Researchers from Human Computer Interaction lab at the Hasso Plattner Institute in Potsdam, Germany, developed a new project, where to explore how to add haptics to walls and other heavy objects in virtual reality. The main idea is to prevent the user’s hands from penetrating virtual objects by means of electrical muscle stimulation (EMS). The figure below shows an example. As the shown user lifts a virtual cube, our system lets the user feel the weight and resistance of the cube. The heavier the cube and the harder the user presses the cube, the stronger a counterforce the system generates. The figure below illustrates how system implements the physicality of the cube, i.e., by actuating the user’s opposing muscles with EMS.
In fact, when the user grabs the virtual cube, the user expects the cube’s weight to create tension in the user’s biceps and the cube’s stiffness to create a tension in the user’s pectoralis. In order to create this sensation, the system actuates the respective opposition muscles. In order to put a load onto the user’s biceps, it actuates the triceps and in order to put a load onto the user’s pectoralis, it actuates the user’s shoulder muscle. This creates the desired tension in biceps and pectoralis, thereby creating the desired experience.
The system stimulates up to four different muscle groups. Through combinations of these muscle groups, the system simulates a range of effects. When pushing a button mounted to a vertical surface, for example, the system actuates biceps and wrist. In the Example Widgets section of publication at CHI’17, will see details how this allows the system to simulate a wide range of objects, including walls, shelves, buttons, projectiles, etc.
The system can be worn in a small backpack. The backpack contains a medical grade 8‑channel muscle stimulator, which we control via USB from within our VR simulators. The system is used in the context of a typical VR system consisting of a head-worn display (using a Samsung/Oculus GearVR) and a motion capture system.
For more info about project, please visit https://hpi.de/baudisch/projects/vr-walls.html