During this past week, the design team continued further work on both the hardware and software side of the system. From a hardware standpoint, developments were made on new design ideas to better implement the electronics, while from a software standpoint the design team dived deeper into the GUI.
For the enclosure, the design team was able to develop a design to securely and neatly secure the PCB board into the enclosure (image below). The design uses a laser cut piece of acrylic with holes to hold down the board. This is attached at a specific height, that can be changed based on the space requirements of the electronics, using screws and stoppers that fit into threaded holes as the base of the enclosure. This allowed us to feel more intentional about the way in which we choose to put the electronics into the system and will certainly have a positive impact the durability of the product.
In addition, we ordered a machined sample of the enclosure from Polycase that is scheduled to arrive by the end of the week. We hope this gives us a better understanding of their manufacturing capabilities, and will allow the design team to experiment with early implementation of securing the PCB boards within the system. Further steps for this will include finalizing our CAD model with the EE team, in terms of final design and dimensions, as well as picking a final enclosure type and color from the website so that we can put in our order for 50 units by the start of next week.
Looking at the software side of things, the design team finalized the required functionalities of the different pages of the touchscreen and how they interact with one another. Then, the team worked towards developing initial sketches for workflow of the screens, and even began to create low-fi wireframes of the different pages. Future steps in terms of software involve getting a start on creating the GUI (in terms of designing the necessary graphics and layouts) while coordinating with the EE team on how to implement this into the touchscreen. The goal is to have a first iteration by the end of the week, so that both teams are able to get a comprehensive understanding of what is possible.
This week, the EE team focused on wiring the touchscreen together with the Arduino. Preliminary tests allowed the backlight to turn on, but graphics/text have yet to be displayed on the screen. This is likely due to differences in reference voltages between the Arduino and Teensy microcontrollers. For this reason, our EE/Software iterations will first consist of testing the Arduino with our Adafruit touchscreen, which has built in level shifters to allow for the higher voltage of the Arduino. We will use open source Arduino libraries in order to implement the interface on these touchscreens. After this has been completed, we will port the confirmed code to the Teensy, which has the appropriate voltage for other touchscreens that do not have these built in level shifters.
Once we have confirmed that this is working, we will transition to focusing almost entirely on the software aspect, with UI recommendations/inspiration from the design team.