In this week’s lab, the team experimented with the efficiency of the AEV. The team did this by constructing different aspects of the code and comparing the energy used. The team mainly experimented with the difference in coasting vs reversing in slowing down the AEV. The team experimented with this in the path from the start to the gate. The team found two codes that the got to the gate with the two different methods as described above. Then compared the energy and the performance. The coasting method took significantly less energy since the motor was running for less time and the motor was not used to slow down the AEV. However, the performance of the coasting method was much less consistent since the battery can play more of a factor in the coasting method, and so can the friction and wind. The team does not want to have to sacrifice the performance and completion of the mission for the energy efficiency of the AEV. The team therefore went forward with the reversing of the motors to slow down the AEV at the gate. The data can be seen below:
The red line, showing coasting, has an energy consumption of 49 joules. The blue line, showing reversing, has an energy consumption of 66 joules.
The two runs have virtually the same energy consumption leading up to the finish, which is where the coasting uses significantly less power. The team liked having the knowledge and understanding that there is a way to reduce the energy consumption of the AEV, but the team had to continue pursuing the completion of the mission. The team went ahead with the reversing of the AEV to slow itself down to have a consistent method of stopping at the gate. The team then went ahead and started to work on code to complete the mission. Within one day, the team had already gotten to the additional vehicle. In the next two days the team worked on taking the additional vehicle from the foam block to the gate on the return trip.
At the end of Lab 10, the team had successfully made it through gate one, picked up the additional vehicle, and then inconsistently made it back to the gate for the second time.
The graph of the most recent run is below. It consumed 235 joules of energy and got to the gate, but didn’t stop in the right place at the gate. This run is good representation of what the successful of the AEV will look like. The energy consumption is much greater in the third part of the graph since the AEV must carry the additional vehicle.
Takeaways:
- The team found that energy efficiency is attainable but it comes at a decrease in consistency
- The completion of the mission is attainable, but it is still unclear if the team will complete the mission
- The team worked very well this week and is glad they have been a team all semester