Group D — Paul Crock, Joshua Dakwar, Alicia Sanders, Megan Sanders Progress Report 2
Instructor — Richard Busick, GTA — Ben Richetti 3/20/2019
Report of Progress
Situation
Lab six began the Advanced Research and Development 1 (aR&D 1) part of the AEV design process. During this lab, the team collaborated with their company, Koffolt Properties, to decide on what types of research investigations to conduct. The group chose to test coasting versus power braking as well as battery testing. The team also had its first committee meeting during lab six. During the meeting, the team discussed their progress regarding the AEV design process with the Smart City Team and in turn, received helpful advice on how to improve.
The next team meeting was lab seven. During this lab, the team discussed how the data for the two research investigations would be collected. For the coasting versus power braking investigation, it was decided that the team would test how far the AEV traveled with a given speed and distance. To test the battery, the team decided to keep track of the change in battery voltage after one lab period, which is approximately fifty-five minutes.
For labs eight and nine, the team researched coasting versus power braking. By the end of lab nine, the group finished collecting data for the investigation. The team also began trial runs of Performance Test 1. For the performance test to be considered a success, the AEV must be able to complete one main task, which includes making it to the gate between two sensors, pause for seven seconds while the gate opens, and then proceed through the gate.
For labs ten and eleven, the team continued working on Performance Test 1. By the end of lab eleven, the AEV was successfully performing the test. After completing Performance Test 1, the group started the Advanced Research and Development 2 (aR&D 2) part of the AEV design process, which was battery testing. It was necessary to perform a battery test to create a vehicle that is as energy-efficient as possible. An AEV that is energy-efficient was desired by the team because it would be less expensive to operate.
Result and Analysis
The first research investigation was the coasting versus power braking test (Appendix A). It was noticed that when the power was increased by 5%, the AEV coasted an additional 25 inches (50 marks) on average (Appendix B). This data showed the team that when the AEV needs to come to a stop, it would be more efficient to allow the vehicle to coast rather than use power braking because energy would be saved. It was also noticed that when coasting different distances at the same speed, the distance the AEV traveled was negligible, as a change of 10 marks resulted in less than three inches of coasting distance. This result proved that speed was the determining factor for the distance traveled.
The second research investigation was the battery test (Appendix C). The team kept track of the battery voltage over one lab period and noticed that the voltage decreased by about 0.05 Volts in approximately 55 minutes. The team also found that the amount of distance the AEV traveled did not have a significant impact on the battery voltage. A distance increase of 10 marks decreased the battery voltage by 0.001 Volts (Appendix D).
Takeaways
- As the speed increased by 5%, the AEV coasts 20.7 inches farther on average.
- As speed increases, the successive gains in distance coasted decreases.
- At a constant speed, changing distance has very little effect on coasting, only changing by about the difference in powered distance.
- During the course of one lab period (approximately 55 minutes), the battery voltage decreased by approximately 0.01 Volts.
- The amount of distance the AEV traveled did not have a significant impact on the battery voltage, however, as the AEV is powered for more distance, the voltage decreases faster over time
Future Work
Situation
The group’s next goal is to complete a successful run of the second performance test. This performance test will require the AEV to complete the task required for the first performance test as well as a second main task. As soon as the AEV proceeds through the gate, the second main task begins. This task requires the AEV to travel to the loading zone and successfully connect to the load using a magnetic hitch without the AEV bouncing past the loading line. The AEV must then pause for five seconds to ensure that the cargo loaded safely, and then exit the loading zone. After the first and second performance tests, the team will start focusing on completing a rough draft for the Critical Design Review, as well as completing the third progress report. Finally, the team’s focus will be on completing the third and final performance test. To successfully complete this performance test, the team must complete an additional two tasks on top of the two that were required for the second performance test. Once the AEV exits the loading zone after pausing for five seconds, the AEV will need to return to the gate without the hitch disconnecting during the elevation change (Appendix E). Next, the AEV must pause at the gate between the two sensors for seven seconds. This will conclude the third main task. The fourth and final main task requires the AEV to continue to the starting dock after the seven-second pause at the gate. The elevation will change at this point, so once again, this must be performed without the hitch disconnecting. The AEV must then stop past the starting line at the starting dock.
The reason why these performance tests are important is because the AEV will need to stop at specific locations to allow passengers to board and exit. These performance tests allow the team to fine-tune the AEV’s code to ensure the safety of the passengers.
Upcoming Goals
The next goal for the group is to successfully complete Performance Test 2. This test will be the same as Performance Test 1 (Appendix F), except after the AEV proceeds through the gate it must connect with the load, pause for five seconds, and then exit the loading zone. Successful completions of these tests will show that the team’s AEV design is capable of performing the tasks needed when transporting its passengers. After Performance Test 1 and 2 are completed successfully, the next goal for the team will be to complete the Critical Design Review, which will be a lab report covering the research and design process of the team’s AEV. Once the lab report is finished, the group’s goal is to complete its third progress report. After the progress report, the team’s goal is to complete the Final Performance Test. A successful completion of this performance test would mean that the AEV would be able to move from the starting dock and stop between the gate sensors, wait there for seven seconds, proceed through the gate, connect to the load without recoiling out of the “loading zone”, pause for 5 seconds, return to the gate without disconnecting from the load, stop between the gate sensors and pause for 7 seconds, proceed through the gate, and then finally stop at the “starting dock”.
Upcoming Schedule
3/20/19 at 11:15 AM – Team will conduct Performance Test 1
3/21/19 by 11:10 AM – Team will complete Website Update 3
3/21/19 at 11:10 AM – Team will present R&D Oral Presentation
3/27/19 at 11:15 AM – Team will conduct Performance Test 2
3/28/19 by 8:00 AM – Team will complete Team Evaluations
3/28/19 by 11:10 AM – Complete rough draft for Critical Design Review (CDR)
4/04/19 by 11:10 AM – Team will complete Progress Report 3
4/08/19 at 10:20 AM – Team will complete a draft of Final Oral Presentation
4/11/19 at 12:30 PM – team will conduct Final Performance Test
4/18/19 by 8:00 AM – Team will complete final Team Evaluations
4/18/19 by 11:10 AM – Team will complete Critical Design Review (CDR)
4/18/19 by 11:10 AM – Team will complete final update for the website
Appendix
Appendix A: Codes for aR&D 1
//run all motors at 25% power for 125 marks
motorSpeed(4,25);
goToRelativePosition(125);
//run all motors at 30% power for 125 marks
motorSpeed(4,30);
goToRelativePosition(125);
//run all motors at 35% power for 125 marks
motorSpeed(4,35);
goToRelativePosition(125);
Appendix B: Graphs and tables for aR&D 1, Coasting tests
This graph shows how the AEV travels over a constant powered distance of 25% power for 125 marks, resulting in a final position of 249 marks, meaning 124 marks coasted
This graph shows how the AEV travels over a constant powered distance of 30% power for 125 marks, resulting in a final position of 307 marks, meaning 182 marks coasted
This graph shows how the AEV travels over a constant powered distance of 35% power for 125 marks, resulting in a final position of 336 marks, meaning 211 marks coasted
| Power: | 25% | 30% | 35% |
| Distance Coasted: | 124 marks | 182 marks | 211 marks |
Table summarizing all the data gathered, at a powered distance of 125 marks
| Distance Powered: | 91 marks | 106 marks | 125 marks |
| Distance Coasted: | 180 marks | 201 marks | 216 marks |
Table showing how distance coasted changes with changing powered distance, at 30% power
Appendix C: Codes for aR&D 2
//run all motors at 30% power for 40 marks
motorSpeed(4,30);
goToRelativePosition(40);
//run all motors at 30% power for 50 marks
motorSpeed(4,30);
goToRelativePosition(50);
Appendix D: Graphs and tables for aR&D 2, Battery tests
Graph showing the voltage decrease over 40 marks at 30% power, with an average voltage of 8.141 Volts, and a slope of -.0116 Volts/second
Graph showing the voltage decrease over 50 marks at 30% power, with an average voltage of 8.134 Volts, and a slope of -.0219 Volts/second
NOTE: as the 40 mark test was conducted earlier in a testing day than the 50 mark test, the .007 Volt decrease is a result of battery drain over time, and is indicative of how the voltage decreases after successive runs
Appendix E
Appendix E: Shows the elevation changes that the AEV will travel through during the performance tests
Appendix F: Code used for a successful run of the first performance test
// Run all motors at a constant speed (23% power) to 122 marks
motorSpeed(4,23);
goToRelativePosition(122);
//Brake all motors at 20 marks, then reverse
brake(4);
goToRelativePosition(16);
reverse(4);
//Run all motors at a constant speed (15% power) for 1.5 seconds
motorSpeed(4,20);
goFor(1.5);
//Brake all motors for 7 seconds
brake(4);
goFor(7);
//Reverse all motors, then run at a constant speed (25% power) to 40 marks
reverse(4);
motorSpeed(4,25);
goToRelativePosition(40);