This week we worked full time on our forearm rotation device project and occasionally we participated on a couple of workshops. We built a replica of the Rad Torquies final prototype from CAD files they developed using SolidWorks. Below is a picture of a measuring ring with wrist a attachment that we built using the Rad Torquies CAD files. The problem with the model was that the tabs were sliding in the grooves with much friction as they get pushed by rotating the wrist attachment. Our goal was to try and eliminate the friction and enhance accuracy of the device whilst maintaining the design objectives.

We built three different models of the measuring ring in trying to address the shortcomings. Basically we altered geometry and size of the rings and tabs and in two of the models we tried employing addition materials. Solidworks and 3D prinnter were our buddies over the course of the week. We developed our own CAD files and 3D printed each iteration in the prototypes. Our three prototype models were named after their geometric structure and these were concentric circles model, inner tab model and outer tab model. The inner and outer tab models are like inverted versions of each other. During testing, we observed that there was friction-less surface between tabs and respective rails because they were 3D printed using similar material as such this resulted in free motion of the tabs which was undesirable. This prompted that we should attach a thinner sheet of foam on the tabs’ sliding surface to introduce some friction and it worked pretty well. We also explored widening size of the tabs inorder to enhance stability when sliding along the rails. Below are pictures of the three models.

In addition, I undertook two workshops on laser cutting with Mikaela and post-processing with Dr Wettergreen. Mikaela taught us how to develop files for laser cutting using Adobe Illustrator and how to use the laser cutter. As part of practice I laser-cut a box out of ply wood to house an audio sensor circuit developed by my workshop partner, Lucas. He developed the circuit in a similar workshop which he and other SEED interns were attending with Helen. We wrapped up the week with post-processing workshop where Dr Wettergreen taught us procedures for fine tuning our final design before commissioning. We learnt surface smoothing and coating methods. It was a great experience and am looking forward to learn lots of stuff during the summer.