There were some interesting lessons that the team learned as a result of the second part of the project.  While we did better staying on schedule this time, we still went over the project amount of time by about 30 percent (we came in 3 hours over schedule).  The losses in time occurred due to the fact that none of our team is very good with html and the tools provided with Catalyst web design are cumbersome to use.  In addition, our final layout required a last minute re-design because it would not fit under the vehicle.  In order to fix this problem, we had to redesign the case shape and move some batteries.

The design concept selection process was a good learning process.  Using Pugh’s selection to weed out the poor design concepts before doing a weighted decision matrix is a great tool because it saves time.  Performing a weighted decision matrix on all 30+ of our design concepts would have taken a very long time to complete.  In the future we will be able to use the Pugh selection method to effectively reduce the number of design concepts that make it the weighted matrix stage of the design.

The design architecture was another important step for our group because we did not give much consideration to the interaction of the various elements of our design until we reached this step.  As a result our case did not fit under the vehicle well enough and had to be re-designed.  In the future, our team would like to find a way to incorporate some of the interactions into earlier phases of the design process.  This could help prevent problems with sizing, like we experienced.

In the end, after two weeks of designing a replacement battery case for the Ford Ranger EV1 our team has produced a design concept to the best of our abilities.  Our battery pack, filled with our chosen batteries, is lighter than the stock pack and is capable of storing the same amount of energy.  The largest draw back to our current design is the charging time of six to ten hours that is associated with the deep cycle Optima batteries that we selected.  However, this is the reported charging time using a standard battery charger.  It is possible that this time could be reduced by using a different charger or the power management systems present in the battery pack.  If we had more time we would like to investigate the possibilities of charging the Optima batteries faster, as it would increase the competitiveness of our product.  Conceptual pictures of our design concept can be found in the links below.

Case with cover removed

Case with cover on