HISTORICAL PERSPECTIVE:

 

            In the beginning of our first semester of senior design, our class visited a local Cerebral Palsy Research Foundation (CPRF) campus to meet cerebral palsy patients in order to possibly meet some of their needs through our design projects. While most of the requests came from general CPRF residents, one particular need that was brought forward came from a business located on the campus known as BTCO.

            BTCO was effectively an income producing arm for the CPRF campus that prints physical schematics based on digital drawings from local aerospace companies. As part of BTCO’s quality assurance task, BTCO employees previously had to perform measurements of every print produced by stretching over a highly calibrated light table with a handheld microscope to measure the offset of the print from the table at one end and then comparing the offset of the print from the table at the other end. As long as the print does not deviate by more than 20 mils down the length of the table, a print passes inspection and can be shipped to the customer requesting the prints.

            While BTCO’s role within the CPRF campus seemed solid, there was one obvious issue that needed to be addressed for the company: their quality assurance process required able-bodied people to do the task rather than cerebral palsy patients. BTCO requested that one of WSU’s senior design teams propose and build a possible alternative to their current process that would allow CPRF residents to work at BTCO to do quality assurance work. BTCO claimed that a stable job would allow a resident to become self-sufficient and an income producing member of society. As our team looked around the room at the ideas of our other classmates that seemed somewhat farfetched, we became immediately excited about possibility of working on a design project that had a very real need in society. We wouldn’t have to find an application for our project; the application was right in front of us!

            When compared to the final product, our initial concept for the project looks very similar. Our project was conceived as a dual-axis robotic gantry whose frame would be mounted onto one of BTCO’s calibrated light tables. The gantry would house a high resolution digital microscope, allowing a user to conduct measurements. Our final product ended up conceptually being exactly that. The only design change that was made through the course of the project was the method that the project used to take measurements.

            Our initial prototype was conceived as a to-scale frame build from rigid electrical conduit. The housing for the camera itself would allow for two parallel aluminum bars to pass through the center of it, allowing the housing to be moved by a stepper motor that was fastened to one end of the housing with a 3” spool protruding out of a hole in the side of the housing. Using a dangling set of cables to send current to the stepper motor and communication to the digital microscope, the housing would then be capable of allowing for y-axis movement along the light table. While the camera housing is capable of moving down the length of the parallel aluminum bars, those bars were fastened to another set of short bars perpendicular to the longer bars and held two sets of wheels on each end that the bar/camera housing would use to ride along the frame. Between the two sets of wheels at one end of the bar set would be fastened a stepper motor and a junction box which would allow for the connection of the controller box to the pair of stepper motors. Literally only the dimensions and the quality of materials has changed throughout the history of our project.