Week 4 Updates

Onshape struggles

After several failed attempts to move Adwoa's Fusion 360 files to ONCAD, I decided to manually attempt to recreate a new peristatic pump inspired by her old design, as well as taking into account the new gearbox motor setup we were utilizing. The main roadblock involving moving the Fusino 360 files was the fact that there was no way to preserve sketches used in the CAD, making it much harder to get a general idea of dimensions and what tools were used to make these components. Furthermore, all of the CAD in Fusino 360 was made in 1 file, making sketches impossible to fully keep track of(since we needed to find a way to seperate them into seperate components, but that would not preserve sketches made in 1 file).

Attempt to move some STEP files into ONSHAPE

To compensate, I decided to devise a new peristatic pump design utilizing Adwoa's old design, but modifying it to match the new motor setup being used(being a 27:1 gear box attached to the same stepper motor). Although the motor not having enough torque may have been the reason why the pump did not work as intended, I was also willing to bet that the PLA structure was not strong enough either, so I decided to make a more rigid structure, as well as utilizing more infill while printing. Although, a major downside is that the new structure may not be as space efficient as the old one, but considering that it will no longer be part of the gantry, that is not an issue at all. The largest roadblock while CADing, was definitely getting used to ONSHAPE features, since I could not recognize the tools I used to know in Fusion 360. However, the main design of the pump is being preserved, and I plan on utilizing a compact structure, at the cost of utilizing more bolts on the design.

The light grey section will be directly attached to the motor, the light blue section are washers to compress the tube, the dark blue section is the main base(there will also be an additional base at the top, and the grey section is the moving portion(it slowly spins to pump the liquid in or out). The outer diameter of the tube is 3/8 '', so the washers were set accordingly

By next week, I plan on begin prototyping the pump, as well as beginning to help Advaith with full assembly of the multipurpose spin coater(since we currently are not 100% sure on whether to move the spin coater itself, or the liquid handling and heating system).