Virtual reality has come a long way over the last couple of years, but for the most part its triumphs still revolve around the sense of sight. The illusion of reality falls away quickly once you toss touch and haptic feedback into the mix, as even the best controller setups grant little of the weight we associate with objects outside the digital plane.
But there's hope! At least, that is, if you have $25,000 to spend on a giant industrial robot along with a $799 virtual reality setup. A video from YouTuber Scott Devine dropped a few days ago showing someone (presumably Devine) using a Baxter robot along with an HTC Vive controller to help mimic the sensation of pushing three wooden boxes off a short ledge.
As the Vive user pushes the virtual boxes with his controllers in the video, the Baxter robot repositions a wooden panel in its arm representing the box's side to meet the user's controller at the precise spot. When the user pushes against the box in the virtual simulation, he's also pushing against the wooden panel in real life, and the robot resists the pressure just enough to recreate the resistance you'd get from pushing a real box around. (He's also noticeably being very careful not to break the fragile Vive controllers.)
Sure, it's rudimentary and expensive, and you'd probably need at least three more Baxter robots surrounding you to recreate something of the experience of a true physical space. But it's probably the right direction to head in if we ever want to make something that feels as real as the holodeck in Star Trek. For that matter, as virtual reality developer Jesse Schell predicted during last March's Game Developers Conference (slide 62 in that link), it's necessary if we want truly immersive virtual reality experiences right now.
"Putting your hands through solid objects in VR is not ideal, because it does not match your expected behavior of solid things in the real world," Schell said in a discussion of his virtual reality secret agent game I Expect You to Die. "But it helps to preserve proprioception ["your body's sense of its position and orientation"], because if you physically move your hand, but your hand in the game stops suddenly because of an object collision, you will feel a disconnect between your physical body and the virtual one."
All true, based on my own experiences in virtual reality. But with haptic feedback presenting such challenges, we'll likely just have to learn to deal with it for a while yet.