VRCAT: VR collision alarming technique for user safety

The rapid advancement of virtual reality (VR) head-mounted displays (HMDs) has made it possible to experience immersive VR at home. However, such immersion inevitably disconnects users from reality and puts their safety at risk. We suggest a VR Collision Alarming Technique (VRCAT) to overcome this problem. The fundamental idea is to use an RGB camera to identify physical obstacles around VR users and warn them about potential collisions via the HMD. We built VRCAT on a smartphone platform that is readily available to the general public to reduce learning expenses and boost accessibility to our system. To validate whether the VRCAT improves user safety and is easy to use, we ran an evaluation test and an application test. The evaluation test reveals that VRCAT can be installed by novice users in about a minute. It also demonstrates that VRCAT can estimate the 3D positions of the user and obstacles with an error of 5–7 cm every 0.09 s. The application test conducted in real-world scenarios reveals that VRCAT successfully improved user safety without compromising the user’s attention and performance on VR tasks.