Battery Testing Procedure
Purpose: Test the relationship between power usages, distance traveled, and total battery voltage. Whether a fully charged battery performs better than a half-charged battery.
Background/Setup:
- Testing will be done with Group K’s current AEV design, if changes to the design arise they will be disregarded during this testing.
- Code for the test will cause the AEV to move at 35% power for 3 seconds then brake all motors and reverses all motors for 3 seconds at 35%.
- Attempting to investigate the final mission parameter of power usage based on voltage left in battery.
Procedure:
- Begin with fully charged battery.
- Record voltage
- Run AEV on track
- Use AEV Extraction tool to retrieve power usage and distance traveled from run.
- Repeat steps 2-3 for 10 trials, recording battery voltage before each run.
- Afterwards, compile all power usage results. Distance traveled, and battery voltage.
Results:
“insert photo”
This graph shows the voltage of all ten runs stacked up against one another.
This graph take the average voltage of each run, then plots them in order. The battery initially started out at 8.12 volts for the first run and decreased to 8.05 volts for the tenth run.
Conclusions:
Over the length of ten runs, the voltage only dropped 0.07 volts. While the second graph makes the decrease look dramatic, overall it is not. The voltage drop did not effect overall performance. Therefore, there is not worry of the battery not working by the end of an aev run.
Reflectance Sensor Test Procedure
Purpose: Test how to increase reflectance sensor accuracy or reduce inaccuracy.
Background:
- Experiment will completed with Group K’s AEV Design.
- Test 1 Code will have the AEV travel for 2 seconds at 35%
- Test 2 code will have the AEV run at 25% and 35% for 125 marks ( ~60 inches)
Procedure:
Test 1: Starting on Strip vs Not on Strip
- Set AEV on Track at beginning of Track, placing wheel with mirror strip off sensor
- Run code sequence, taking AEV off track once it has stopped moving.
- Extract recorded distance data with Extraction Tool
- Perform 10 trials for off the mirror strip and 10 while on the mirror strip
Test 1: Data
The graph shows the difference in the runs starting off or on the reflective tape. The average difference between runs is 3.3 marks. Note that the graphs cross
Test 1: Conclusion
Starting on versus off the tape does not make a difference. The graphs cross showing that the same distance was reached on versus off the tape. This denotes that there is no difference between the two.
Test 2:
- Set AEV at beginning of track.
- Run 35% power code sequence, recording the marker at which the propellers stop spinning.
- Stop the AEV on the track after the above value is recorded.
- Complete the procedure again using 25% power code sequence.
Test 2: Data
These tables are the recorded distances for the 35% and 25% runs. The measured versus actual distance is the difference between the start of the tape measure and where our AEV counts. The next column over takes the actual distance traveled divided by the theoretical. The bottom in green is averages.
Test 2: Conclusions
The difference between 35% and 25% was 2.9 inches with the 35% going farther. This shows that the faster the AEV went the less accurate it was. However it is not by a large factor. What was discovered is the mark per inches was not what was stated in the arduino documents. It was in fact double the amount. This was used to to mark a new inch to mark conversion factor.
Advanced R&D 3 Procedure
Objective: Determine the cost differences between using 30%, 40%, and 50% power in order to determine most efficient power to use in final code.
Procedure
- Create code for ½ of full run using only 30% power
- Complete 5 trials of the run, timing using stopwatch
- Extract power usage from run
- Then create code using 40%
- Complete 5 trials of run, timing with stopwatch
- Extract power usage from run
- Repeat same steps for a code with 50% power
- Once all tests are complete, compare total costs from the runs to determine most efficient power percentages
Data
Discussion
This test shows a very high correlation between running the motors at a higher power and using less energy and. The jump from 30%-40% had huge savings in both categories. The jump from 40%-50% did not have a change in overall time, but energy efficiency was increased.
Conclusion
Going forward motor speed will be set to 50% for optimal time and energy use.