Haptic feedback controllers for virtual reality applications have moved beyond handhelds, with some favoring glove-based interfaces, while others prefer a unique approach that focuses on a single element, such as providing a sense of touch and interaction using a single finger. At least that’s the idea behind the RollingStone — a controller that ‘enhances the experience of active finger exploration’ within a VR environment.
Designed by researchers from the National Taiwan University and National Chiao Tung University, the RollingStone using a single slip tactile pixel that produces the sensations of sliding your finger across different surfaces and textures in VR.
For example, when you move the RollingStone on a virtual surface, the controller uses a technique known as backward slip feedback, which feels as though you’re touching a particular surface. Varying the speed of the slip changes produces different texture sensations, like moving your finger over sandpaper or the spine of a book.
The RollingStone features a 3D-printed ball-based slip display, as well as an HTC Vive tracker and handle. The slip display was printed in two layers, with a metal gear motor sandwiched between both, which are used to actuate the ball, allowing it to rotate along both vertical and planar directions. Adjusting the speed of those motors produces the textured sensations when touching VR objects and surfaces, essentially tricking the mind to feel things that are not there.
To test their controller, the researchers designed several games that take advantage of the slip tactile pixel design — including Decorating a Room (which lets users assign different colors and textures to furniture in a virtual bedroom), Escaping from the Room (where players need to find and press the correct book to escape from a locked room), and Ninja Survival (throwing darts at advancing virtual assailants).