The assembly and final construction of the robot took place this week and it was a bit of a roller coaster.
With the circuit complete we began writing the code for the robot. One of the team members spent alltuesday evening trying to trouble shoot some of our issues (eg code wrote to chip but with no response from the motors) we were able to take measurements to prove the sensors worked, although the left range finder cone over heated and we hadnt enough experience/understanding to alter the code appropriately so we decided to remove it.
Luckily for us though the issue lied only in not enough power for our motors. John was able to write the code and see it progress with an LED board (there were 4 LEDS, 2 per motor in oppoing bias to represent direction of motors) and with the introduction of a bigger capacitor to smooth out the main supply and a dedicated supply on the power chip for the motors.
Wednesday we committed to the final assembly of the robot. We fitted both the battery packs, sensors and circuit board and hallelujah we had a robot that made it to the table and did what it was supposed to.
Well almost…with the wedge down everything worked as normal but we had an issue with flipping it down as in its fighting state It exceeded the dimensions (so it flipped up 90° which can be seen in images in a previous post below) firstly we tried altering the code but the resistance to it lied in the looms for the black/white sensors. They didnt have enough room to retract into the main body thus holding it up. The wedge getting stuck proved to be a bigger issue than just loosing our main attack method but with our black/white sensors positioned in it it nedded to collapse fully so we could maneuver the board effectively. We decided to then remove the wedge as it was offsetting the amount of contact and therefore traction the wheels were getting.
It was from this point the robot went down hill. In trying to move and shorten the sensor looms we accidentally cut one of them so we had to solder in a replacement and the choice was made to instead use the other (uncut) sensor as it was to cut it also and put in a new one.
For some reason we lost power to one and when measuring the voltage out on the other we were getting crazy values (7.4V + down as low as 2.3V+) which were fine and didnt effect the sensor but unfortunately with the way the chip works (0 to 2.3V is classified as low and assigned a binary 0 value and 2.3V to 6V is classified as high and assigned a binary 1) we werent dropping the input signal voltage low enough for the chip to read it as a drop and output a 0.
We tried to troublshoot it but with the clock ticking we made an executive decision to just run the motors with delays.
Something happened in the middle that resulted in when the (dedicated) supply was taken off the motors one kept turning at high speed. When the supply was re-introduced the motor that was previously on stopped and the other began to spin furiously.
We forefittef our first math to allow us more time. We checked wiring, supplys, replaced the micro controller (although the other one when tested had power and could be written to), re-wrote the code etc but unfortunately nothing rectified it.
With time well and truly ran out we had to have something compete so we crossed our fingers and hoped our special little bot wouldn’t be demolished.
We managed to win some of our matches due to other teams throwing themselves off the board, lack of activity or we were closest to the center of the arena when time ran out.
For the standard of robot that we ultimately submitted we somehow managed to get to 7th place. By the end though after loosing a few matches (only due to disqualification) we ended up 9th which for what made it to the table is pretty impressive.