Nausea. Retching. Headaches. All-too-familiar symptoms for those unfortunate individuals who have experienced “virtual reality sickness” (and also, for those who have been to a Kenny G concert). Often compared to motion sickness, or kinetosis, the condition can arise in a user when there is a disagreement between “visually perceived” movement and the vestibular system’s sense of movement. In short, it is a major challenge for VR content developers, and also one of the reasons why several HMD companies have recommended that games run at a minimum of 90 FPS.
To deal with this problem, Sony has filed a patent application entitled “Motion Sickness Monitoring and Application of Supplemental Sound to Counteract Sickness.” The patent application was originally filed on February 5, 2015 and published today. To detect motion sickness, the application describes monitoring a user’s body motion, pupil motion, gaze, head motion, balance, or “by tracking facial expressions of the user that may indicate motion sickness (e.g., a gagging motion, sticking out the tongue, etc.).”
When motion sickness is detected, the system takes action by delivering “supplemental sound,” reducing the intensity of the game or vibrating the headset. Sony’s application claims that supplemental sound has a therapeutic effect, and in particular, describes a system to deliver “bone conduction audio” by transmitting audible or ultrasonic sound waves through a portion of a user’s skull close to the ear. These vibrations can be generated by a device incorporated into the strap of the HMD.
Sony’s application goes on to describe further embodiments for battling motion sickness including transmitting microwaves that are “safe for the inner ear,” infrared stimulation and “small electric shocks.”
The use of vestibular stimulation is a known technique to battle motion sickness in virtual reality environments (over fifteen years old), and some parties have already obtained patents for it. (See here and here.) However, it will be interesting, to say the least, to see if Sony can eventually introduce this technology into its commercial PSVR headsets. Until then, VR users will just have to keep a case of ginger ale handy.