Providing Three-Dimensional Force Feedback with Thor’s Hammer

While virtual reality display technology has reached high levels of resolutions and responsiveness, usable dynamic feedback from the virtual world has remained illusive. If you were to push a button in a VR environment, for example, the best that most controllers can do is vibrate in response. There isn’t any real correlation between the visuals and the feedback, which immediately reduces a user’s immersion.

To provide force feedback that more directly mirrors what the user sees, a team at the University of Toronto has created Thor’s Hammer. The reason for the name is pretty obvious once you look at it: it’s a big block which the user holds by a perpendicularly-mounted handle. But, unlike the comic book hammer, this one is mostly empty inside and presumably pretty lightweight.

Inside of the mesh cube are six sets of motors and propellers. When feedback is called for, one or more motors whir to life and push in the appropriate direction. The hammer knows its own orientation in space, so the motors can work together to provide the correct thrust vector in response to what’s happening in the virtual environment.

To test this, the team created three virtual reality mini-games. The first lets the player dip a stick into flowing water, so that they can feel the current push against the stick. The second has players fighting to control an uncooperative sheep. The third simply provides resistance as buttons are pressed. The team reports positive results from test users, but the system is pretty loud, and you’ll likely want to use some noise-cancelling headphones if Thor’s Hammer ever hits the market.