Brief: Teaching electronics, physics and computing in schools is a real challenge, as it can be difficult to get children to engage with some of the abstract concepts involved. Design a automated sumo fighting robot for a target market of your choice. Produce an operating prototype to fight in a contest against other students.
Duration: 5 Month Level 2 Coursework. Team of five; Chris Green, Satthaporn Barnes, Christina Lombers, Simon Wagstaff and Si Lui. Everything shown is my own work.
Skills shown: Electronics, Teaching
Result: A sports car themed design such as this Ferrari 250 GTO style automated sumo fighting robot with searching eyes, an attack ramp and defence feelers. Designed as package circuits and equipment to be put together by 10-15 year olds and then be put in the ring. In competition my robot got knocked out in the semi finals.
(Robots pictured by Kyle Langdridge)
Focus Group and User Evaluation:
The Impact detector must allow our robot to detect impact from the opponent in order to prevent them from knocking our robot out of the ring. This circuit allows the robot to manoeuvre out of the way when it feels impact. It can feel impact on both the X and Y axis meaning that if are robot is hit on the front, back, left or right this circuit will detect that impact.
The competition would be done in a black ring with a white line around the edge that if you went out of you would lose. Therefore this circuit kept the robot from leaving the ring. We used. The IR Detector should allow the robot to distinguish the difference between white or black surface depending on the amount of light being reflected from the IR Emitter as the white surface would be more reflective. The Comparator will convert the analogue output signal from the white line detector circuit to a digital output signal to get a cleaner reading for the robot.
The proximity sensor works by infra-red emitter and a line of detectors that allow the device to measure distance by triangulation. The closer the object the near the light bounce back is to its source. This causes the voltage to increase the nearer the opponent is to our robot and therefore allows our robot to ‘see’ the opposition.
Momentary switches are used here to detect the impact on the robot car from the opponent.
The basic concept of the feeler was to provide the car robot with another defence strategy. We decided to put the switches in parallel to create a binary logic OR function. This means that only one of either 3 switch needs to be in contact for the circuit to work and the robot to move in the forward direction.
An RC servo like this can rotate 180 using pulse-width modulation to control the motors position. This was used to rotate the proximity sensor so that the ‘eyes’ would not be stationary, which means that it can ‘search’ for the opponent rather than just happing to come across it.
To programme the robot I first had to first decide on all the actions of the robot when the various sensors are hit as well as its normal course. I used state diagrams followed by flow charts for this. After I had decided everything the robot was going to do then I started programming on Labview using a National Instruments MyDAQ on the robot to link up the components of the robot and the computer.