To qualitatively compare the different AEV designs, design matrices were utilized. The success criteria chosen were: stability, weight, lengthwise balance, use of space, safety, and aerodynamic. The stability of the AEV takes into account the motor placement and angle, the distance of the motors to the center of mass and the weight distribution from side-to-side. The team rated the different designs based on how more efficient each criteria was in comparison to the reference sample AEV. For example, the sample had zero aerodynamic components. If the different designs included some form of aerodynamic, a higher rating would be given. The more aerodynamics the design, the higher the rating. All other success criteria were judged in this mindset. In regards to safety, it’s related to the stability and balance of the AEV. If the stability and balance are low, the safety is also low.
For the Concept Screening, designs were given a “+”, “0” or “-” (i.e. good, neutral, bad rating) for each criteria and the total amount of each sign was tallied and used to decide which designs the team were to keep or combine. Similarly, the Concept Scoring was based on a 1 to 5 rating scale (i.e. 1 is the lowest, 5 is the highest). Each criteria was also given a percentage weight, and the weighted score of each criteria for each design was calculated and total. Based on the design matrices, the team’s AEV and member, Ian Risser’s AEV will be carried forward in the design cycle.
Table 1: Concept Screening
Table 2: Concept Scoring
Pros and Cons of Each Design
Designed by Ian Risser
This design took into consideration aerodynamics, and lengthwise balance of the AEV, thus receiving higher ratings in this category. The overall design is also very stable and safe. However, since the aerodynamic component was added, it is an additional weight.
Designed by Jerry Ding
This design solely focuses on making the AEV as aerodynamic as possible. However, since only the aerodynamic components were emphasized and the other criteria were ambiguous, only the aerodynamic criteria scored a high rating.
Designed by Mai Nguyen
This design is based on the sample AEV, but focused on the stability, lengthwise balance and use of space which the sample had lacked. Though this design received high ratings in these criteria, there was no aerodynamic component considered.
Designed by Lei Yang
This design focuses mainly on the aerodynamics of the AEV. Though in comparison to the sample has higher ratings in majority of the criteria, it received lower ratings in lengthwise balance and weight because the AEV parts are all concentrated at near the center of mass. The aerodynamic component also added more weight.
Team Design
The team design took all the best parts of each member’s design. The aerodynamic, usage of space, stability and lengthwise balance criteria were heavily focused on. The design was aimed at simplicity and efficiency, so at this point of R&D, had no considerable con.