Our final design is shown below.
The data from the final performance test is seen below.
As seen in figure above, the amount of power used during the run was consistent, which means the chosen propeller configuration was the best choice. The run was 52.5 seconds long, which was about the fastest it could be since there was no time wasted during coasting. The budget was a main factor in the final performance test. Alterations were made from the previous performance tests in order to cut down on costs. A main factor in the budget was energy used, as seen in the table below.
Due to the research conducted during the previous performance tests as well as the research and development stage, the AEV was able to finish the final performance test accurately, so there was no accuracy multiplier in the final budget evaluation. The decisions to use the puller propeller when carrying the caboose back made the run as energy efficient and power braking made it as fast as possible. However, with the average cost of an AEV being $571,450, the AEV was way above the average with a total of $606,940. The capital cost was a little below the average of $161,737, however the AEV used 311 Joules while the average was 219 Joules, this was the main reason the AEV was over budget. The average times were very similar, so that was not a big factor in the budget. Power braking, while accurate and faster than coasting, is not very efficient because it requires short bursts of high energy to stop the AEV from moving. An observation made during the final tests was that a servo motor brake used a lot less energy, and was just as accurate as power braking. If given more time, the servo motor would have made the cost for the AEV decrease dramatically.
Code Used:
| reverse(4); | //reverse the polarity of the motors |
| motorSpeed(4,42); | //motor speed set to 42% for both motors |
| goToAbsolutePosition(210); | //the AEV runs the previous command till sensors record tick 210 |
| reverse(4); | //motors reverse polarity |
| goToAbsolutePosition(260); | //AEV waits until it reachs tick 260 to run next command |
| motorSpeed(4,35); | //motor speed set to 35% for both motors |
| goFor(1.1); | //runs for 1.1 seconds as a power brake |
| brake(4); | //cuts power to the motors |
| goFor(7); | //waits at gate for 7 seconds |
| reverse(4); | //motors reverse to prepare for leaving the gate |
| motorSpeed(4,42); | //motor speed set to 42% for both motors |
| goToAbsolutePosition(450); | //motors run until tick 450 |
| brake(4); | //cuts power to the motors |
| reverse(4); | //motors reverse polarity to prepare for power brake |
| goToAbsolutePosition(618); | //next command runs when AEV reaches tick 618 |
| motorSpeed(4,35); | //motor speed set to 35% for both motors |
| goFor(1); | //runs command for 1 second |
| brake(4); | //cuts power to the motors |
| goFor(5); | //waits for 5 seconds |
| motorSpeed(4,41); | //motor speed set to 41% for both motors |
| goToAbsolutePosition(410); | //runs until tick 410(moving back towards gate) |
| reverse(4); | //the motors reverse preparing for power brake |
| goToAbsolutePosition(381.8); | //next command runs when AEV reaches tick 381.8 |
| motorSpeed(4,44); | //motor speed set to 44% for both motors |
| goFor(1.4); | //power brakes for 1.4 seconds |
| brake(4); | //cuts power to the motors |
| reverse(4); | //reverse the polarity of the motors |
| goFor(6); | //waits for 6 seconds |
| motorSpeed(4,43); | //motor speed set to 42% for both motors |
| goToAbsolutePosition(256); | //runs till tick 256 |
| reverse(4); | //reverse the polarity of the motors |
| goToAbsolutePosition(130); | //runs next command at tick 130 |
| motorSpeed(4,40); | //motor speed set to 40% for both motors |
| goFor(2.5); | //power brakes for 2.5 seconds |
| brake(4); | //cuts power to the motors |