“We Dwell Bellow” Custom HTC Vive Hardware

Last month our VR label OONI debuted We Dwell Below, a new VR experience developed for the Abandon Normal Devices Festival in the UK. The mutli-player VR experience included one particularly unique aspect: the ability to “eat” elements of various scenes. In order to detect a user “chewing”, we developed custom electronic sensor hardware that was integrated into the HTC Vive headset itself.

We Dwell Below at AND Festival 2017. We also designed costumes for participants to wear during the experience.

For the “chewing” detection capability, we designed a chin strap which would apply pressure to an FSR sensor connected to a Teensy micro-controller. The Teensy MCU reports real-time sensor data to the Unity application over USB, allowing the app to react to the opening and closing of the user’s jaw.

The circuit itself is rather simple: a pull-down resistor on the analog line of the FSR sensor, and 2 white LEDs for visual feedback as well as an added aesthetic to the device.

Circuit schematic for the We Dwell Below VR Sensor Add-on

We took advantage of an under-utilized feature of the Vive headset: an auxiliary USB port located in the connection panel of the HMD itself. This female USB-A port not only provides the standard 5V, but also provides a Serial port accessible by the Unity application. This is quite clever because it saves us from running a USB cable over the already cumbersome length of the Vive HMD.

We Dwell Below is a co-production between Ooni and Abandon Normal Devices, commissioned by Abandon Normal Devices and supported by public funding from Arts Council England. It premiered at the Abandon Normal Devices Festival in Castleton, UK on 21–24 September 2017.