Week 5 Physically building the robot.
Set the mood, tensions are high, 2 days before the race and everyone is eager to build the final robot. So on Wednesday evening our team decided to go to the work shop after class. We had a design in mind. The minute we set foot in the work shop and tried to apply our design there was a problem with the front axle. The second that happened I knew we under estimated the difficulty that would come with physically building the robot. The issue arose when the front axle couldn’t be pushed back far enough leaving our 10 by 10 design in peril. After several other attempts mounting the axle and a flat plate it was already closing time. This really began to worry me as we only had 1 more day. So being the only one in the group with I took the project home and said I’ll stay up tonight and try work something out.
So when I got home I tried a few more designs and the closest I got to mounting a main plate and an axle was when I spaced the back and front of the plate of the motor with nuts and place the axle in between the plate. This looked promising but then I seen the motor itself was dragging on the ground leaving the wheels hanging in mid-air.
It was 2a.m and I finally had enough of trying. I decided to go to bed and as I was falling asleep I had a brain wave that brackets with holes should be hanging from t the plate and the axle goes through the holes under the motor itself meaning we could push the wheels as far back as possible. I got up and it only took me an hour to do. I was then back up at 7 and had only 2 classes on the Thursday so I spent more time finishing the robot where I mounted the colour sensor at the back and the switch at the front which gave me no problems. I then met up with my group and we fitted a metal box strapped on the plate, in that was the battery pack and on top was the breadboard. The design was finished!!!!!
The above notion sounds great but it was actually 5pm the day before the race and nothing was tested. We didn’t start off very well as there was no voltage coming out of the pin for one side of the motor. We eventually got it working by simple putting in a 10k resistor to ground. The robot was finally running and the colour sensor, switch and code were working perfectly but after many trials we still couldn’t get the robot under 20 seconds. We finally got it on 20secs give or take. We then went back to basics adding in another capacitor on the 6volt side to stop noise and cleaned up the circuit as the chip was only giving out 2.5 volts at best causing such a slow speed hoping it was just a loose connection. We then thought it was down to the chip constantly resetting due to the high pitched screaming from the motor. We then asked for the assistance off Ted and David as we felt like we did everything and after 4 hours of trouble shooting we called it a day on 20seconds. Ted diagnosed the motor being damaged……………
This news was quite a disappointment as the amount of effort was for nothing and that our whole design was based on a broken motor. But I will say I learnt a lot though and that was a good lesson on how much work it takes for the bare minimum to build a robot and to get started straight away on the next robot task. I’m hoping our next design will be a bigger success. Below was our abomination