And now, a story of failure not the fault of the 3D printer. The previous project allowed my Nexus 5X phone to sit correctly in the Utopia 360 VR viewer. This project addresses the next problem: the need to tap the screen during use of the VR app.
The first step is to buy a “touchscreen stylus” available everywhere (marginally useful) electronics accessories are sold. I planned to design and 3D print a small contraption to put inside the headset to hold the stylus and press it against the screen on demand.
The holder part was a tube whose dimension needed to match the stylus so it can be held tightly. That took a few trials and errors. Then the problem is how to mount it and how to control it from outside the viewer. After a failed design using rotation motion and a small spring, I switched to a linear motion design with a rubber band.
The rubber band’s role is to keep the stylus at a particular location. Then I can use a length of string to pull the stylus away from that position, against the screen. Once tension is released from the string, the rubber band will pull the stylus back to standby position.
Mechanically, this screen tapper contraption worked – I could pull the screen and the stylus would push against the screen, but nothing happened!
After a bit of research, I learned that the stylus is not enough to trigger the capacitive touchscreen by itself. To trigger the necessary capacitance effects, the stylus needed to be in electrical contact with a person’s finger, so it only works when held by hand, not when held by a plastic rubber band widget.
At this point I got frustrated with the whole thing and didn’t feel like designing a new V3 tapper mechanism. I went even lower tech – drill a hole so I can hold the stylus by hand and tap the screen from outside the viewer.
Sometimes, the solution doesn’t involve a 3D printer.