Cons and Pros for Each Design
*All designs are uploaded at https://u.osu.edu/engr1188sp18section6731groupb/labs/creative-design-thinking/
Design 1
Pro – Compare to the reference design, design 1 is with pulley instead using propellers. So, it has better movement.
Con – Almost having a similar value of safety compared to reference design, It’s not good at stability and durability.
Design 2
Pro – It’s good at stability compared to reference design because Arduino and battery are well positioned to balance the weight. Movement, durability, and maintenance are even at reference design.
Design 3
Pro – Compare to the reference design, design 3 is better at stability and maintenance.
Con – Although even at movement and durability compared to reference design, It’s not that good at safety because panel with propellers is too close to other board.
Design 4
Pro – Compare to the reference design, design 4 is better at stability and movement.
Con – Although even at durability and maintenance, it is not good at safety.
Design 5
Pro – Design 5 is good at stability, movement and maintenance compared to the reference model.
Con – Almost even at durability, it is not good at safety.
Screening and Scoring matrix
Both screening and Scoring matrices below are made up of six criteria which are stability, movement, durability, safety, maintenance and efficiency. Stability, as an evaluation standard, stands for ability to balance weight of designs. Movement stands for how the designs move on the track without blockage. Durability is used to check ability of a physical product to remain. Safety is used to determine how safe the AEV when it is on the track. It has lower score when it has more probability to get off the track. Maintenance is an evaluation standard that checks a design by process of keeping it in good condition. Last evaluation standard is an efficiency which evaluate how a AEV model moves efficiently without wasting energy. The Team B’s goal is to try to higher an efficiency of AEV, so percentage of the efficiency is the highest among six criteria in scoring matrix.
Screening matrix
Scoring matrix
Conclusion
When screening five designs compared to reference design, Design 2 and Design 5 get 2 highest +. And when scoring five designs, Design 5 gets 3.55 while Design 2 gets 3.25. So, Design 5 will proceed to the lab. Design 5 is good at stability, movement and maintenance compared to the reference model. But we need to develop its durability and safety which is even and worse than the reference model. Therefore, Design 1 and Design 5 were chosen to be developed. Afterwards, Design 1,by lab, was proved that it has more efficiency than Design 5 has. However, Design 1 with pulley system has some limitations. First, pulley sometimes slipped away and didn’t go well on the track. Second, because pulley didn’t fit perfectly with two wheels, the AEV model was not balanced when it moved. So, the Team decided to change propulsion from pulley system to gear drive. The process of evolution in the AEV model can be found at https://u.osu.edu/engr1188sp18section6731groupb/e-aev/evolution-of-design/
Takeaway
The biggest take away from the lab is that the scoring method can filter out more designs than screening method can. As above figure, although screening method can’t distinguish which design is better when more than one designs have same net score, scoring method can decide two designs which can be used to next lab using rating and weighted score.