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In this lab, the team did further testing on the final developed code, and observed the energy efficiency over multiple tests. One complication of this lab were the data results received regarding the efficiency figures. The power output ranged no less than 300 and no more than 350, which are high numbers in terms of mass to power output ratio. While team F continues to work on adding final commands to the working code, the power efficiency is proving to be a difficult challenge. This issue is being overcome with less propellor work over the same period of time. The team is changing the code to promote more “gliding” of the AEV when it breaks, which decreases the amount of power needed to quickly and shortly reverse the AEV in order to stop it. Another issue originates from inconsistent AEV performance on the track during testing. After two to three tests, the AEV begins to fall short in distance and speed, and changing the battery to satisfy energy needed to run the AEV also tends to be met with over/underestimates in absolute position lengths in the code and the overall speeds of the AEV when reversing and going straight. The team is working on obtaining data on the voltage of the battery in use, and seeing how it changes over the course of the lab period to determine the true source of the error before final testing.

In order to follow the MCR objectives while having the most efficient vehicle, the team plans to make progress with the current lab setup; Testing the code and troubleshooting based on data received through the arduino. In terms of the physical aspect of the AEV, the team has decided to maintain the current prototype as the final model. As discussed in the previous lab, the team was working on the final code independent of monitoring the energy efficiency. The overall main goal for the team was to develop a code that meets all of the criteria given for final testing. Now that a working code has been developed, the team used this lab to not only tweak the code to compensate for any small errors in timing or speed, but have also used the lab time to now improve the efficiency figures produced by the AEV. While the team is observing similar efficiency levels as past labs, finishing the final code allows them to devote more attention to decreasing the overall power output. Regardless of the ultimate outcome of the power efficiency troubleshooting, the working code will be tested next week.

The team was able to further develop a process to make quick changes to the code in order to move closer to the final test/run. Other takeaways regarding the code included being able to see relationships between the motor speeds and the power output, and how the team could potentially decrease the output and promote a higher energy efficiency. This takeaway, while beneficial to the team’s overall performance, has been difficult to implement in the physical AEV model due to energy it takes for the AEV to carry the R2 unit back to the original position. The team has also overall been able to maintain a strong system of delegation seen in the first stages of the lab, working independently while still being able to come together with our ideas and conclusions and continue to develop a cohesive AEV product.

In Lab 9, Team F utilized trial and error to discover which combinations of codes and physical designs will provided the most energy efficient option for the AEV. Mainly focusing on the functioning code, the team observed how the energy output and overall propeller efficiency changed with different combinations of code. While the team was able to find a clear balance of push and pull with the propellers to produce the best efficiency, there were technical issues with the performance of the AEV with the code provided. The team spent a majority of the lab time doing small scale troubleshooting to develop a code that mirrored the final criteria of the lab (stopping at the gate, picking up the R2D2, pausing at the right times, etc.). This aspect of the lab came unexpectedly to the team, as the code created in the previous lab ran according to the final code criteria effectively. The team inspected the AEV and code, comparing it to any observations in the last lab in attempts to identify where the inconsistencies may have originated. No clear conclusions were made, though the team expects the code made in Lab 10 to run identically in future labs.

Differences in the code can be seen in how the arduino stops on the track. The team has chosen two methods to stop the AEV on the track. Either entering a brake command into the code prior to approaching the gate to account for coasting on the track, or making the motors reverse when the AEV gets to the gate to eliminate coasting and create a quicker brake time. The code that causes the motors to reverse is preferred because it gives the team more control over how and where the AEV stops on the track, however, it is less efficient than simply letting the AEV coast. Goals for the next lab are focused on making the Arduino perform according to the criteria of the MCR. All tests on efficiency and changes to the overall body of the AEV are generally concluded, so insuring the AEV runs perfectly is the main priority. Team F has, however, seen a constant increase in efficiency in the AEV as changes are made, and plan to continue to build upon these improvements until the final test/run, even though this may not be the main focus of these final labs. Currently, aspects that have increased efficiency are the placement of the propellers on opposite sides to promote the “push” and “pull” system, centralizing the weight of the arduino and battery, and configuring the propellers on vertical segments below the body of the AEV which has increased aerodynamics and consequently the efficiency as well. The team is completing a full circuit on the track by breaking the code into parts. The team is using comments in the code to break it down, and once one section performs sufficiently on the track, the team moves onto the next section of code. Essentially, each part of the track (performance before, during, and after the gate) will be performed in pieces of the code and will run accordingly.

Takeaways in terms of the AEV body originated from the positioning of the propellers. The team has made final decisions on the size/amount of material being used for the AEV body, however positioning of external parts are still being discussed. There was still a slight lean around the corners, and the team which will also become a factor of re-positioning external parts and testing to try and eliminate these errors. All coding takeaways can be seen in the ability for the team to quickly change the power output and absolute position in efforts to fill the criteria of the MCR for the final code.