When I worked on a virtual reality project that centered around patients who were visually impaired, I started to explore the idea of what a virtual reality experience could look like when you removed all visuals. This is how Sightless came to be.
With the concept that this VR game would only have haptic and auditory feedback, I started creating the framework of the game. The idea was simple. Start in the middle of a 3D space and make your way out in any direction. Initially, we hoped to make the user move faster as they got closer to the exit and convey their speed with audio feedback, but that ultimately didn't work to create the experience we wanted. Ultimately we wound up using music that got louder and more intricate as you approached your goal. This also allowed for a simpler way of explaining our goal.
Of course, we needed something to make the navigation of the space more challenging. We added obstacles, enemies that search for the player, and mines that explode on collision. Each of these had its own auditory feedback which changed in volume, speed, and pitch to give the user as much information as possible.
Limiting the scope of the project to a "virtual reality experience with no visuals and only audio" presented its own set of challenges, but it also allowed us to find simple solutions to stay true to the core idea behind the project. Currently, Sightless is available on the Oculus store.