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Robotics projects always interest me when I was doing engineering studies in my polytechnic and university days.  As a result, I was involved in robotics for my polytechnic final year project, University robotics challenge and University Industrial Attachment Programme.

The first robot we created was pretty neat.  It was a robotic shooter that used ultrasonic sensors to determine the location of the target.  The shooting mechanism consists of two small but powerful German made motors with spongy rollers attached to the shaft.  Ammunitions came in the form of ping pong balls and a motorized mechanism was developed to push the balls between the rollers which were rotating in counter directions.  The effect was a powerful shoot which was 95% consistent for a maximum distance of approximately 6 metres.  Apart from the three motors in the shooting mechanism, a 5.25" floppy disk drive motor was used for the elevation of the ping pong ball propeller.  To move around, the robot could only move left and right on a rail with the help of another larger motor.  Hence, the target is one dimensional like a flat target board.  I was one of the programmers of this robot and it was powered by a Motorola 68HC11 microcontroller. 

This was the first generation robotic shooter.  At that time, the supervisors were planning for a second generation shooter, based on the experiences learnt from the first one, for the upcoming batch of final year students.  The second generation robotics shooter was supposed to shoot in indirect projections and move around in both axis.  I did not follow up the outcome of it when I graduated from the polytechnic.  Overall, I had a lot of fun in the project!  It was a huge project as 13 students from the Electronics Department and the Mechatronics Department put their hands and minds together to build two totally different first generation robotic shooters and a target system.  Our project was selected to participate in the Commex 96 Exhibition for outstanding performance.

My second robot was an obstacle avoidance robot built from used items such as kinex blocks, 5.25" floppy disk drives motors, standard issued components and leftover components from other projects.  Only the analog-to-digital converter (ADC) chip need to be purchased.  The purpose of building this robot was to participate in the University Robotics Challenge.  Although we were given a substantial budget for the project, we wanted to built an environmentally friendly robot that uses recycled materials.  Moreover, its kind of fun going through our used stuff and building this robot from it. 

The robot will move in a maze and move towards a light source (in this case, a lamp).  In order to "see" obstacles, there were four infrared transceivers, each on one face of the robot, installed to detect obstacles.  One conventional infrared transceiver consists of a infrared transmitter and receiver.  If there was an obstacle in front, the infrared signal emitted by the transmitter will bounce back to the receiver.  The analog signal was converted into digital signal by the ADC and this data could be fed back to the processor to decide if there was an obstacle in front.  The processor used here was the laptop pentium processor connected to the robot via parallel port interface.  To locate the lamp, there were three "eyes" on top of the robot looking at the -45°,0° and +45° directions.  I designed the sensory circuits for the robot.  In robotics, we often had the "offset" problem in infrared sensors due to the ambient light from the environment.  I had devised a way of getting around this problem. E-mail me if you are interested to know about the details.

The third robotics project was more technologically advance as it could hear, speak, see, move and shoot projectiles.  This babe is something to talk about!  At the heart (or rather hearts) of this robot, there are three interconnected Texas Instruments digital signal processors (TMS320C31).  They performed complex tasks such as fast fourier transform, speech recognition, image processing and servo driving with the capability of communicating with each other.  This mobile robot (The Defender) has abilities to receive instructions, in the form of speech, from a human operator as well as having the intelligence to operate independently.  The robot was able to "see" using the Visual System which includes an digital video camera.  To display such capabilities, we programmed the robot to seek out a moving target (using three acoustics sensors and visual sensor) and accurately hit the target with its onboard projectile system.  The robot will be able to take in voice commands and respond in English. 

I was personally responsible for the robotics vision and RF uplink system (Yes, you could monitor the status of the robot and target on a computer through the RF uplink system).  During the development stage, only one programmer can access the robot at a time (there were four of us!).  I had to create an additional developmental platform for the visual system (first picture from the left) to avoid jamming for the use of the robot.  The robot is shown above from the second picture onwards (from left).  It had four megabytes RAM onboard, attached through SIMM32 sockets.  This robot was the result of three FYP and five Industrial Attachment Students' effort!

Last Updated 4 June 2001