Currently available VR controllers, such as the Touch controller for the Oculus Quest 2 headset, make it possible to interact with virtual objects, but they don’t replicate how the objects feel. As a result, there’s no difference between holding a sword and holding a vase—you always feel only the familiar shape of your controller.
To address this immersion-breaking problem, a team at Microsoft Research created what they describe as a hand-mounted 360-degree shape display for virtual reality. Called X-Rings, the new input device is able to change its shape to replicate objects in virtual reality, and it can respond to user-applied touch and grasping force.
X-Rings consists of stacks of expandable plates arranged in a ring formation. When fully retracted, the rings have a diameter of 5.7 cm, and they can independently expand to 7.7 cm in just 100 ms. In practice, this means that the controller can completely change its shape in the time it takes a VR user to look from one object in virtual reality to the next.
Thanks to the integrated strap, X-Rings can be mounted to the hand so that the user’s fingers are free to move in space and only make contact with the pressure-sensitive place when the user grasps a virtual object.
X-Rings is smart enough to know how many fingers are holding it, and this information can be used to animate the user’s virtual hand accordingly. Likewise, the information about how much force the user is applying can be used to render more physically interactive objects that break when squeezed too hard.
During a user study, participants were asked to associate the shapes rendered by the X-Rings controller with objects in virtual reality. They were able to match rendered shapes with virtual objects about 80 percent of the time, which confirms that even this first-generation prototype has a huge potential to make virtual reality feel more real.