Slashdot Mirror

← Back to Stories (view on slashdot.org)

Walking In A VR Future

Posted by timothy on from the see-the-lovely-veldt dept.

neol'schmoe writes "There's a new solution to the age old problem of physical movement within a virtual world. Researchers in Japan have come up with tiles that move in concert with a user's pace and motion to allow free range of motion while literally walking in a virtual environment and never leaving a very small area in the real world."

1 of 371 comments (clear)

  1. 2d treadmills, motion sickness and Redirection by bitinglobster · · Score: 5, Informative
    This is reply to several posts. There's been a couple inquiring about other kinds of 2-d treadmills and spheres, both of which exist (see below for links to videos and papers).

    There are fundamental problems with all of these types of devices-- they 1) don't let the body handle momentum naturally and 2) don't stimulate the vestibular system in a way that is consistent with the visual or proprioceptive (the body's sense of where its limbs are) cues.

    1) Momentum: On a 2-D treadmill, the omni-directional treadmill is supposedly fast enough that it allows for running. But when you are running and then change direction quickly, your body will lean into the turn to counter its momentum. Doing this on the treadmill will make you fall over. Someone once described it as "running on a slippery ice cube".

    2) Vestibular cues: Our body can sense motion even without visuals or body movements. This is why some flight simulators have motion platforms [://www.simlabs.arc.nasa.gov/vms/motionb.html]. One post above said that the treadmill should reduce motion sickness because it provides body motions as well as visuals. But a treadmill doesn't cue the vestibular system. One theory of motion sickness is that it results from a mismatch of visual and vestibular cues. In the back seat of a car, your visual cues say you are still (relative to the inside of the car) but the vestibular system says you are moving. Similarly in a IMAX theater or while playing an FPS on a big screen, your visuals say you are moving but your vestibular system says you are still. Knowing how you are moving is critical for maintain balance and even surviving. The mismatch in visual and vestibular cues interferes with your ability to balance, and that's why dizziness results.

    Luckily, one can fool the vestibular system, much as we can fool the visual system. Techniques include "wash-out" on motion platforms, electrical stimulation, and Redirection. Wash-out is where the motion platform moves the user to simulate the virtual motion, but then sneaks her back to the center of the room at an acceleration that is below what her vestibular system can detect. The shifting tiles look like a fabulous idea, and I wonder if one could implement a form of wash-out on those tiles.

    Links

    One more thing, the problem with, as one post suggested, implementing VR in a huge wide open space (like a desert) is tracking. The computer needs to know where your head is and in which direction you are looking, very accurately and quickly, so it can draw the virtual scene from your perspective. By accurately, I mean with millimeter precision, and by quickly I mean it must update the images within tens of milliseconds of your head moving. If you focus your eyes on your figure at arms length, then rotate your head right and left, the reflex that moves your eyes to keep them locked on your finger is called the VOR (vestibular ocular reflex). It can react to head movements in 10 milliseconds.