EDISON the robot was a substantial leap from AMBER. EDISON was equipped with sophisticated infrared ranging sensors and simple photo sensors. EDISON would navigate through complex mazes and find a medicine box sitting on top of an aluminum can with a light bulb anchored to it. EDISON would get to the aluminum can, grab the medicine box which would shut the light off. Another alumnium can light would turn on at the opposite end of the maze. EDISON would navigate to the new light source and deposit the box on top of the can. EDISON was by far the biggest and most complex robot I've ever built. He stood about 2 and a half feet tall, weighed over 9 pounds, utilized over 129 wires, elicited 5 behaviors and sank over 57.6 watts of power. EDISON was an awesome robot. Specifications: Body - black-painted plywood base with 3 stackable layers Electronics - 1 BASIC Stamp II microcontroller unit, 1 BASIC Stamp stretcher board (no longer made), 1 Scott Edwards Mini Serial Servo Controller, 2 servos for backward facing gripper, 2 servos for pan/tilt camera system, 1 black and white CCD camera, 2 heavy duty DC brushless motors with wheel attached, 1 8-channel MAXX DUAL H-bridge motor driver circuit, 3 Infrared Rangefinders, 3 photo-voltaic cadmium sulfide photo sensors, 1 2x20 character LCD, 3 9V batteries (one for Mini SSC, one for STAMP2, one for B&W camera), 2 Ni-Cad 7.2v 2amp batteries wired in parallel for drive motors, 2x10 button keypad, RJ11 programming port, and 6 sensor activation indicator lights. Time to Build - 8 days Cost - $750 The design made for easy programming, disassembly, modification, expandability and durability. An RJ11 jack in a box was sticky-taped to the second level of EDISON's body. A 50 foot $3 phone line interfaced with the laptop for programming. You could expand EDISON by simply unscrewing the bolts on the four threaded rods and inserting another plywood plate. The frame was strong enough to carry a laptop onboard. One of the cooler parts of EDISON was the pan and tilt black and white CCD camera. The camera was a hacked FisherPrice: My first Video Camera toy for $30. Great for outdoor lighting, the camera had awfully good picture for it's price. The camera board easily interfaced with an AV cable to any standard TV or VCR input. Metal detection whiskers - the robot has 2 metal detection whiskers mounted on the lowest level of the robot in front of the battery box. Each whisker is curled over the other for maximum detection area. When both whiskers touch a metal surface, a circuit is made. The stamp registers an impact with a metal object by getting a +5v spike at the specified I/O pin. Photosensor - Three photosensors are mounted on top of the robots body. They each consist of a single cadmium sulfide cell, 1 .1mf capacitor, 1 220ohm resistor and 3 wires: 1 to +5v logic, 1 to ground and 1 as a signal line to the STAMP II processor. The stamp sends voltage through the resistor, then counts how long it takes to discharge, which is determined by the light level. In this fashion, the stamp can measure light levels. Each light sensor on EDISON had a corresponding green light to indicate light detection. Infrared Ranging Sensors - the IRPD unit was purchased at www.wirz.com and comes with a 4-wire j-connector. It occupies 2 I/O pins on the stamp. The onboard analog/digital converter sends back a digital byte value of 0 to 255 for distances 0 through 4 feet. Only additional parts were two capacitors and some diodes. Each IR sensor on EDISON had a corresponding red light to indicate obstacle detection. Motor Driver - MAXX DUAL H-bridge - The robot uses a single MAXX DUAL H-bridge motor driver board to drive the motors from a signal supplied by the stamp. Four wires are connected from the MAXX DUAL inputs to 4 I/O pins on the STAMP II. The four output pins on the MAXX DUAL H-bridge are hooked up to the motors, 2 leads each. By throwing input 1 high and 2 low, a motor hooked up to outputs 1 and 2 will spin. Reversing 1 and 2 will reverse the motors spin. The same applies to inputs 4 and 3, and outputs 4 and 3. The motor driver's supply is 2 7.2v 2amp Ni-Cad batteries. The motor batteries are optoisolated from the logic supply of the robot. The EDISON Robot was used in a series of experiments to test the Taskable SOAR controller. The successful results of the project were published in my Intel International Science and Engineering paper. EDISON won 4th place at the grand awards ceremony and over $2000 from corporate prizes. Visit my robotic homepage: Leonardo's Workshop on the Web www.ilrobotics.com -Leonardo 9-1-2000 Email: stiglie@aol.com