Problem Background
The second test that was tasked to Team A was performing an energy analysis. An energy analysis generates calculations (in this case, using Microsoft Excel), with the goal of finding the forces acting upon an object. This type of analysis tells a bountiful amount about the AEV and its performance (regarding its energy efficiency). Team A’s job, after completing this energy analysis, is to then report the forces for other teams to unitize in their own AEV designs and calculations.
Plan
First and foremost, Team wanted to develop a clear-cut plan to provide the best and most reliable information for Company Scarlet. Throughout intensive research in the project’s documentation and many discussions between team members, and other division members, a definitive course of action was identified and set into motion. The following was the plan implemented for this specific test:
- Create a set scenario (using code developed by Team A) to run the AEV through; each trial having a different material attached (see the section titled “Code & Equations”).
- Calculate propeller force, friction force, and net force using the given Excel spreadsheet (see the section titled “Code & Equations”).
- Graph the AEV’s speed and distance traveled, in relation to time. In tandem with this, compare the results to other team’s designs (see the section titled “Results & Analysis”).
- Draw any conclusions and recommendations from the test that could be useful for Company Scarlet (see the section titled “Takeaways”).
Code & Equations
| Code | Comments |
|---|---|
| motorSpeed(4,30); | //Set all motors to 30% |
| goFor(4); | //Have the AEV run for 4 seconds |
| motorSpeed(4,0); | //Set all motors to 0% |
| goFor(10); | //Have the AEV run for 10 seconds |
Basic equations performed in Excel
Shown above is the Arduino code and important equations for the energy analysis (to learn about Arduino, see “Programming Basics” in “Phase One Development”). This particular scenario run makes the AEV move all motors at 30% speed for 4 seconds, and then have all the motors run at 0% speed for 10 seconds. This test case was chosen to get a variety of movement options for the AEV; making sure that the best material would be shown in all aspects of motion. Also, being a relatively short piece of code, it makes sure that the only thing being tested is the material, ergo limiting other factors of influence. The equations shown were important calculations performed in Excel; leading to propeller force, friction force, and net force. One note for these equations is that they only work for constant acceleration.
Results & Analysis
Below are the graphs that were generated from the data extracted during the energy analysis. The speed was measured in meters per second, the distance was measured in meters, and the time was measured in seconds. The Company Scarlet bar graph compares the net force of each team’s vehicle (measured in gram-force).
Speed v. Time & Distance v. Time Graphs
Force Comparison of AEVs in Company Scarlet
Takeaways
Conclusions
The resulting study showed that Team A’s current configuration, while better than the Phase One prototypes, provided the least amount of energy efficiency in Company Scarlet. Multiple things were noted, however, that led to a list of items that can increase the energy efficiency of an AEV, which includes examples such as:
- If certain tools are not necessary for the AEV’s performance, take them off so that the negative forces are lessened.
- The configuration of the AEV’s physical design matters. Specifically, weight reduction is directly proportional to energy efficiency.
- Allows further energy efficiency verification in the Performance Testing phase.
Errors & Feedback
While Team A believes that this data represents the best possible performance test of an AEV’s energy analysis, some points of error could have led to the data’s integrity being compromised. For example, the code utilized for this study was the same code utilized in the material testing. Using this code and not developing a separate test case could have skewed the data in favor of certain AEV designs. Another potential error that was possibly present was that of the team. One group member was not present for the energy analysis, and team roles were shifted around to work with this adjustment. This led to teammates performing roles for the first time, which ultimately could have interfered with the data. However, these errors were considered before undertaking this task, and were nullified in the preparation process.
Team A, after conducting this study, noted multiple changes that could be implemented to this test to make the overall experience better for any other team wanting to undergo an energy analysis of their AEV. Some of these notes include:
- The excel file could be organized in a better fashion; letting teams input their own data into a provided graph would help immensely in the structure.
- Some equations present in the Excel file were not explained in the best possible way.
However, the team believed there was enough guidance from upper management to complete the study with telling data.