Friday, November 20, 2009

Wireless, Anyone?

The most common question I get asked when demonstrating the Sensics head-mounted displays is "Can you make them wireless?" Just like the transition from a corded phone to a cordless phone and then to a mobile phone, there are numerous reasons to wish that HMDs could be untethered: no more having to carry an 'umbilical cord' cable around, or worry about tripping over it; fewer distance limitations; greater freedom of movement.

The day of 'cutting the cord' is now here. During the first week of December, my company will demonstrate a wireless HMD at the I/ITSEC show in Orlando, and I can't wait to see the responses.

Imagine a virtual reality application to train NFL quarterbacks, who already wear helmets for a living. Let's attach a high-performance HMD to the helmet and let the quarterback move around while seeing next week's opposing defense. Maybe even add an eye tracker to make sure he is scanning the field correctly and looking at the right passing options. With tethered HMDs, this application is a problem: quarterbacks are so expensive these days, that teams might be concerned about having them trip over a cable or get tangled up. With a wireless HMD, many additional options are open.

The same is true for numerous other applications: driving simulators, maintenance trainers, infantry trainers, just to name a few.

What makes wireless video for virtual reality applications more difficult is the concern about latency and frame rate. If you are watching a movie on a TV at home, and that TV receives a wireless video signal from your PC, there is no problem if there is a consistent delay between transmit and receive. Who cares of the movie is 2 seconds delayed? But if you are wearing an HMD with a motion tracker, and the image changes based on your movements, you are on a strict latency budget. Too much latency, and you are likely to experience motion sickness. The same goes for frame rate, where interactive applications need high refresh rate.

Wireless, anyone? Come to Orlando.