After over
10 designs, countless new ideas, and revisions of separate components, our team has refined our AEV to its final, optimal design. Through theory crafting, rapid-prototyping, and frequent performance analysis, our team has designed and implemented several uniquely designed components which work together to provide our AEV its supreme speed and energy efficiency, while simultaneously ensuring low production costs.
The first major aspect of our design’s success is the use of two propellers affixed to a single motor. When compared to a more traditional dual motored AEV, the use of a single motor not only decreases energy consumption by nearly 30% and saves significant production costs, but also, by affixing two propellers onto a single motor, energy efficiency increased by another 15%. As well as being more efficient, using a single, centrally located motor increases the safety of our design, as there is less propeller overhanging the design that may be dangerous to the local populous or environment. It also decreases the noise pollution produced by the AEV considerably.
The second major aspect of our design is the use of a servo motor as a brake. By using a servo brake, braking speed and precision both improved drastically, thus allowing the AEV to travel much more quickly while still stopping safely and smoothly. It was also a major factor in reducing the design’s energy consumption, as braking using the motor uses a mere fraction of the energy needed to run the motors in reverse for the duration needed to stop with the same precision attained by the servo brake. Not only that, but it avoids the major energy consumption spikes that occur whenever a motor is reversed in polarity, as instead of reversing twice each time the AEV is braked, the motor only needs to be reversed once as it reaches the end of the track.
The third major aspect of our design is the use of modified wheels. It was noted early in the construction of AEV that a wheel constructed using all 12 of the available ball bearings produced far more friction than a wheel with only 9 included. In a rough test, we found a normal wheel spun with moderate force would spin for around 2.0 seconds while a wheel with only 9 bearings spun with the same force would spin around 4.1 seconds, more than twice as long. This improves the coasting distance of the AEV substantially, and allows the AEV to accelerate from rest more quickly, as well as to accelerate using smaller amounts of power. As a result, the total energy consumed decreased drastically. This aspect was discovered during initial testing of Performance Test 1, which initially used around 90 Joules of power. After the removal of these bearings, the same test was completed using 41 Joules of power.
The employment of these three primary design features, as well as an iterative process of physical design and code optimization resulted in outstanding results in the final AEV application. The graph below is an analysis of the Time vs. Power Consumption of the AEV during Final Performance Testing. The AEV completed the test in 44.6 seconds and used a total of 120.48 Joules. These results, as well as the cost saved in the construction of the AEV culminated in a final cost of $494,683.40. This cost achieved our team’s personal goal to be below $500k, and was well below the assigned budget of $600k.
