Today the groups had their first prototype evaluation. The roof group sketched their entire system on the white board so that Dr. Saterbak could easily see how all of the components of the system fit together. We learned the sensors originally ordered were volume dependent which would not be good for the roof (since the roof has different size trays), and so new sensors had to be ordered. A large part of prototyping is testing components to see if they actually work the way you want them too. Sometimes they don’t, and you have to start over and try something else. The group still has electronics that need to be connected to the computer, and so the last weeks of school will be devoted to synthesizing all of the components together.
Archive for March, 2011
Prototype Evaluation
Tuesday, March 22nd, 2011Prototyping
Tuesday, March 22nd, 2011The groups finally have gotten their hands dirty as they begin prototyping in the Oshman Engineering Design Kitchen (OEDK). It’s amazing how designs will succeed or fail once you starting modeling them. From drill presses to k’nex, floaties to cardboard, the room is teeming with exitement . The forearm team has a set of accelerometers they’re experimenting with. The wheelchair group is experimenting with three dimensional gears, and the surrey and roof teams are continuing to refine their prototypes as the designs are finally starting to become a reality.
pictures of prototyping, click to enlarge them:
Team Obstacles and Progress
Thursday, March 17th, 2011It has been absolutely inspirational to see the change in mood in the room now that the students are actually putting their plans into action. However, I think today many groups hit their first obstacle when they realized that the solutions might be more difficult to create than previously thought.
For example, the surrey group realized that their permanent fold out box actually caused discomfort to passengers. The team came together with the apprentice leaders and faculty to evaluate and then decide to redesign the storage space to be removable. This is only one of the several examples of how the students have actually learned the importance of a reiterative prototyping design process.
In the team meetings the groups have also began evaluating what different materials, structure, calibration requirements, and hinges the final design might require.
Testing Design Solutions
Tuesday, March 15th, 2011It’s easy to think up of a design. But how do you test it? As with all products, the three factors of speed, cost, and quality have a mutually exclusive relationship. As they say:
“You can have it fast and good, but it won’t be cheap.”
“You can have it good and cheap, but it won’t be fast.”
“You can have it fast and cheap, but it won’t be good.”
For testing design solutions, we want our products to be only good enough to prove our concept. Therefore, we strive to make our prototypes fast and cheap. But it is always a jarring step to go from the drawing board to trying to materialize some semblance of the desired product.
I enjoyed watching the wheelchair and forearm groups start their prototyping processes. The forearm group split into two subgroups to focus on two different designs: a mechanical rotation device, and an electronic accelerometer device. In the very first day, the mechanical subgroup created a cardboard prototype of one of their designs. But the prototype didn’t last long – not because it wasn’t good enough, but because half-way through they decided they wanted to change the design. In this case, it was beneficial that the team avoided the pitfall of making their first prototype “too good.” The wheelchair group also had a very important start to their prototyping process: discovering an idea didn’t work. On paper, the team was convinced that their “piston” idea would be an effective design, but once they constructed a make-shift proof of concept, it became clear that the piston design did not work in the way they thought it did. In the end, the wheelchair group went back to the drawing board to generate more ideas. For both groups, the prototyping process was very successful!