Revised Mold, Figuring out Ergonomics and Designing the Nav Button

A project log for The BYTE

A hands free universal interface

charitha-jayaweeraCharitha Jayaweera 08/29/2021 at 16:370 Comments

Hello Everyone!!

While the electronics and the sensors are evolving, we need to evolve the mechanical design and define a perfect footprint that could house everything. therefore, After some research into the literature, it seemed like a shape that would retain the device in the hard palate and towards the front of the upper jaw seemed like the best choice. this would reduce choking and gaging. soft palate sometimes induce gagging and moving the tounge towards the soft palate would do that too..  Therefore, as a first revision, a shape like this seemed like a good choice. 

the wiring+ battery right now would go outside of the mouth, preferably as a collar or a earpiece.. the printed result is as follows

Its not the best print, but just to test it out, this would suffice. I kept this in the mouth for about 30min to 45 mins, with ease. you obviously have to get past the roughness of the print, but the size and placement seemed good. the notch where i'm holding the dummy is where the teeth would lock it in place, and a firm "byte" would be a click. the curved shape sits well in the roof of the mouth, and with the silicone cover, added, it would be even better, 

The Nav button would be the center extrusion. the tounge rests below this and a small motion would touch the button and an effortless motion would be required to navigate on the nav button. Another revision would be made to so that the nav button would be a bit tilted towards the tounge to make the motion even effortless. 

We are currently testing out a joystick configuration with a hall effect sensor array, therefore, a balljoint which can hold a magnet was 3D printed. 

just a simple concept of how the nav button would work, the printed ball joint seemed to work well, and for the space a silicone pad of 1mm would be used to act as a dampener for the nav button. 

As for the Mold, a new mold with some small modifications were done, to make it easier to assemble, disassemble and inject. 

added venting, moved the injection points to top, which can now be used to inject or pour. added chamfers to easier demolding. the overall end result should look like below. which ideally would only occupy 5ml of silicone

On to more exciting stuff!!

-Charitha J.