Though haptic force-feedback has seen some use in virtual reality (VR) with devices such as haptic controller gloves, there is yet to be much integration of haptics into augmented reality (AR) or mixed reality (MR). That all be about to change thanks to a new prototype device for Microsoft HoloLens.
Hasso Plattner Institut (HPI) is developing a mobile system to improve the immersion of AR and MR experiences by integrated force feedback using electrical muscle stimulation, or EMS.
EMS has been used in medical contexts for therapeutic use for quite some time, and the team at HPI chose EMS as its force feedback method since it allows physical forces to be acted on the body, but keeps the hands free from extra devices.
The HPI team note that one of the challenges of creating a haptic system for MR and AR is that users will encounter physical objects in addition to virtual ones, so keeping the hands free of encumbrances is important. As such, the typical haptic systems which involve exoskeleton gloves and in-built motors tend to be quite bulky, which the team decided was unsuitable for an MR set-up.
The approach taken by the HPI team involves stimulating force-feedback using self-adhesive EMS electrodes, similar to the ones used in commercial TENS muscle therapy devices. This allows the HPI system to be small, light and portable and to easily fit under the user’s clothing, with no need for adjustment straps or multiple size variants.
The system is in prototype phase, being paired with a Microsoft HoloLens headset. A number of MR apps and scenarios are being tested, such as a simple catapult game, or a moving marble app that uses a physical tray as a prop, rendering the shifts in gravity as the virtual marble moves by actuating the user’s arms towards the heavier side.
The project is open-source, with the assets available for perusal on GitHub. A video demonstration of the project is available to view below. VRFocus will continue to bring you news on the HPI project and other new and upcoming immersive technology projects.