Problem Overview
Propeller Configuration was the second test that Team B conducted in efforts to improve the efficiency of their AEV. For this test, the Team brainstormed some different variations in which they could orient the propellers to gather useful data. Using the most efficient motor configuration from the previous test, the Team selected a few based off of the two propellers provided(pictured below). The team collected the data and compiled some graphs comparing the input power with the distance the AEV traveled. Below is a description of each test case, the data collected, and the conclusions the team decided upon.
Test One
For test one, Team B first used the larger, grey propellers and oriented them facing the same direction, in a pull/push set up. The AEV would accelerate up to cruising speed, continue to move a constant speed for a few seconds before braking. Then reversing the motors to also collect the data while the AEV was moving in the opposite direction. Below is the code used for this test case.
| Code | Comments |
|---|---|
| celerate(4,0,30,2); | //both motors accelerate from 0% to 30% in 2 seconds |
| motorSpeed(4,30); | //both motors continue at power 30% |
| goFor(4); | //the previous action will last for 4 seconds |
| brake(4); | //both motors brake |
| reverse(4); | //both motors reverse |
| celerate(4,0,30,2); | //both motors accelerate from 0% to 40% in 2 seconds |
| motorSpeed(4,30); | //both motors continue at power 40% |
| goFor(4); | //the previous action continues for 2 seconds |
| brake(4); | //both motors brake |
All code commands are explained in the Arduino Code Glossary.
Test Two
For test two, the team continued with the larger, grey propeller and oriented them facing in the opposite direction, one push and one pull set up. The AEV would first reverse the single motor in which the propeller was facing in the opposite direction of the other, then the AEV would accelerate up to speed, continue at a constant speed for a few seconds before braking. Then both motors were reversed and the data was collected while the AEV moved in the opposite direction. Below is the code used for this test case.
| Code | Comments |
|---|---|
| reverse(1); | //reverses only one of the motors |
| celerate(4,0,30,2); | //both motors accelerate from 0% to 30% in 2 seconds |
| motorSpeed(4,30); | //both motors continue at power 30% |
| goFor(4); | //the previous action will last for 4 seconds |
| brake(4); | //both motors brake |
| reverse(4); | //both motors reverse |
| celerate(4,0,30,2); | //both motors accelerate from 0% to 40% in 2 seconds |
| motorSpeed(4,30); | //both motors continue at power 40% |
| goFor(4); | //the previous action continues for 2 seconds |
| brake(4); | //both motors brake |
All code commands are explained in the Arduino Code Glossary.
Test Three
For test three, the Team moved onto the smaller, orange propeller and oriented them facing the same direction. The AEV would accelerate up to cruising speed, continue to move a constant speed for a few seconds before braking. Then reversing the motors to also collect the data while the AEV was moving in the opposite direction. Below is the code used for this test case.
| Code | Comments |
|---|---|
| celerate(4,0,30,2); | //both motors accelerate from 0% to 30% in 2 seconds |
| motorSpeed(4,30); | //both motors continue at power 30% |
| goFor(4); | //the previous action will last for 4 seconds |
| brake(4); | //both motors brake |
| reverse(4); | //both motors reverse |
| celerate(4,0,30,2); | //both motors accelerate from 0% to 40% in 2 seconds |
| motorSpeed(4,30); | //both motors continue at power 40% |
| goFor(4); | //the previous action continues for 2 seconds |
| brake(4); | //both motors brake |
All code commands are explained in the Arduino Code Glossary.
Data
This graph shows the data collected from all three tests while the AEV was moving forward.
This graph shows the data collected from all three tests while the AEV was moving backward.
Conclusions
After collecting all of the data required for the testing, the Team separated and compiled the data into some useful graph in which they would be able to compare the data and extract which configuration was more efficient. It was first noted that another test involving the orange propeller was not performed and this was because, from the graph, the orange propeller barely even moved compared to the grey propeller and was noted that the collection would not be useful in comparison on the graph. After going over the rest of the data it was decided that the orange propellers were the least efficient in both directions. Looking at the grey propellers, they both performed in a similar matter and the decision would be close. Team B concluded that the larger, grey propellers, oriented facing the same way would be most efficient while moving forward. Although the graphs show that they were similar in performance, the overall distance traveled by the AEV, from moving forward and backward, was more efficient when the propellers were facing the same direction.