April 21, 2004
First Kinkajou Gamma Design Review
We had an extremely productive design review with MIT Mechanical Engineering Prof. Woodie Flowers, Kinkajou Alpha and Beta design team member Beto Peliks, MIT LFM team members Satish Krishnan and the Gamma design team. A number of questions and suggestions resulted in the following design modifications (detailed below).
DtM is grateful to the design review participants for their time and their great ideas. We would also like to thank the staff at the MIT Lab for Energy and the Environment, for putting up with DtM as we hog yet another afternoon in the conference room.
Allen and Woodie discuss the clutches
Clockwise from L: Allen Armstrong, Satish Krishnan, Woodie Flowers, Neil Cantor, Beto Peliks, Peter Fichter
>> “Intuitive” design, this suggestion was aimed at making it clear to the user how to interface with the product. Specifically this addressed the fasteners located on both the top and bottom of the unit, making it less than intuitive as to how one accesses the inside of the unit. Action is that alternate fasteners to slotted head screws will be used, consideration was also given to using pressed in fasteners on top of the unit (no obvious methods for removal)
>> Sliding cover/focus adjustment, concern was raised over dirt causing the channel to bind as well as confusion about the dual function of the focus knob/door retainer. Action is to eliminate sliding door and replace with a simple lens cap, leaving the focus knob serving only as the focus adjustment. Search for a commercial “lens cap” has begun, we would like to tether the cap to the projector to prevent loss.
>> The value of the “hinge” feature on the front extrusion for the bottom access door was revisited. Since the assembly utilized a number of screws requiring a “tool” the value of the hinge was diminished and we agreed to eliminate the hinge and replace with two additional fasteners. This simplification eliminates the need for a custom extrusion for the front, replacement with stock material.
>> Screws in general, recommendation was to utilize fasteners which can be power driven, consideration was given to both “Torx” and “Phillips” heads, it was agreed that the universality of Philips heads tools made these an appropriate choice. Concern was raised that the threads in the aluminum heat sink/structural element, might be vulnerable to damage with multiple removal/assembly. Inserts were recommended as a possible solution, no action was taken, the expectation is that the “base” will be infrequently removed by trained individuals.
>> Film guide/focus adjustment, need to make certain that any “edges” on the metal guide are properly deburred/finished to avoid damage to the film. Initial plan is to finish these by hand, mass production would seek to utilize an automated process, eg electro polishing.
>> Ruggedness of design, questions were raised as to the ability of the projector to withstand an accidental drop. Consensus was that the design might be vulnerable to damage if dropped from table height. A number of protective methods were discussed, including padded cases, external bumpers, similar to certain flashlights, and crushable “wire frames”. Emphasis will be to beef up the design where possible, with continued thought given to “protective” features.
Posted by Timothy Prestero at April 21, 2004 12:20 PM
