, 500g ranges. Price ranges from $98-141 for 1, depending on g range.

also in Europe:

Nice small well-designed units that provide heading data. About $1K w/ RS232 adapter.

Schaevitz Sensors, a division of Lucas, makes a variety of inclinometers and accelerometers. the S05E is a compact, lightweight, solid state accelerometer. NEMA 4 housing. DC -1KHz freq response, +/-5vdc output, vibration to 20grms, less than 500mW power.

Other linear servo inclinometers and accelerometers: acceleration ranges: +/-0.5g to +/-20g, inclinometer ranges +/-1 deg to +/- 90 deg. Operating temperatures -55C to 95C.

Lucas makes a 2.5cmx2.5cmx1cm (approx) accelerometer for about $200. Good noise immunity but fragile.

Gyrostar piezoelectric vibrating gyroscope. Uses equilateral triangular prism with PE elements attached to faces of prism. High precision compared to other vibration gyroscopes. Measures augular velocity with good linearity. Max augular vel +/- 90 deg/sec, No hysteresis, 58x25x25mm, 45g, output is DC voltage porportional to angular rate. 22.2mV/deg/sec scale factor.

Gerhard Weiss has provided some results of experiments with the unit at [131.246.192.2]: Gyrostar.ps.Z

Two-axis Inclinometer. Weight: 2.3gr, voltage: 5V, current: 20mA, dimension: 12 x 12 x 7 mm, Output: 2 analog output. Sine and cosine for 360 degree, voltage swing: +/- 0.4V, Price: about $100. Rumored to have a US distributor: Dinsmore.

Dinsmore Instrument Company

Precision's Vector-2X electronic compass module is about $50 and provides 2 deg accuracy, 1 deg resolution, 10Hz smapling, serial ouput. Another product the Wayfinder is targeted for VR tracking applications.

Capacitive Accelerometers

Model 1010, Digital output:
Produces Digital pulse train in which the density of pulses (number of pulses a second) is proprtional to applied acceleration. It operates with a single +5 volt power supply and requires a clock of 100kHz - 1MHz. The output is ratiometric to the clock frequency and independent of the power supply voltage. Two forms of digital signals are provided for direct interfacing to a microprocessor or counter. This devices comes in a PLCC package that is smaller than a penny.

Model 1210, Analog output:
Provides two analog outputs, 1-4 volts, or 4-1 volt, with O g's at 2.5 volts. The outputs can be used either differentially or single ended referenced to 2.5 volts. Two reference voltages, +5.0 and +2.5 volts (nominal), are required; the output scale factor is ratiometric to the +5 volt reference voltage.

Model 7170 series and 7130 series capacitive accelerometers. These are relatively large devices with built in ASIC signal processing.They have very good accuracy specs and are pre-calibrated. They also make pressure sensors.

Three-axis accelerometer. A tiny cube just under 2.5cm on a side. Approx $1K

Lists a solid state gyro for model helicopters. The SSG/1 is 38mm x 38mm x 13mm and weighs 43g. Completely solid state with no motor or moving parts. Claims to draw 10% of the power of a gyro with moving parts. No drift specs.

The smallest, cheapest model is 5x5x2 cm and about $250. It has a 5-terminal electrolytic cell that can measure tilt in two axes to +-20 degrees (optional +-45 degrees). The characteristic "slosh" frequency is about 10 Hz, and it exhibits sub-second settling times and a resolution of 0.01 degrees. The output is two analog signals (X and Y, or Roll and Pitch, if you prefer). It runs off of a 9-volt battery.

1. Pulse Timing
2. Phase Comparison
3. Doppler Methods
4. Interferometry

Pulse timing, as the name suggests, involves measuring the round time for a signal to be transmitted to a reflective surface and return.

This is the principle used in Radar, DME for aircraft, LORAN, Satellite Altimetry, Airborne RADAR Altimetry, Lunar Laser Ranging etc. Some of the newer EDM instruments used by surveyor are also using pulse timing and accuracies of +/- 5mm are possible. Most of the military range finders also use pulse timing. The GPS system uses pulse timing for coarse distance measurement. Very Long Base Interferometry (VLBI) is also a pulse timing technique where signals >from pulsars are timed from two or more radio telescopes and the difference in times of arrival are converted to intercontinental distances with a precision of a few centimetres.

Phase difference involves the use of a carrier wave which may be modulated at different wavelengths. By measuring the difference in phase between the transmitted signal and the received signal after it has been reflected from the other end of the target, the distance can be determined as an integer number (unknown) of wavelengths plus a fraction of a wavelength which is known from the phase comparison. By using a range of modulation frequencies the ambiguity can be resolved. There are many applications of this technique. A wide range of carrier frequencies are used ranging from visible through infra red to microwave and right down to VLF. Typical instruments used by surveyors have accuracies of +/-(1to2 mm +1to3 parts per million) and use infra red as the carrier. Precise positioning using GPS can be achieved by phase comparison of the carrier wave signals of the various satellites. Accuracies in position of better than 1 part per million can be achieved.

Doppler techniques were used in the earlier satellite positioning systems. The received frequency of a low orbit satellite is compared with the actual transmitted signal as a function of time. The rate of change of frequency gives the slant range between the satellite and the observer while the instant when the two freqencies are the same gives the point of closest approach. By knowing the orbital parameters of the satellite which are transmitted, the observers position can be determined.

Interferometric methods are the same as those used in the original Michelson Interferometer. It is used for metrology, high precision distance measurement over short distances (up to 60 metres) and in the definition of the metre.

There are a variety of laser rangefinding devices that have been built and used over the past decade for robotics use. The 3D devices are still large, power hungry and heavy but give very nice images suitable for fast map building and navigation work. Expect to pay over $50K for these time-of-flight devices. Most AM Lidars measure phase shift between outgoing and reflected beams. A mirror system rasters the beam forming a video-camera-like image. Some devices supply the reflectance image as well as range which is nice for corresponding the two. Comprehensive references include:

• Electronic Distance Measurement by JM Rueger, Springer-Verlag
• P. Besl, ``Active, Optical Range Imaging Sensors'', Machine Vision and Applications, v. 1, p. 127-152, 1988.
  A longer version of Besl's paper appears in ``Advances in Machine Vision: Architectures and Applications'', J. Sanz (ed.), Springer-Verlag, 1988.

  Other good surveys are Ray Jarvis' article in IEEE TPAMI v5n2 and Nitzan's article in IEEE PAMI v10n2.

• Experimental Characterization of the Perceptron Laser Rangefinder, In So Kweon, Regis Hoffman, and Eric Krotkov. Carnegie Mellon University Technical Report, CMU-RI-TR-91-1. 1991.
• M. Hebert and E. Krotkov. 3-D Measurements from Imaging Laser Radars: How Good Are They? Int. Journal of Image and Vision Computing, 10(3):170-178, April 1992
• International Journal of Robotics Research, Vol. 13, No. 4, Aug. 1994, pp 305-314. {get title}

The AccuRange 400 is an optical distance measurement sensor with a range of 0 to 16m for most diffuse reflective surfaces. It operates by emitting a collimated laser beam that is reflected from the target surface and collected by the sensor. 0.5mm short-term repeatability, RS-232 output and optional 4-20mA current loop. Also PW and analog indication of range available. Visible or IR output available. (670nm and 780nm respectively) Around $2500. 5VDC@300mA. 50KHz sampling rate.

Laser Eye ranging system. It consists of a robotic head with a combined vision / range sensor. The sensor provides colour images and distance to an object in the centre of the camera field of view. There is of course software to process images from the camera and detect a target, to control the head, communication, nice GUIs, etc. Is being used for vehicle navigation.

From the head position you get the bearing to the target and the rangefinder provides you with the distance. Angular resolution is better than 0.05 degree, the distance can be measured up to 100m with accuracy of ~5 cm. Note that the range measurement is 1D along the camera axis.

The cost of the vision system and complexity of the software depends on your specific application: how difficult is it to detect and track your vehicle, how fast is it moving, is it possible to use special markers, is illumination constant, etc.

BCT in Germany makes laser-3D-scanners with a CAD-interface

ERIM has built a number of custom AM laser rangefinders including those used in the ALV (Autonomous Land Vehicle) program. CMU and Martin Marietta have both used this systems in extensive work. Basic system was a 128x64 2fps 20m (ambiguity interval) system.

in US:

$15K LED based IR ranging system. 15cm diameter rotating scanning device with collimated LED light beam that uses phase differences to calculate distance. Range 0.6 to 6m. 2.5cm resolution, 15cm accuracy. 1Khz update rate

Hamamatsu S4282 Light Modulation Photo IC The size of a normal transistor (approx 1/4" square). It has 4 leads, Vcc, Gnd, Vout, LED. All you do is attach an IR LED to the LED lead to give you an instant IR proximity detector (the photo diode detector is built into the part). Two can be aimed at each other and they won't interfere since they'll be out of phase. They have another model with a lens over the photo diode that is claimed could be used up to 30 feet! Hammamatsu also sells a number of photo sensors like color sensors, position sensitive detectors, pyroelectric sensors.

• S4282-11 short range $7.75 single unit
• S4282-72 long range $19.00 single unit

Hyscan laser digitizing systems. High speed 3D surface mapping. Hyscan probe retrofits to any CMM, CNC, or any other translation device. 10,000 points/sec.

     
                 Model 25     Model 50
Accuracy         +/-0.025mm   +/-0.050mm
Resolution (Z)   0.003mm      0.003mm
Depth of field   40mm         80mm
Scan width       70mm         80mm
Stand-off        100mm        100mm
Size                260x110x65mm
Weight                  2.2kg

2D and 3D laser scanners. 8frame/sec, 220 degree view, 4600 points/sec. Accuracy +/- 20mm (1 sigma) from 0.5 - 500? 24W power. System specs can be configured for variety of applications

Manufactures semiconductor laser diode packages and cylindrical lenses. Packages and small and rugged.

Odetics has made a number of smaller laser scanners. That is, smaller than their larger ERIM and Perceptron brethren. I have not heard any independent reviews of the product however.

The Dynasight sensor is a 3-D optical radar that provides real-time 3-D measurements of passive targets with sub-millimeter resolution. Automatic search and track is provided, eye-safe operation and no adjustments or alignment required. Original application was head tracking of computer users but end- effector tracking is also viable. Operatin range depends on target size 0.1-1.5m for 7mm target, 0.3-4m for 25mm target and 1 to 6m for 75mm targets. RS-232 interface. Accuracies 1mm cross range and 4mm down range, resolutions 0.1mm cross range and 0.4mm down range.

A number of labs have built light stripe devices using projected light LCD shutters and laser line projectors determine distance through geometry (as opposed to directly measuring distance through time-of-flight means) One common need is that of generating the laser line.

A spin-off of ERIM, Perceptron has also built a number of AM laser rangefinders. CMU and Caterpillar have used these for map building and obstacle avoidance work in rough terrain navigation.

LASAR product - provides range and reflectance. Programmable field of view (15 to 60 deg) Vertical viewing angle from 3 to 72 degrees. Depth of field from 2 to 40 meters. Up to 1024 x 2048 pixels per image (programmable) and 360,000 pixels/second data acquisition. VME and PC-compatible interface cards available. Windows software provides starting point for custom applications. Less than $50K with a variety of performance and interface options.

[company HQ is Dr. Johannes Riegl GmbH, 85 km, NW of Vienna, Austria]

Laser range finders, laser speed sensors, laser distance meters, motor scanners, laser radar systems. Pulsed laser devices. One of the neatest is the Laser Scout, which gives range, azimuth and inclination to the target and can be used with GPS to give position coordinates of the device you are pointing at. $10K. Accuracy up to +/- 10cm (depending on model)

Laser Radar Scanner (LRS 90-3) is a 1D scanner with 36 deg field of view and a +/- 3cm accuracy. 2-80m distance, $10K. There are several other distance models as well.

Schwarz makes some very nice point range laser ranging devices. These devices are slightly bigger than a soda can. About $6-12K. CMU experience for use in simulated unmanned air vehicle platform worked well. Their MARS (marine angle range system) is a rotating laser device that reflects off targets in the environment. Max range up to 1000meters using corner prisms. Accuracy +/- 1m. Erebus (Dante) Scanner used Schwarz device as base.

Rich Voyles embarked on a force/torque sensor comparison many months ago and compiled some of the results in a paper that is available via the web or anonymous ftp.

http://www.cs.cmu.edu:8001/afs/cs.cmu.edu/user/deadslug/ftp/home.html ftp://ftp.cs.cmu.edu/usr/anon/user/deadslug/ft.sensor.ps.Z The paper is woefully incomplete. The JR3 sensor we borrowed was broken so we borrowed another and got limited data. The old Lord data collection is incomplete and the Assurance Technologies data is not fully included in the report. There is some data from California Cybernetics. If there is sufficient interest, we can finish the compilation. By the way, we only seek to provide the data we gathered an make no claims as to its accuracy or completeness. Use at your own risk. The opinions expressed do not represent those of Carnegie Mellon University nor any of its sponsors. Send e-mail to robodude@cmu.edu with the subject "More Force Data" if you read the report and would like to see it expanded. Any other comments can be put in the body. -Richard Voyles

Analog Devices have the ADXL50 accelerometer which comes in a 10-pin TO-5 can. It is primarily used with air-bags and has a 1994 projected price of $5 in quantities. In the Electronic Design August 8, 1991 issue it quoted the current price as $21.75 for 1000 off quantities. Analog Devices ADXL50 accelerometer.

  Power Supply........................... +5V (+/- 5%)
  Measurement Range...................... +/- 50g
  Pre-Amp Zero-g output level............ +1.8V
  Pre-Amp output span.................... +1.8V (+/-1.2V) at +/-50g
  Uncommitted amp output range........... +0.25V to +4.75V
  Overall Accuracy....................... 5% of Full Scale
  Linearity.............................. 0.5% of Full Scale
  Bandwidth.............................. DC to 1kHz
  Voltage Noise (p-p)
    at BW = 0.3kHz..................... +/-0.24% of Full Scale
    at BW = 1.0kHz..................... +/-0.48% of Full Scale
  Transverse Sensitivity................. 2%
  Unpowered Shock Survival............... 2000g

Largest supplier of multi-axis force sensors. Use silicon rather than foil strain gages for lower strain levels and increased life. F/T sensor ratings from +/- 15lbs to +/- 150lbs (+/- 15 in-lbs to +/- 600 in-lbs) weights are 0.4 and 2.2 lbs for the 4 available sensors. Serial or parallel digital interface or analog interface. ATI also makes robotic tool-changers and an RCC device for assembly operations. An ATI sensor is also incorporated in the Hughes SMARTee end-effector.

Array sensor system that uses PVDF ultrasonic emmitter/detector attached to an elastomer material. Time-of-flight of the pulse as it bounces off of other side of the material is porportional to distance through the elastomer. The distance is porportional the pressure on the pad. Bonneville claims it can be made thin enough for a skin and they have pictures of it being used on a robot finger picking up a washer which can be recognized on their output graphics. Example product:

Model 300 - 16x16 tactile sensor system - $5K

TOF resolution - 12.5 ns

Sheet thickness resolution - 6 microns

Pressure resolution - 0.5 psi (3.4 kPa)

Force resolution - 1g

Rubber linearity - 5-15% deviation

Overload - > 1000PSI (7000kPa)

Spatial resolution - 1.8mm

Scan rate on 16x16 pad - 240 Hz

Six DOF F-T devices. Up to 1000Hz sampling rate, reportedly easy to interface.

PER-force - A 6dof compact force-reflecting controller. Can be used for teleoperationor interactive graphics applications.

Conductive rubber and conductive inks. You build a semi-rigid circuit board with inter-digitated fingers to apply to one side of the rubber. The rubber has a rough surface that under increasing load allows more rubber to contact. They can make rubber with all sorts of conductive properties.

Uniforce Force Sensors. They function similiar to a variable resistor in an electrical circuit. As a force is exerted on the sensor, the two layers of pressure sensitive material compress together and cause a change in resistance which corresponds to a change in pressure. As force increases, resistance decreases. A Uniforce experimenters kit is available for $550 and includes PC-AT card, cables, software, manual and nine Uniforce sensors in three force ranges. They have ISA boards, PCMCIA version and a PPIO version as well. Sensors available in ranges from 0-500g to 0-400kg. Uniforce sensors can be provided in a wide variety of shapes, sizes and force ranges. Software is also available to display force values in real-time.

A 6-dof end-effector with automatic load sensing and compensation. Control modes include position control (cartesian with user spec-ed poses and frames), impedence and force control modes. Programmable behaviors (sliding, hinge, move-to-touch, guarded move, follow etc), open architecture (VxWorks, VME, user-linakable libraries) and a lot more. Interfaces available included RS-232, ethernet, RS-422 and SCSI. Pretty amazing end-effector!

Force Sensing resistors made from polymer thick films. Very thin. Response is approx. 1/R to force. Article in March 1993 issue of Electronics Now/Radio Electronics.

6-DOF force-torque sensors. Strain gage technology. Newer packages have all electronics built into the sensor. Make some high-force devices as well. CMU's Ambler used JR3's on all the feet with good success. Complete force torque data at 8Khz, signal digitization within sensor body, low noise susceptibility, synch serial at 2MHz, inexpensive cabling.

Sensor Skin for Robots. The Skin is designed to assist robots working in constrained, hazardous, dynamic, or high cost environments. The system uses a whole-arm proximity sensing systems for articulated robots that provides complete voverage of the entire manipulator to ensure that every obstacle in the robots path can be detected and avoided. The proximity sensing technology is based on IR arrays which they call "SensorCells". It allows the use of IR, acoustic and capacitive (under-development) sensors in the same sensor skin. The two main components of the Skin are smart sensor modules and the flexible printed circuit board skin. Module sockets are placed at regular intervals on the flexible skin and simply plugged in by the user where required. Redundant cables carrying data and power are connected to each panel. But a minimum of four cables can be used for up to 1024 sensors.

Silicon Designs makes capacitive accelerometers.

Model 1010, Digital output:

Produces Digital pulse train in which the density of pulses (number of pulses a second) is proprtional to applied acceleration. It operates with a single +5 volt power supply and requires a clock of 100kHz - 1MHz. The output is ratiometric to the clock frequency and independent of the power supply voltage. Two forms of digital signals are provided for direct interfacing to a microprocessor or counter. This devices comes in a PLCC package that is smaller than a penny.

Model 1210, Analog output:

Provides two analog outputs, 1-4 volts, or 4-1 volt, with O g's at 2.5 volts. The outputs can be used either differentially or single ended referenced to 2.5 volts. Two reference voltages--+5.0 and +2.5 volts (nominal)-- are required; the output scale factor is ratiometric to the +5 volt reference voltage.

Prices start at about $100 and they offer a digital accelerometer evaluation board for $200.

Model 7170 series and 7130 series capacitive accelerometers. These are relatively large devices with built in ASIC signal processing. They have very good accuracy specs and are pre-calibrated. They also make pressure sensors.

Bend sensor for glove device. Their business is custom membrane controls: switches, membrane potentiometers, and the bend sensors.

Acoustic time-of-flight devices have been around for awhile now. The ubiquitous Polaroid device is cheap and easily integrated and has has found wide use in robotic devices. Other companies have developed nice complete turnkey sonar devices though and Polaroid is no longer the only choice.

Polaroid Ultrasonic Components Group offers two ultrasonic ranging kits:

Specs:

Distance range: 0.26 to 10.7 meters

Resolution: Nominal +- 3mm to 3m, +-1% over entire range

Sonar acceptance angle: approx. 20 degrees

Power Requirement: 6VDC, 2.5 Amps (1 ms pulse), 150mA quiescent

Weight: Transducer, 8.2gm, Ranging module, 18.4 gm

Designer's Kit:

1 transducer, 1 ranging module, electronics display accurate to 1/10th meter. Cost is $169

OEM kit:

2 transducers, 2 ranging modules. $99.

Piezotransducer kit

2.5cm-1500cm +/- 1%, RS-232 port and analog output, extra real estate, $299

Polaroid has several new products as well: K-series piezo transducers and 9000 Series Environmental Transducer.

Modifying the drive circuitry:

The board has two extra signals: BLNK and BINH. Asserting BLNK (driving it HIGH) resets the ECHO RS-latch, and asserting BINH shortens the internal blanking interval (which is 2.38 ms by default). Thus, the solution would seem to lie in asserting BINH after a reasonable amount of time (less than 2.38 ms after asserting INIT) to detect objects closer than 1.3 feet. This doesn't work very well because BINH is very susceptable to noise, and attaching a driver to it wreaks havoc possibly because of the anomalous current sink during the transmit phase. This can be fixed by asserting BLNK during the blanking period (ie the new blanking period) while negating BINH and asserting BIHN after the blanking period while negating BLNK. This can be done easily with a one-shot or some other timing device (eg computer timer, etc).

A computer timer can be used. The timer goes HIGH tblank ms after INIT is asserted, where tblank=0.15*dist and dist is the threshold distance in inches). The timer output goes to BINH and the inverted timer output goes to BLNK. The timer output should be inverted with an LS/TTL inverter to delay the negation of BLNK, otherwise the RS latch may do weird things. [From Richard LeGrand]

Nice complete sensor package, 5 degree cone angle

At one point TI made a Type SN28827 Sonar Ranging Module. See TI Applications Notes D2780. Under $50, needs only 5VDC Not sure if these units are still manufactured but they are often in surplus catalogs. However some other products include these: See data sheets at: http://www.ti.com/sc/docs/psheets/SPECIALF.HTM Data sheets available in several formats. 1. TL851, SONAR RANGING CONTROL 2. TL852, SONAR RANGING RECEIVER

P02 pan/tilt head. High speed with digital servos (120 deg/sec), encoders and continuous rotation. Controller as well.

BSS makes a small pan/tilt unit:

4.5" high by 3.5" wide x 3.5" long

40 oz.

12V dc

operating current 150 mA

pan 359 degrees

tilts 160 degrees

Price: $3100

CameraMan is a pan/tilt device built to support any camcorder and has a wireless interface to an external remote control. 360 deg pan and 50 deg of tilt. The unit is made by ParkerVision and sold through Columbia AudioVideo (and probably other suppliers)

Standard CCTV pan-tilt devices like those from Vicon and others. Inexpensive but no computer control. $557 - $1400

Small computer controlled pan-tilt unit Model PTU-46-17.5 Weighs 1kg and can support ~1.5kg camera payload. Very nice specs: 330 deg/sec slew, 3.06 arcmin accuracy, on-the-fly position and speed changes. 11-40VDC unregulated power input, RS-232 interface. Can use RS-485 using RJ-11 to provide control of multiple PT units. Cost: $1935 Includes PT unit, controller, cable and power supply. $1800 w/o power supply.

Efston is the Canadian Distributor for Edmund Scientific

Motorized Pan/Tilt platform with remote control:

   (mounts upon a camera tripod)
   - auto pan mode
   - variable speed
   - 2.75"W x 2.25"L platform with .25-20 mount screw
   - independent +- 15 degree max vertical pan
   - independent +- 90 degree max horizontal pan
   - autopan switch selectable +- 30, +- 60, +-90 degree scans
   - remote control has 20 foot cord
   -           cat # B38,485           US$215.00
   - ac adapter      B38,486           US$33.95
     

MicroPan PTX-400 very small P/T designed for remote viewing with micro-CCD cameras. Weight 115g. Height under 7cm.

Fujinon CPT-10. 300 deg pan, =/- 95deg tilt. 15 deg/sec speed. 2kg. Payload 4kg. Analog input control.

Instead of a conventional camera, you use one with a very wide fish-eye lens. The (very distorted) image is then sent thru a box that digitizes and processes the data in order to simulate a regular camera. You can (completely in software) pan, tilt, rotate, and zoom the image with great flexibility. $10K.

Underwater pan-tilts including Cobra, very small design.

Underwater P/T systems, expensive but very nicely packaged. PT-5 is a new subminature P/T device that can accomodate a small CCD color camera and mini wet&dry lights. The P/T is 13.5cm high and 10cm wide. Uses small brushless motors with harmonic drives. Radiation tolerant and corrosion resistant. 360 scan on both axes.

Underwater Pan/tilt devices.

H-S is an upscale mail-order outfit that's been around since 1848 and has stores in New York City, Beverly Hills and Chicago. They currently show a wireless pan-tilt unit in their catalog. IR remote control, +/- 20 deg tilt and +/-90deg pan. Can be set to do continuous 90 deg panning and can even control power zoom on many camcorder models. Powered by 6V batteries built into Sony, Panasonic and Sanyo-Fisher or JVC camcorders. 8.75cmH x 11cmW x 14.5cmL AND .45kg. Item 63201B in H-S $149.95. The Picture shows the label SUNPAK and AP 200W (model number?) - [If anyone has further information on the manufacturer or other sales outlets let me know - nivek]

Computer controlled P/T devices - fairly large though.

An all-electronic pan/tilt/zoom resampler. That is, they put a box behind a camera with a fish-eye lens. The box has digital inputs for pan, tilt, zoom, rotation. The box resamples the video signal and produces an output as though the image were acquired by a camera with those parameters. Used as an alternative to pan/tilt devices.

Small Pan/tilt head.

In many applications there is a need to accurately measure the position of an end-effector (hand or gripper) or find coordinate locations on objects, or track motion, or give a time and position history of a moving object. Virtual reality applications need this kind of device to provide realtime adjustments to views that are projected to VR users. See sci.virtual-worlds for discussions on this topic. Robotics people have needed this to provide accurate assessments of manipulator motions and mobile robot positions.

An excellent paper on the subject of sensing and methods of using that information is: "Where Am I? Sensors and Methods for Autonomous Mobile Robot Localization." Technical Report, The University of Michigan UM-MEAM-94-21, December 1994." It is a comprehensive survey on Mobile Robot Positioning. This survey is over 200 pages long, has 130 illustrations and nearly 300 references, and took well over one man-year to complete. The survey is entitled "Where Am I? Sensors and Methods for Autonomous Mobile Robot Localization" A description and table of contents can be found here. To download the report go here and read this file first. Alternatively, you can look at a detailed Table of Contents from within Johann Borenstein's WWW Homepage at: Johann's Home Page Before you download the actual survey, you should read the "readme.txt" file for compatibility tips, and you should read the "um_index.wp5" file to see if you want to download all or only selected chapters of the report. The Global Positioning System (GPS) is an excellent positioning system that is useful in outdoor settings, although recent developments in Psuedolites (Pseudo Satellities) may bring GPS technology indoors and to urban envrionments. While accuracy is intentionally degraded by the US Military recent advances in differential systems and innovative tracking techniques can give 20cm real-time accuracy. Even newer techniques such as carrier-phase are bringing this figure into the mm range for real-time. See news:sci.geo.satellite-nav for full discussions of this technology.

Papers: Useful papers to solve for transforms from positioning devices for multiple reference frames:

• Roger Tsai and Rainer Lenz, IEEE Trans. on Robotics and Automation, Jun 1989.
• C. C. Wang, IEEE Transactions on Robotics and Automation, April 1992. Useful papers for evaluating 3 ad 6 DOF human input devices:
• Shumin Zhai, Investigation of Feel for 6 DOF Inputs: Isometric and Elastic Rate Control for Manipulation in 3D Environments, Proc. Human Factors and Ergonomics Society 37th Annual Meeting,Seattle, WA, October 1993.
• Shumin Zhai and Paul Milgram, Human Performance Evalulation of Manipulation Schemes in Virtual Environments", Proc. Virtual Reality Annual International Symposium, IEEE, Seattle, WA, September 1993.
• Shumin Zhai and Paul Milgram, Human Performance Evalulation of Isometric and Elastic Rate Controllers in a 6 DOF Tracking Task, Proc. SPIE vol. 2057, Telemanipulator Technology", Boston, MA, September 1993.

Blevins writes their own utilities and sell 3D digitizers starting @ around $2,400 on up to around $75,000. Software is compatible with Lightwave and 3D Studio modelling programs and will be ported to SGI and PC's soon. Provide software to talk with Polhemus, a sonic digitizer and a jointed-arm unit from Immersion.

Has 3D scanner. Cyberware has software for editing 3D models, and stitching multiple scans into a single coherent whole. Software is $5-10K each. Cyberware 3030RGB/HIREZ scanner with MM motion platform, complete with all software, training and one-year support costs [US] $75,200.

In the US

Eshed's V-scope allows you to measure, record, process, and demonstrate the motion of one or more bodies in one, two or three dimensions. The V-scopeTM system uses tracking technology which emits infrared signals to trigger ultrasonic response signals. This technology allows full three-dimensional tracking within a space of a few meters, with resolution of a fraction of a millimeter. See V-scope for more details.

Intelligent Solutions Inc. was formed in Nov. of 1993 by four of the former engineers of Denning Mobile Robotics. They are focusing on building smart sensors and their first product is the EZNav Position Sensor. EZNav is a precision optical position sensor that can be used on moving platforms such as automated guided vehicles, robots, or material handling equipment. EZNav uses an eye safe scanning laser with a 360 degree field of view to measure the azimuth angle to wall mounted reference reflectors. This angle data can be used to triangulate the position and heading relative to the known target locations. EZNav is unique in its ability to use passive reflectors as well as coded electronic targets. Current work includes adding the triangulation calculations to the EZNav sensor and a new Ultrasonic based position sensor.

Specs:

Target Range 30m passive up to 180m active

Abs. Accuracy +/- 0.03 degrees RMS

Scan Rate 12 per second

Data Rate 9.6k baud RS 232

Power 24 volts at 300 ma

Size 30cm Dia x 35cm High

Weight 4.5kg

Eagle Eye (TM) is a Power Macintosh application that accurately tracks specially designed passive optical targets. It can track multiple targets simultaneously in visually cluttered environments using a single video camera. For each target that it can see, it is able to determine seven parameters:

• the target's identity (via the information encoded on the marker);
• the target's position (X, Y, and Z with respect to the camera);
• the target's orientation (roll, pitch, and yaw with respect to the camera).

Systems can operate up to 16m distance and with a localization accuracy under 20mm in static and 70mm in dynamic localization. DLPA was developed in cooperation with Laboratorium, DIST - University of Genoa. email: sand@dist.unige.it, vercelli@dist.unige.it and URL website

3Space, Isotrak, FasTrak: Electromagnetic devices for sensing xyz and rotations remotely. Limited to 1m or so radius. Sensitive to metallic objects in vicinity. Approx $3k

Sales: Jack Scully Technical Support: Steven Work Product is called Flock of Birds. A 6d0f measuring device. Ftp site is ftp://ftp.std.com/ftp/vendors/Ascension/

gen_lit.txt

Contains general literature on 6D motion tracking system. Accuracy Specifications, comments from prominent users, list of 3rd party software vendors, FAQ on tracking system, etc. Ascii text.

tecpaper.wp6

Technical Description of Flock of Birds (TM) 6D tracking system. In Binary WordPerfect 6.0 format.

userware.zip

Latest version of our User Software, including source code. Enjoy. pkzipped binary file.

manual.wp6

Latest version of our User Manual. In Binary WordPerfect 6.0 format.

readme.txt

more info on files located in Ascension's FTP directory. Ascii text.

The Ascension Flock of Birds tracker is DC pulsed, where the Polhemus is AC magnetic field. The AC field set up standing waves in metal (conduction and ferrous) which magnify the distortion effect.

Charts provided by Acension:

KEY  PERFORMANCE  PARAMETERS OF ASCENSION  &  POLHEMUS  TRACKING  DEVICES

Parameter                         Ascension        Polhemus     Polhemus
                                Flock of Birds     Isotrak II    Fastrak
Measurement Rate
 (Measurements/sec)
        1 Receiver                      144             60        120
        2 Receivers                     144             30         60
        @ Max Number of Rcvrs           144             30         30
Maximum Number of Receivers              30             2          32
Number of Transmitters to                 1             1           4
Support Max Number of Receivers
Maximum Data Output Rate                312K            115K       115K
 (Baud or Bytes)
Lag Increase with Multiple              No              Yes        Yes
Receivers**
Range - Standard Transmitter            3'              5'*        10'*
        - Extended Transmitter          8'              N/A        N/A
Accuracy Degradation Due to:
        Conductive Metals               Low             High       High
        Stainless Steel                 None            High       High
         (300 series)
CRT Interference Rejection              Yes             No         Yes
LCD Noise Susceptability                No              Yes        Yes
Unit Cost (1 Receiver)                  $2,695          $2,875     $5,750

** Note 2: For a complete discussion of latency in competitive motion trackers, contact Ascension.

                                     
Specifications:
 Technical
     Translation range:       plus or minus 3'(8' optional) in any direction
     Angular range:           plus of minuw 180 degrees Azimuth & Roll
                              plus or minus 90 degrees Elevation
     Translation accuracy:    0.1" RMS
     Translation resolution:  0.03"
     Angular accuracy         0.5 degrees RMS 
     Angular resolution       0.1 degrees RMS @ 12"
     Update rate:             Up to 144 measurements/second
     Outputs:                 X,Y,Z positional coordinates and orientation
                              angles or rotation matrix
     Interface:               RS-232C with selectable baud rates to 115,200; or
                              RS-422/485 with selectable baud rates to 310,000
     Format:                  Binary
     Modes:                   Point or stream
 Physical
     Transmitter: 3.75-inch cube (internally mounted in Enclosure or 
                  externally mounted with 10' cable) or extended range 
                  transmitter option: 12-inch cube externally mounte with 
                  20' cable
     Receiver:    1.0" x 1.0" x 0.8" cube (or optional 3-button mouse) 
                  with 10' or 25' cable
     Enclosure:   9.5" x 11.5" x 2.6"
     Power:       User provided or optional external plug-in: US/European 
                  version
     Environment: Large metallic objects in operating volume may degrade 
                  performance 

RSI Research makes a 6 DOF joystick. It has a medium workspace (about 10 cm radius) and several buttons.

ADL-1 6DOF tracker. Gives position/orientation measurements up to 240 times/second, with low latency (0.35 to 1.88 milliseconds.)

Mattel marketed the PowerGlove for use in gaming (Nintendo). It tracked finger motions through small bend sensors. The Mattel PowerGlove was developed by Abrams-Gentile. The sensors themselves are simple resistors varying from about 200K to 500K ohms depending on the amount of flex.

email: Soon. Messages to hpm@cs.cmu.edu will be forwarded. Denning-Branch is a merger of Denning Mobile Robotics, once located in the Boston area, and makers of human-size mobile robots since 1983, and Branch and Associates, of Hobart, Australia, designers and builders of smaller mobile robots since 1979. LaserNav Robot-mounted scanning infrared laser unit that uses wall mounted bar-coded retroreflectors or active transponders to navigate to centimeter precision in 10-meter-scale areas. $8K

GCS's core group developed the rotating scanner and passive target system. Featured in several papers out of Oxford. Uses passive targets with barcodes. Targets have unique ID's and surveyed positions. Rotating laser gives angles between targets. Target positions combined with angles gives vehicle position and heading. 2Hz scan rate but clever use of dead reckoned information and kalman filtering gives very impressive results. New products go to 200-300m ranges.

Innovision specialized in non-contact measurements. 2-3 dimensions. On-site, software development, leasing. They are representatives for several non-contact measurement systems. See Below.

Update speed: 20 hz Position accuracy: +/-0.05inches (1.27 mm) This really depends on range as well. direction accuracy: +/- 0.05 degrees. 3D reference points covering up km distances. 1D, 2D or 3D feedback. Cost: About $6K-$10K for positioning system. Custom software available for graphing, updating etc. Accuracy available even when the robot is moving at several meters/sec.

Selective markets optical triangulation laser-based devices and laser gaging systems. They also make the Selspot tracking system. The Selspot is a two camera system that registers 3D position of IR LED's at very high data rates. Selspots Robot Check System can provide non-contact 3D measurement and analysis of robot motion at 500 Hz rate. System has been used for over 20 years. Used in motion studies for people, animals and robots. Active markers are used (IR LEDs) Fast sampling up to 10K Hz. Selspot is marketed by: Innovision Systems

MacReflex system uses CCD-based cameras for non-contacting measurement of robots. Two camera system is typical. Uses small passive targets and IR LED's colocated with the cameras lens. Video processor calculates centroid of markers and displays in real-time. Information is used to provide data and analysis of position, velocity, acceleration, angles, angle velocity and acceleration and position vs. time. Specs: Noise level 1:200000, resolution 1:70000, Relative accuracy: 1:30000, and absolute accuracy 1:10000. Accuracy is defined as standard deviation of difference between measured and true positions/longest diagonal in measurement volume. 50Hz and 120Hz and high accuracies.

MacReflex is marketed by: Innovision Systems

Coordinate Measuring Machines

Renishaw makes a ballbar mechanism to measure and calibrate machine tool motion errors including backlash, servo error, squareness, straightness, axis reversal, vibration, scale mismatch etc. It uses a precise linear measuring device and interpolates a circular profile from which all the above information is calculated.

Renishaw also makes a high speed digitizing and scanning system for the tool and die industry. It's a CMM style machine that can generate NC programs from scanned parts. They also have a scanning system that retrofits to existing CNC mills. Supraporte Inc

Portable 6-axis measuring system. Model 2000 now available with battery power pack. Very accurate. Very expensive.

Metrecom: 6DOF articulated pointer, like a portable CMM. Endpoint accuracies are around .005" -> .025", depending on model. Counterbalnaced design. Three models from 1.8m to 2.4m reach and accuracies ranging from +/- .635mm to .127mm and prices from $14.4K to $51.4K respectively.

Laser metrology systems. CMS-3000 is a servo controlled tracking laser interferometer measureing tool. The tracker follows a retroreflective target whil providing real-time coordinate information of the retro center location. Position of the target is provided in XYZ coordinates via linear distance and two high accuracy angular encoders. CMS-3000 can provide measurements over a large volume. 30m radial, > 110 degrees elevation, > 270 horizontal. Down to 0.6 micron resolution, 2 parts in 10^5 accuracy for range. (1m/sec tracking) up to 6m/sec tracking at 5 micron resolution. Lightweight and cost effective versus CMM's and offers speed and accuracy advantages over theodolites and photogrammetry equipment. System can be leased by hour/week/month. About $180K to buy.

Balluff

MTS Systems Corporation (Temposonics)

Norstat

The AT1000A is a single chip sensor interface circuit that has been used in pressure, acceleration, temperature and humidity applications. 20 PIN SOIC Package, 12-Bit A/D Converter, 64 Bits EEPROM memory. Programmable pulsed current source via EEPROM memory. Three channel A/D: Iout1,Iout2, and Vdiff.

Types of motors:

• Synchronous
• Stepper
• AC servo
• Brushless DC servo
• Brushed DC servo

What is the wiring for R/C servos?

Pin 1 = White = Signal

Pin 2 = Red = +5

Pin 3 = Black = Signal and Power Ground

[Tang = pin 1]

    ___ ...                                              ___
   |   |  .                                             |   |
 __|   |__._____________________________________________|   |____
    1 to 2 ms width pulse goes from full CCW to full CW rotation
    20 ms pulse to pulse.

How can you reverse a servo?

A harder way is as follows: You have to reverse both the motor and the potentiometer leads.

It would be much easier to reverse the control input. All modern radios have "reverse" switches for all channels. In the past you could have one of 3 solutions:

1. Live with the servo as-is. Design your model with the servo direction in mind.
2. Some companies had "reversed" servos. Probably no longer available.
3. Use a gadget between the receiver and radio that reverses the servo. Possibly a single 4538 (Motorola MC14538) with 2 resistors, 3 capacitors and a trimmer pot.
4. Modify the servo. This is the most difficult and least desired solution. Impossible if the motor is soldered directly to the PCB (seen in some servos). [from Itai Nashon]

The Juggler's Delight: PIC-based Controller For Up To Eight Servos by Scott Edward. The Computer Applications Journal, October 1994 p14 [A kit is available as well for the circuit, including PC board, IC's etc]

How can you control a servo from a parallel port?

With one of the PC's internal timers cranked up, it is possible to control eight servos from a common parallel port with nothing but a simple TSR interrupt service routine and a cable. In fact, power can be pulled from the disk drive power connector and the PC can run all servos directly with no additional hardware. The only down side is that the PC wastes some processing power servicing the interrupt handler.

How can you implement force servoing with RC servos?

I successfully built a force-feedback circuit for my Futaba hobby servos. I took the back off the servo case to expose the solder side of the control PC board, and using my scope with the servo active, I looked for contacts whose signal looked like it varied with how much work the motor was doing. I found 2 pulse-width modulated signals which correspond to the difference between the command signal and the current shaft angle, one for each rotation direction.

The signals are not logic-level, but vary between, say, 1 and 2 volts, so I built a simple comparator circuit to convert these to logic level. I fed these into my 68HC11 and used the Input Compare feature to measure the timing.

To connect to these points, I used some thin stranded wire and soldered directly to the PC board in the servo. Obviously you need to be careful when doing this to avoid damaging the servo. Then I threaded the pair out through the same hole that the control and power wires use.

One thing to keep in mind with this setup is that it measures the error signal, not the force. Therefore when you tell your servo to move to a different angle, you'll get an error signal for a few wavelengths until it is able to turn the shaft to the new position, even if there is no resistance to the movement. If your software can take this into account, it works fairly well.

There's also the problem of saturation - if the external torque on the servo shaft is actually turning the shaft against the motor, the error signal will be saturated, and you won't know how much past saturation you are.

How to implement RC servo control from a Microcontroller like the HC11?

If you want to generate PWM with 20mS, you can set up an interrupt to go off after 20mS, set the output line(s) high, and set the output compare(s) to the current time plus the desired offset. Then set the next interrupt to occur after another 20mS. Still pretty easy.

For code examples, check out the TRP2 and TRP3 files in: ftp://cherupakha.media.mit.edu/pub/incoming/dickens This is the code for 2 articles Tom Dickens wrote in The Robot Practitioner.

Commercial controller for RC servos:

Pontech has a SV100 Servo Motor Controller which is based on the PIC 16C84 microcontroller. It accepts RS232 serial data signal from a host computer and poutput PWM to control up to four RC servo motors. Multiple boards can be parallel together to allow more servos. They also sell FUTABA FP-S148 servos. boards: $49.95, servos: $16.95, + $5.00 shipping and handling Vantec

Design and manufacture of Electronic Systems for remote control mobile robots and vehicles. Vantec makes a servo control that has been used successfully in this type of application and can be used for velocity or position closed loop control. We can also modify R/C transmitters for operation on special frequencies. contact: Rich Howe

At room temperature Muscle Wires are easily stretched by a small force. However, when conducting an electric current, the wire heats and changes to a much harder form that returns to the "unstretched" shape - the wire shortens in length with a usable amount of force.

Nitinol can be stretched by up to eight percent of their length and will recover fully, but only for a few cycles. However when used in the three to five percent range, Muscle Wires can run for millions of cycles with very consistent and reliable performance.

     
            Table 1.  Flexinol Muscle Wire Properties
-----------------------------------------------------------------
               Wire    Linear  Typical  Deform. Recovery  Typical
Wire       Diameter    Resist. Current  Weight*  Weight*   Rate**
Name       (microns)  (ohm/m)     (mA) (grams)   (grams)  (LT/HT)
-----------------------------------------------------------------
 Flexinol 037     37       860       30       4       20    52/68
 Flexinol 050     50       510       50       8       35    46/67
 Flexinol 100    100       150      180      28      150    33/50
 Flexinol 150    150        50      400      62      330    20/30
 Flexinol 250    250        20    1,000     172      930     9/13
-----------------------------------------------------------------
   * Multiply by 0.0098 to get force in Newtons
  ** Cycles per minute, in still air, at 20 Centigrade
     LT = low temp 70 degrees C, HT high temp 90 degrees C

Memry sell a Mitsubishi developed polyurethane based Shape Memory Polymer. The material undergoes property changes in hardness, flexibility, elastic modulus and vapor permeability under temperature change. Medical applications is one focus for this material.

Importers of the Parallax BASIC Stamps and Muscle Wires into the UK.

Sheets and wire of NiTinOL alloys.

[10.2.3] Other Actuators

Rubbertuators: Rubber-based device that bends under applied pneumatic pressure. For a rotation unit typical rotation angles are 360,120,90 degrees for linear unit the contraction rate cannot exceed 20%.

[10.2.6]DC Motors

Mabuchi Motor America Corp.

One of the largest manufacturers of small motors. Found in R/C cars.

There are a wide variety of frame grabbers, computer vision systems and image processing tools available. For VME, Multibus, PC Bus, even SBUS and STD, there are a number of options for getting images into your computer.

DASM-VIP

Input:

RGB, Y/C, NTSC, RS-170A, CCIR, RS-343A

Memory:

up to 16mb

Bus:

SCSI (2.5 Mb/s asynch, or 5 Mb/s synch.) Can be interfaced to PC/ISA via SCSI card.

Processing:

TMS320C31 33.3 MHz, 33.3 MFLOPs, 16.7 MIPS. Analogic also provides an 'ISA bus Floating-Point DSP Signal Processor' AP85c with a SCSI port and 5 TMS320C31 processors for 200 MFLOPs, and up to 16Mb of global DRAM and upt to 1Mb of local SRAM per processor.

Other:

RS-343A, CCIR, NTSC, or S-Video display output. User programmed RS-232 port for debugging, or whatever. An optional multi-tasking realtime DSP operating system written by Analogic is available. DASM-VIP with 16Mb costs $5995. The AP85c with 16Mb is $12,600.

Offers a vision system mostly targeted for industry. Good selection of image processing routines. 5000 Series

Input:

Up to 4 cameras multiplexed, RS-170 or CCIR 12 bit grey scale

Memory: up to 16Mb

Bus:

ISA

Processing:

25Mhz 68030, 68882 Floating point coprocessor, 'VC-1' custom ASIC for 2D correlation, blob analysis, histograms, and various transforms, 'VC-2' custom ASIC for character recognition, line finding, edge detection, Gaussian and LaPlacian filtering.

Other:

Functions as VGA adapter eliminating the need for a separate video card -- allows display of images. Also provides RGB and monochrome video outputs.

A variety of ISA DSP-based bus frame grabbers and imaging cards for PCs. Inputs for many cards includes RGB, NTSC, RS-170, CCIR, or PAL 24 bit color, Y-C, RS-330, up to 16Mb VRAM and 64Mb DRAM. DSP-based boards. Outputs include external display support, composite video etc. Wide variety of convolutions and logical operations on images available including histogramming.

FF1 Frame Grabber

Input:

RS-170 or CCIR

Memory:

up to 1024x1024x16 bits image memory.

Bus:

Half-size XT slot.

Processing:

Analog Devices ADSP 2105 DSP (20 MOPs). Performs 3x3 convolution in 390 ms.

Other:

Library of C callable functions, and windows DLL. Very inexpensive -- $995.

[real-time frame buffers and imaging analysis] [need address]

Dipix offers 3 general purpose frame-grabbers:

XPG-1000 Power Grabber

Input:

RS-170, CCIR, digital, or programmable. Multiple input modules.

Memory:

up to 256Mb of image memory, 512Kb cache

Bus:

ISA/VL and PCI bus

Processing:

50 Mhz TMS320C40 DSP from TI (which is programmable in C) and 'Power Processing Module' with on-board ALU, CONV, and HIST.

Other:

Optional real-time display

Input:

4 analog or one 8 or 16-bit digital input, programmable, or RS-170, RS-330, CCIR.

Memory:

up to 80Mb (4 min)

Bus:

ISA/VL

Processing:

TMS320C30 DSP from TI (which is programmable in C). DT-Connect bus.

Other:

Realtime display available

Input:

Same as XPG-1000

Memory:

512kb to 8 MB 0 wait state SRAM

Processing:

TMS320C44 DSP from TI (programmable in C)

Other:

real-time display card available software compatible with above models

ImageNation makes video frame grabbers in a variety of configurations and options.

ImageNations Website is located at ImageNation

CX100 Precision Video Frame Grabber

The CX100 Video Frame Grabber is a precision image capture board in the ISA bus configuration. It is an 8 bit, half slot card ideal for compact applications. Compatible with monochrome video in either NTSC or CCIR formats. Allows real time capture to dual port video RAM mapped into the computer's memory. This provides fast, random access to the captured image for even the most demanding image processing needs. The image transfer rate is 1 Mbyte per second. The CX100 also has a display output for viewing live video or a captured image on an external monochrome monitor. Analog RGB, 30 Hz interlaced video output is an option available for false color display (this is not VGA compatible). In addition, there is a trigger input for synchronizing image acquisition to an external event or for operation with an asynchronous (resettable) camera.

The CX100 is a +5 volt only design. It consumes less than three watts and has a power down mode. The all digital synchronization scheme provides a rock solid image and an +/- 3 nS sampling jitter specification. Video noise is less than one LSB (least significant bit). The automatic detection of NTSC or CCIR video, coupled with the excellent jitter performance, ensures operation with standard and resettable cameras as well as video recorders. Hardware controlled field or frame grab, software adjustable offset and gain, automatic look up table (LUT) load and non-volatile configuration is supported. Input and output LUTs allow gamma correction, contrast and brightness adjustment, and thresholding in real time. The optional overlay RAM allows text and graphics to be displayed on top of live video or a captured image. The video overlay can display 15 LUT selectable colors (gray levels).

Lots of software support is also provided. Software and examples are available on ImageNation's BBS.

ImageNation ImageNation also offers versions of the CX frame grabber in the compact PC/104 format. PC/104 is the familiar ISA bus in a compact, low power, 3.6 X 3.8 inch format. It is ideal for embedded applications. ImageNation supports multiple camera and display applications with a four to one video multiplexor available in ISA or PC/104 versions. Contact ImageNation today for more information.

Offers a modular vision system that can be taylored for the application. Both VME and PC ISA/VL-bus platforms are supported. It seems likely, however, that when all the required modules are selected, the system will have a fairly large pricetag.

A system consists of an 'image manager' or IML which is either a VME or PC ISA/VL-bus compatible board. It contains some framstore memory and a slot for the 'acquisition module'. For the PC version, the IML can be used as the system VGA adapter, eliminating the need for a separate display card or module. To add one of the many available computational modules, the 'Computational Module Controller' or CML must be purchased, which also plugs onto (sort of) the IML. The CML has slots for either one or two plug-on computational modules. So, as you can see, it adds up quick. About $23k for a system with 2 C31 DSP computational modules. Device drivers are available for DOS/Windows, VxWorks, OS-9, and Solaris.

There are 4 available acquisition modules:

1. Variable Scan: interfaces to RS-170 and CCIR cameras
2. Fast Analog Acquisition: interfaces to high frame rate analog cameras
3. Color Acquisition: interfaces to NTSC, PAL, RGB or multiple RS-170/CCIR cameras. One interesting feature of this module is the ability to program your own color space. Otherwise, it supports HSI, YUV, YIQ and YCrCb color spaces.
4. Digital Acquistion: interfaces to RS-422 or TTL video sources.

1. Convolver/Arithmetic Logic Unit (CM-CLU): Accelerates convolution. e.g. a 4x4 convolution on an 8-bit 512x512 image takes 7.5 ms.
2. Programmable Accelerator (CM-PA): Contains a TMS320C31 DSP from TI (which can be programmed in C), 4Mb image memory and 1Mb of EEPROM.
3. Histogram/Feature Extraction Processor (CM-HF): Performs realtime histograms and feature detection.
4. Median and Morphological Processor (CM-MMP): performs morphological filtering, erosion, and dilation.
5. Binary Correlator (CM-BC): Performs high-speed template matching and binary morphology.

SMART EYE I: DSP-based real-time image processing system designed specifically for mobile and fixed base robotics systems. Stand-alone image processing system on a single board. Low power consumption, small form factor, and low weight. The single board system includes: four monochrome camera inputs, video digitizer (gain and offset software adjustable), input look-up table, two frame grabbers, additional two video buffers, color mappable image display buffer, color mappable graphics overlay buffer, RGB display driver, serial communications port, and application program RAM and EPROM. Program code can be burned into EPROM. Wide variety of language and development platform support. Additional hardware expansion to provide addtional I/O capabilities.

The IMAGE series consists of the following mutually compatible hardware:

• IMAGE-1280 Baseboard consists of a TMS34020 GSP, TMS34082 FPU, 4Mb of DRAM, custom ASICS for fast data transfer, and a high resolution RGB display driver.
• IMAGE-ASD is a monochrome acquisition card that plugs into the ISA bus.
• IMAGE-CLD is a color acquisition card that does realtime RGB to HSI conversion and also plugs into the ISA bus.
• IMAGE-RTP performs a whole slew of processing functions using a bunch of ASICS (e.g. histograms, LaPlacians, morphologies, logical operators, erosion, dilation, centroids, pattern matching, more)
• IMAGE-FPU accelerates large kernel convolutions and FFTs

The basic system that Sharp offers is the GPB-1

Input:

4 multiplexed RS-170 inputs 8 bit greyscale. Optional 'Incard' allows 3 parallel camera inputs, or one RGB input, but occupies another ISA slot.

Memory:

12 512x512x8 bit framestores.

Bus:

ISA

Processing:

High-speed ASICS which perform convolution, histogram analysis, feature extraction, connectivity analysis, more. These operations all take place at 40 ns/pixel. Thus, for example, a 3x3 convolution takes 12 ms for a 512x512x8 bit image. Other processing boards (see below) are available and external interfaces are provided for the addition of a separate Alacron i860 card with 80 Mflops of performance (available 2/95).

Other:

VGA output for displaying images. An optional 'Single monitor adapter' acts as the system VGA adapter.

1. Alignment card: performs normalized correlation with model data.
2. Auxlut card: has dual 64k 16 bit input 8 bit output lookup tables. A possible application would be RGB to HSI conversion.
3. Auxwarp Card: 'a pixel re-sampler that may be used to modify the geometric shape of an object.'
4. Memory Mapping: Maps large amounts of image data to ISA bus and allows random access of regions of interest, say. Also it allows new GPB-1 commands to be loaded in and ready to go while the GPB-1 is busy with its current command. Occupies a separate ISA slot.

The basic GPB-1 system costs $11,000. A system with an Incard, and Auxlut runs around $20,000.

URL: http://teleos.com/ Advanced Vision Platform, AVP-100 provides:

• stereo range measurements
• motion measurements
• 3D model-based object tracking
• video frame rate performance

Connect to http://teleos.com/ for more information or send e-mail to info@teleos.com with the subject 'AVP-100'. TIM-40 PC-based Vision Systems
There are about a handful of companies that support TIM-40 module platforms. (TIM-40 is a specification developed by TI and industry to incorporate the TMS320C40 into a flexible, modular architecture. A single TIM-40 module is 2.5" x 4.2".) The C40 is often referred to as a 'next generation transputer' because of its six 20Mb per sec. comports which make connecting multiple C40s together very easy. The speed at which data can be exchanged makes it well suited for multiprocessor image processing. A system consists of a computer host-specific motherboard (that the TIM-40 modules plug into) and the appropriate TIM-40 modules. All companies listed below support both VME and PC/ISA daughter boards, however, only the PC/ISA boards are described. Since these systems typically consist of more than one processor, development software that supports multiple processors would be nice. 3L Parallel C is an ANSI C compiler that allows you to write multitasked software and divide the tasks between the available processors at compile time. It's built ontop of the TI C compiler which is known for its optimizing and efficient instruction scheduling. Data is sent between arbitrary tasks (which may reside on separate processors) by sending C structures. Thus, the development environment is comfortable and intuitive. All companies listed offer 3L Parallel C.

TIM-40 PC/AT motherboard: 4 TIM-40 sites. Communication between one TIM-40 slot and PC takes place through 1K FIFO buffer. JTAG support for debugging. RGB/Composite framegrabber module: occupies 2 TIM-40 slots and accepts RS-170 RS-330, CCIR, NTSC, PAL, Y/C or RGB. Has an onboard 50Mhz TMS320C40 (50 MFLOPs). 3Mb of VRAM and up to 4Mb of DRAM is available. Flexible Memory TIM-40: occupies 1 TIM-40 slot, has onboard 50 Mhz TMS320C40s (50 MFLOPs) and up to 4Mb of DRAM. Dual C40 TIM-40: occupies 1 TIM-40 slot, has 2 onboard 50 Mhz TMS320C40 (100 MFLOPs) and 512k SRAM per processor. Display TIM-40: allows display of RGB images.

QPC40 Motherboard: 4 TIM-40 sites. Communication between any of the 4 TIM-40 slots and the PC takes place through 2 16 bit ISA bus locations (one for transmit, one for receive) per TIM-40 slot. JTAG support for debugging.

RGB/Composite framegrabber module: occupies 2 TIM-40 slots and accepts RS-170 or RGB. Has an onboard 50Mhz TMS320C40 (50 MFLOPs) and a RAMDAC for displaying RGB images. 32kb of EEPROM, 512kb of SRAM, and up to 16Mb of DRAM is available. Currently, (11/94) this module is not supported by 3L Parallel C, nor does it have framegrab software source available.

Several single C40 TIM-40 modules are offered that differ in memory models -- some have EEPROM for boostrapping, or up to 8Mb of DRAM offered on a single TIM-40, or up to 65Mb od DRAM on a double TIM-40.

Dual C40 TIM-40: occupies 1 TIM-40 slot, has 2 onboard 50 Mhz TMS320C40 (100 MFLOPs) and 512k SRAM per processor.

Spectrum also offers ILIB -- an image processing library with routines to perform convolution, LaPlacians, high and lowpass filtering, more.

HEPC2 Motherboard: 4 TIM-40 Sites. Communication between one TIM-40 slot and the PC host takes place through 2 16 bit ISA locations (one for transmit, one for receive). JTAG support for debugging.

CFG-RGB framegrabber module: occupies 2 TIM-40 slots and accepts RS-170 or RGB. Has an onboard 50Mhz TMS320C40 (50 MFLOPs). 1Mb of VRAM framestore and 4Mb of DRAM memory onboard. Frame grab software and source is provided.

VIPTIM convolution accelerator: occupies 2 TIM-40 slots. Contains a 50MHz TMS320C40 and ASICs that can convolve at 12.5 million pixels per sec. with kernels up to 7x6 or 14x3. 3, 1Mb VRAM framestores and 4Mb DRAM memory onboard.

HETwin dual C40 TIM-40: occupies 1 TIM-40 slot, has 2 onboard 50 Mhz TMS320C40s (100 MFLOPs) and 512kb SRAM per processor. Similar model with 2 C44s and 1Mb SRAM per processor will be available early 95.

HEQUAD quad C44 TIM-40: occupies 1 TIM-40 slot, and has 4 onboard TMS320C40s (200 MFLOPs) and 512kb SRAM per processor.

Traquair also offers the following software:

EYELIB: image processing library (different than ILIB (?)) that performs convolution, histograms, logical operations, more.

CDSOFT: a utility that works with 3L Parallel C that allows the display of RGB image data to the PC host's VGA monitor in less than realtime.

Mathlib: a math library accelerator for the C40 that in many cases more than doubles the speed of some floating point calculations (e.g. sin).

Matlab interface: allows an arbritrary C40 processor to execute functions in Matlab (that's running on the PC host).

This area of communication is changing very quickly and new products and companies are appearing every day.

See also a nice list at: [LIST IS NO LONGER THERE - AWAITING NEW SITE] ftp://csd4.csd.uwm.edu/pub/Portables/Wireless/wireless-modems or gopher://csd4.csd.uwm.edu List Maintained by David Kent, dkent@world.std.com

Comrad, Communications Research and Development Corporation

Cylink

GRE America,

Hamtronics, Inc.

Micrilor Inc

Monicor Electronics

Motorola Radio-Telephone Systems Group

Pacific Crest Corporation

Proxim, Inc.

They are distributed through Anixter. For local Anixter offices call 708.677.2600. We've used a number of the ARLAN products for years at CMU and it's been plug and play.

Proxim Inc.

Digital Ocean

Grouper wireless networks. Spread-spectrum (no FCC license) 902-928MHz. Several products for Macintosh computer.

Also see the file regularly posted to sci.electronics and a number of the radio newsgroups: ftp://rtfm.mit.edu/pub/usenet/sci.electronics/ Roger Arrick also has a web page listing supplies of gears, bearings and parts at: http://www.robotics.com/mechpart

All Electronics Corporation

Allied Devices

American Science and Surplus

These guys are a good source for motors, steppers, wire, and lots of gears, pulleys, etc. stuff for robot people to roll their own robots as well.

Arrick Robotics

C&H Sales

Digi-Key Corp

Edmund Scientific

Electronic Goldmine

Fascinating Electronics

Graymark

Herbach and Rademan Co.

Hosfelt Electronics

JDR Microdevices

Microwave doppler radar sensor. Claims to detect a person or animal up to 12' away (part number RK-MD3, $19.95 w/o case. Claims to come with complete circuit theory and instructions.

Marlin P. Jones

McMaster-Carr Supply Company

MECI

Mendelson Electronics Co., Inc

Newark Electronics

Nordex

PIC Design

Radio Shack

SECS, Inc.

Seitz Corporation

Servo Systems

Small Parts Inc.

Stock Drive Products

Surplus Center

Any technical library should have catalogs from the larger distributors. These include McMaster-Carr, Grainger, Allied, Newark, etc.