Weekly Update #2

Published 2019/01/28


Further testing was performed on the bubblegum style dispenser this week. Jamming issues continue to affect our prototypes. A shroud and flap was designed and printed. The idea was that any ingredient that would have gotten stuck on the assembly would instead be allowed past by the flexible flap. Although this would increase the variability of our dispense cycles, it should reduce the jamming and make the system more reliable. The flap was printed out of flexible TPU material. Unfortunatly, after printing and testing, it was found that this design was still prone to jamming.












User Interface

After working on a user interface for the Pi and touchscreen front-end with TKInter and guizero, we found the packages to be to limiting for our purposes. Instead, a completely new UI system was formulated. Powered by a lightweight webserver, the Pi would display a webpage and capture information about ingredient ratios via POST requests. This was preferred because the HTML/CSS code allowed us much greater flexibility in terms of the design and functionality of the UI. To start the UI, all that is needed is to run the server python script and navigate to localhost:8080 using the Pi's web browser.













Gantry Cart

The design of the gantry cart was completed this week. The plastic cup into which the trail mix would be dispensed sits in a cart, which slides along two parallel rails between the different ingredients. The sliding action is powered by a belt and pulley system driven by a stepper motor.