As the semester moves forward our design will evolve. This page’s purpose is to show the different stages of designing AEV prototypes and to also show off our team’s overall design process. This includes our first prototype, team design sketch and an analysis of estimated costs for each design (Table 1).
Prototype AEV Design: 1
Our team’s first design was a prototype pre-designed to give the team the ability to test functionality of the motors and sensors. Displayed below is our prototype constructed.
[figure 1. Assembled AEV (Top View)]
[figure 2. Assembled AEV (Side View)]
[figure 3. Up close view of reflectance sensors]
[figure 4. SolidWorks assembly of design 1]
Prototype AEV Design: 2
Our team’s second design is similar to the first design with the major difference being the use of straight wings and no brackets. This decision was made to lower the total cost of the AEV and use less parts.
[figure 4. Prototype AEV Design 2]
The basic idea behind Design 2 was to test the possibility of scaling down to a single motor. The design consisted of 2 motors, each mounted on one side of the AEV. Each wing is rectangular shaped. The center gravity was concentrated in the middle, giving balance to the AEV. The weight was also distributed along the two wings of the AEV. This balance distribution of the weight was crucial to give the stability to the AEV. The two motors were powerful enough to function the AEV the way it was supposed to.
Prototype AEV Design: 3
[figure 5. Prototype AEV Design 3]
For Design 3, the team removed the trapezoid fins and angle brackets to further streamline the AEV. The overall structure of this design is lighter and more aerodynamic than Design 2. For thrust, this design uses a single motor, which should allow it to carry the amount of material needed. The downside to this design is that the small frame of the AEV may make it less stable.
Estimated Cost of Designs:
Table 1: Parts Used per Design and Total Cost
| Component ($ Unit Cost) | Design 1 | Design 2 | Design 3 | Design 4 | Final Design |
| Arduino ($100,000) | 1 | 1 | 1 | 0 | 0 |
| Electric Motors ($9,900) | 2 | 2 | 1 | 0 | 0 |
| Servo Motor ($ 5950) | 0 | 0 | 0 | 0 | 0 |
| Count Sensor ($2,000) | 2 | 2 | 2 | 0 | 0 |
| Count Sensor Connector ($2,000) |
2 | 2 | 2 | 0 | 0 |
| Propellers ($450) | 2 | 2 | 2 | 0 | 0 |
| T-Shape ($2,000) | 0 | 0 | 0 | 0 | 0 |
| X-Shape ($2,000) | 0 | 0 | 0 | 0 | 0 |
| 2”x 6” Rectangle ($2,000) | 0 | 0 | 0 | 0 | 0 |
| 2.5”x 7.5” Rectangle ($2,000) | 1 | 1 | 1 | 0 | 0 |
| 1”x 3” Rectangle ($1,000) | 0 | 2 | 0 | 0 | 0 |
| 1.5”x 3” Rectangle ($1,000) | 0 | 0 | 0 | 0 | 0 |
| Trapezoids ($1,000) | 2 | 0 | 0 | 0 | 0 |
| L-Shape Arm ($3,000) | 1 | 1 | 1 | 0 | 0 |
| T-Shape Arm ($3,000) | 0 | 0 | 0 | 0 | 0 |
| Wheels ($7,500) | 2 | 2 | 2 | 0 | 0 |
| Battery Supports ($1,000) | 1 | 1 | 1 | 0 | 0 |
| Motor Clamps ($590) | 1 | 2 | 1 | 0 | 0 |
| Angle Brackets ($840) | 3 | 0 | 0 | 0 | 0 |
| #55A Slotted Strip, 2″ ($1,260) | 0 | 0 | 0 | 0 | 0 |
| Bulk Screws & Nuts ($0) | 1 | 1 | 1 | 0 | 0 |
| Total Cost Estimation: | $154,810 | $150,290 | $140,390 | $0 | $150,290 |
Creative Design Process:
( Team G AEV Orthographic Sketch(Design 1))
The basic concept behind Design 1 is to create a design which is lightweight and simplistic. The main goal for this design is affordability. The design uses a single 2″ x 7.5″ platform, a L-Shape Arm and two Trapezoids as the main structure. For thrust, this design uses both motors, which allows it to carry the amount of material needed without issue. The downside to this design is that the small frame of the AEV may not provide enough cargo space for the unit. If this is the case, the bigger t-shape frame will be added to the AEV. This would raise the cost by roughly $2,000.
Concept Screening and Scoring:
Table 1, shown below provides the concept screening excel table the group made to decide the final AEV design. Table 3 has five success criteria. The first is stability; this criterion is important because if the AEV does not remain stable, it will undoubtedly fall off of the track causing damage to the AEV. Next success criterion is blockage; this is important because if the AEV has obstructions, it will not be able to maneuver around the track. Maintenance is important to the AEV design because if the AEV is too complicated and time-consuming to repair it will become more of a burden to its intended than an asset. Safety is similar to maintenance in that the AEV will not be a useful tool if it’s too unsafe. Finally, the last success criterion is durability. Durability is because in the case of a crash the group does not want the AEV to break completely, causing hours of setbacks. Using these five criteria, the group judged each of the AEV designs and compared them to the reference AEV. Using these criteria, the group narrowed the design options down to Bahjat’s design and Jayson’s design before proceeding to the concept scoring method. These two designs were selected mainly because of their superior stability, durability, and low maintenance needs. Patrick and Tyler’s designs were not used due to their increased obstruction, lack of stability, and inferior durability compared to the sample AEV.
[table 3. Concept Screening]
After completing the concept screening, the group moved to concept scoring. (results are located in Table 4 To perform the concept scoring the team placed weights on each of the success criteria above. Safety and durability were given the most importance at 25% because the main goals the group have for the AEV is to make it safe to use and resilient enough to be used in the environment. Stability was worth 20% because if the AEV’s stability scored low, the whole project could be compromised. Finally, Minimal blockage and maintenance were given lowest importance at 15% because they are the group’s lowest concern, but still important enough totake into account. Using these guidelines, the team decided the best to design would likely be Jayson’s.
[table 4. Concept scoring]
Final Design:
The final design chosen for the final performance test for the AEV was design 2 after the research and first 3 performance tests in the research tab, and due to its ability to complete the objectives listed in the MCR and the advantages over the other AEV’s listed in the sales tab.