The AEV was run on a monorail track using two black lines to indicate where the AEV should stop. The AEV would begin towards the middle of the track and move backwards along the track to pick up the cart. The AEV would then proceed to the other end of the track, making stops along the way, to let the passengers off. Afterwards, the AEV went back to the other end to drop off the cart and continued back to the starting position as seen in figure #. Each run was documented so that adjustments could be made easier. Each stop was recorded to see what kinds of adjustments were needed and how they could be made.
Each design was compared to the reference design by using two methods learned in class. Five criterias were considered during the comparison. After using the screening method, as shown in table 1, design B seemed to be a better design out of three designs. However, with the scoring method design A is the better design. As shown in table 2, each of the criterias were weighted and reconsidered. Since a concept scoring matrix provides a better resolution than a screening matrix, design A was picked and built for the start of the project.
| Success Criteria | Reference | Design A | Design B | Design C |
| Cost | 0 | – | 0 | 0 |
| Complexity | 0 | – | 0 | 0 |
| Weight | 0 | – | + | 0 |
| Balance | 0 | 0 | 0 | 0 |
| Originality | 0 | + | – | – |
| Sum +’s | 0 | 1 | 1 | 0 |
| Sum 0’s | 5 | 1 | 3 | 4 |
| Sum –’s | 0 | 3 | 1 | 1 |
| Net Score | 0 | -2 | 0 | -1 |
| Continue ? | Combine | No | Yes | No |
Table 1: Concept Screening Scoresheet
| Reference: Example | Design A: Manta | Design B | Design C | ||||||
| Success Criteria | Weight | Rating | Weighted Score | Rating | Weighted Score | Rating | Weighted Score | Rating | Weighted Score |
| Balance | 20% | 2 | 0.4 | 3 | 0.6 | 2 | 0.4 | 2 | 0.4 |
| Weight | 20% | 3 | 0.6 | 2 | 0.4 | 3 | 0.6 | 3 | 0.6 |
| Cost | 5% | 3 | 0.15 | 2 | 0.1 | 3 | 0.15 | 3 | 0.15 |
| Originality | 40% | 1 | 0.4 | 4 | 1.6 | 1 | 0.4 | 1 | 0.4 |
| Complexity | 15% | 3 | 0.45 | 2 | 0.3 | 3 | 0.45 | 3 | 0.45 |
| Total Score | 2 | 3 | 2 | 2 | |||||
| Continue? | No | Develope | No | No | |||||
Table 2: Concept Scoring Scoresheet
| 3 Blade Pusher | |||||||||
| Voltage | Current | Thrust | Power | Thrust Calibration | RPM | Power Input | Power Output | Propulsion Efficiency | Advance Ratio |
| volts | amps | grams | % | grams | RPM | Watts | Horsepower | % | – |
| 0.37 | 0.12 | 181.90 | 10 | 0.25 | 841 | 0.02 | 0.01 | 33% | 2.81 |
| 0.74 | 0.19 | 181.90 | 15 | -0.16 | 1501 | 0.07 | 0.00 | -7% | 1.57 |
| 1.11 | 0.28 | 183.70 | 20 | 0.99 | 2160 | 0.16 | 0.03 | 19% | 1.09 |
| 1.48 | 0.37 | 189.00 | 25 | 3.16 | 2819 | 0.27 | 0.09 | 34% | 0.84 |
| 1.85 | 0.46 | 195.40 | 30 | 5.80 | 3478 | 0.43 | 0.17 | 40% | 0.68 |
| 2.22 | 0.57 | 198.60 | 35 | 7.11 | 4137 | 0.63 | 0.21 | 33% | 0.57 |
| 2.59 | 0.67 | 204.50 | 40 | 9.54 | 4797 | 0.87 | 0.28 | 32% | 0.49 |
| 2.96 | 0.78 | 211.30 | 45 | 12.33 | 5456 | 1.15 | 0.36 | 31% | 0.43 |
| 3.33 | 0.90 | 220.00 | 50 | 15.91 | 6115 | 1.50 | 0.47 | 31% | 0.39 |
| 3.70 | 1.00 | 223.20 | 55 | 17.22 | 6774 | 1.85 | 0.51 | 27% | 0.35 |
| Thrust at 0 (g): | 181.9 | Velocity (m/s): | 3 | ||||||
| Blade diam. (m): | 0.0762 | ||||||||
Table 3: data for three blade propellers.
Figure 1: propulsion efficiency vs. advance ratio for three blade propellers.
| 2 Blade Pusher | |||||||||
| Voltage | Current | Thrust | Power | Thrust Calibration | RPM | Power Input | Power Output | Propulsion Efficiency | Advance Ratio |
| volts | amps | grams | % | grams | RPM | Watts | Horsepower | % | – |
| 0.37 | 0.12 | 181.90 | 10 | 0.08 | 1052.23 | 0.02 | 0.00 | 11% | 2.69 |
| 0.74 | 0.19 | 180.90 | 15 | -0.33 | 1876.25 | 0.07 | -0.01 | -14% | 1.51 |
| 1.11 | 0.28 | 183.70 | 20 | 0.82 | 2700.28 | 0.16 | 0.02 | 16% | 1.05 |
| 1.48 | 0.37 | 187.90 | 25 | 2.55 | 3524.31 | 0.27 | 0.07 | 27% | 0.80 |
| 1.85 | 0.46 | 191.90 | 30 | 4.19 | 4348.34 | 0.43 | 0.12 | 29% | 0.65 |
| 2.22 | 0.57 | 196.30 | 35 | 6.00 | 5172.36 | 0.63 | 0.18 | 28% | 0.55 |
| 2.59 | 0.67 | 201.60 | 40 | 8.18 | 5996.39 | 0.87 | 0.24 | 28% | 0.47 |
| 2.96 | 0.78 | 207.10 | 45 | 10.44 | 6820.42 | 1.15 | 0.31 | 27% | 0.42 |
| 3.33 | 0.90 | 213.20 | 50 | 12.95 | 7644.44 | 1.50 | 0.38 | 25% | 0.37 |
| 3.70 | 1.00 | 219.30 | 55 | 15.45 | 8468.47 | 1.85 | 0.45 | 25% | 0.33 |
| Thrust at 0 (g): | 181.7 | Velocity (m/s): | 3 | ||||||
| Blade diam. (m): | 0.0635 | ||||||||
Table 4: data for two blade propellers.
Figure 2: propulsion efficiency vs. advance ratio for two blade propellers.
The original design A used the two-blade propellers. After tested both of the propellers, the data from tests were compared. The highest efficiency of 3 blade was 40%, but the highest efficiency of 2 blade propellers was 29%. Also, comparing the propulsion efficiency vs. advance ratio graph of figure 1 and 2, with the same advance ratio the three blade propellers always have greater efficiency. As the result two blade propellers on the original design was replaced by three blade propellers for better performance.
Figure 3: Power vs. Time with seven phases for design 1
| Phase | Arduino Code | Time(seconds) | Total Energy(J/kg) |
| 1 | celerate(4,0,25,2); | 7.74 | 182.26 |
| 2 | motorSpeed(4,20); | 4.68 | 85.53 |
| 3 | brake(4);/goFor(2); | 2.1 | 93.56 |
| 4 | celerate(4,0,30,2); | 7.2 | 322.88 |
| 5 | motorSpeed(4,15); | 3.36 | 105.05 |
| 6 | celerate(4,0,flat,3); | 14.16 | 254.23 |
| 7 | goToAbsolutePosition(s2); | 1.8 | 60.53 |
| Table 5: arduino code, time and total energy of each phase for design 1. | Total Energy Used: | 1101.01 | |
Figure 4: Power vs. Time with six phases for design 2
| Phase | Arduino Code | Time(seconds) | Total Energy(J/kg) |
| 1 | celerate(4,0,25,2); | 6.36 | 160.10 |
| 2 | motorSpeed(4,20); | 0.96 | 23.65 |
| 3 | brake(4);/goFor(2); | 16.44 | 583.80 |
| 4 | celerate(4,0,30,2); | 10.08 | 152.40 |
| 5 | motorSpeed(4,15); | 18.90 | 571.39 |
| 6 | celerate(4,0,flat,3); | 1.80 | 36.01 |
| Total Energy Used: | 1491.35 | ||
Table 6: arduino code, time and total energy of each phase for design 2.
During performance test 1, two designs were developed and compared to be the final design. Both of the designs of AEV was evolved from the original design A. The difference between two designs was design 1 have the tail wing on the back, design 2 does not. The tails wings on the back of the AEV was take off to improve the balance and provide a better center of mass to satisfy aerodynamics. Also, the cost of the AEV was reduced because less pieces are needed. The angle of the side wings were adjusted to be lower to make sure the propellers would not hit the track. Also, the side wings were moved backwards to provide a better balance since the battery is attached toward the front of the AEV.
Under the same control program, the two concepts of AEV behaved a little differently. Design 1 seemed to accelerate faster and had less travel time than design 2. However, it is hard to tell if there were major effects from the battery while they were tested. The power vs. time graphs for both design looked very similar. Design 2 took longer time to reach the stop position of design 1. The power vs. time graph for design 1 was divided into seven phases as shown in Figure 3 and Table 5, and the total energy used by design 1 was 1101.01 joules per kilogram. Design 2 was divided into six phases as shown in Figure 4 and Table 6, and the total energy used by design 2 was 1491.35 joules per kilogram.
Figure 5: Power vs. Time with phases for final run.
| Phase | Arduino Code | Time(s) | Total Energy(J/kg) |
| 1 | celerate(4,0,24,2) | 7.38 | 175.52 |
| 2 | celerate(4,0,30,2) | 12.48 | 327.39 |
| 3 | motorSpeed(4,16) | 13.54 | 394.70 |
| 4 | celerate(4,0,flat,3) | 10.02 | 444.83 |
| 5 | goToAbsolutePosition(s2) | 11.19 | 424.64 |
| 6 | celerate(4,0,36,3) | 10.2 | 91.27 |
| 7 | celerate(4,0,flat,2) | 15.84 | 405.57 |
| 8 | celerate(4,0,22,2) | 8.82 | 119.48 |
| 9 | celerate(4,0,flat,2) | 13.33 | 214.14 |
| Total Energy Used: | 2597.60 |
Table 7: Phases and energy of each phase.
Figure 5 and Table 7 shows the results from the final run of the AEV. It was divided into nine phases. Total energy used was 2598.60 joules per kilogram. Compare to the previous tests results the total energy used did increase because of the extra weight added onto the cart. During the performance tests, coding strategy was improved based on data obtained and calculations. The final run was quite successful. Although some stop points were a little off due to influence from the battery, the AEV did perform as expected.