For the first performance test, the AEV had to start in the starting gate, travel up a slope, stop at a gate for seven seconds, and leave the gate. This task had to be accomplished with two different prototypes in order to find a superior model. Our group didn’t have many ideas going into the first practice runs for this test. We had decided to brake the AEV using air braking instead of the Servo motor. This was accomplished by reversing the motors at the point on a run where the AEV needed to stop. We also had a plan to use the goToAbsolutePosition function so that the AEV would perform all of its roles at certain points on the track. The specific numbers on the code were developed through trial and error. The two prototypes tested were the two angled motor configurations used in the motor configuration testing. The first was the angled out configuration, shown below.
The code used for this prototype is shown below.
motorSpeed(4,37); //run both motors at 37% power
goToAbsolutePosition(188); //continue until AEV has travelled 188 marks
brake(4); //stop both motors
goToAbsolutePosition(208); //coast until AEV reaches 208 marks
reverse(4); //reverse both motors
motorSpeed(4,32); //run motors at 32% power for 2 seconds (air braking)
goFor(2);
brake(4); //stop both motors
goFor(8); //remain stopped for 8 seconds
reverse(4); //reverse both motors
motorSpeed(4,30); //run both motors at 30% power for 2 seconds (exit gate)
goFor(2);
brake(4); //stop both motors
when preparing to test the second prototype, the angled in motor configuration, the code had to be altered because the AEV travelled too far and crashed into the gate. The code and a photo of the motor configuration are shown below.
motorSpeed(4,37); //run both motors at 37% power
goToAbsolutePosition(187); //continue until AEV reaches 187 marks
brake(4); //stop both motors
goToAbsolutePosition(207); //coast until a AEV reached 207 marks
reverse(4); //reverse both motors
motorSpeed(4,37); //run motors at 37% power for 2 seconds (air braking)
goFor(2);
brake(4); //stop both motors
goFor(8); //remain stopped for 8 seconds
reverse(4); //reverse both motors
motorSpeed(4,30); //run both motors at 30% power for 2 seconds (exit gate)
goFor(2);
brake(4); //stop both motors
Both prototypes completed the course successfully. There were no obvious differences between the runs of the two prototypes. Quantitatively, there was also little difference in energy used, distance travelled, and time for both prototypes. The energy used was slightly less in the prototype with the motors angled out, but the numbers were extremely close (66.979 Joules compared to 66.931 Joules). This energy difference wasn’t enough to conclude that the first prototype was superior, however the motor configuration testing showed that the prototype one was more efficient when it was travelling in reverse, a task that was not done in the first performance test. We believed that this observation would be consistent during the final performance test, so we decided that the prototype with the outward motor configuration should be used for the remainder of the project. The data from performance test one is shown below.
