Most VR is a pretty voyeuristic experience. For the most part we get to watch, but not really take part in what’s going on around us in the virtual world. Stick a controller in our hands and things are a little more interactive. Give us hand-tracking motion controls and we really feel like we’re therefore real. But when you reach out to grab or touch something in the VR world you end up grasping at thin air because, of course, there’s nothing to feel.
Haptic technology exists to simulate touch and give the user the perception of touching an object that only exists in the virtual world. This is useful for a lot of practical reasons, not just to make things more realistic. Have you ever tried to walk or handle objects with a numb limb? You have no idea how hard you’re gripping something or whether you’re stepping on something stable or not. Now let’s say you had to learn surgery or how to operate a machine in VR. A large part of that learning has to do with “muscle memory” or the direct tactile learning the we do when we practice something physically. A good haptic system can simulate the feeling of holding an instrument in your hand or a car’s steering wheel.
Of course, it also helps with immersion and realism, which are by themselves good enough reasons to want haptics as a mainstream part of VR technology.
Have We Met?
Oddly enough, haptics technology is the one VR technology most of us are actually familiar with already. It’s been in a lot of non-VR products over the years. For example, if you have a modern top-tier smartphone with a touch screen you’ll know that the phone uses a precise vibration element to simulate button clicks when it has no buttons at all.
Giving us tactile feedback makes using technology a lot more natural. After all, it provides a whole new channel of communication. If you’ve ever used Google Maps to navigate as a pedestrian then you’ll know that it uses vibrations to tell you whether to turn left or right. This means you don’t have to walk around the city with your smartphone out like a big fat target for muggers.
Haptics have also made digital media like video games a little more immersive. When the Playstation 1 introduced rumble with the first DualShock controller, it brought a whole new dimension to what were rather primitive games by today’s standards. When your in-game car ran over rough terrain the controller would rumble. When you fired your machine gun in a shooter, you could feel the recoil – albeit in a safe and gentle way.
While it doesn’t get that much attention, modern gaming consoles have incredibly advanced haptic feedback. Comparing the detail in the rumble of those early controllers of force feedback PC hardware peripherals with what we have today is like night and day. New consoles such as the Nintendo Switch have haptic feedback so advanced that it can simulate the feeling of jiggling pudding or marbles “rolling” around “inside” the controller.
Made for the Virtual
While these haptic features definitely enhance the experience of using a phone or a video game on a console, the feature is hardly something you could call essential. There are plenty of people who turn haptic feedback off with these devices, but when it comes to VR, not having haptic feedback leaves a major hole in the entire experience. This is why haptics have been part of the plan for VR from the very beginning. Let’s look at some of the ways that engineers have been able to simulate touch and force.
When you push against a real object the laws of physics says they have to push back. For every action, there’s an equal and opposite reaction, as Newton discovered centuries ago. When you push against a wall in VR, in reality you’re just pushing against air. In some ways it’s like you’re a ghost in the virtual world. It’s not real to you and you are not real to it. In order to make it feel real, something has to push back on its behalf; today the only real way to do this is by having a machine apply force to your body.
This is the first type of haptics I’d like to talk about. Basically it involves a robotic system that’s designed to fit onto your body and work against you. Think of it as a reverse-Iron Man suit. An exoskeleton that can work against whatever you try to do or fails to work against you when the time is right.
A Shocking Experience
Remember those products that use electric shocks to stimulate your muscles so that you don’t have to exercise? Well, sorry to break it to you, but those don’t actually replace real exercise. Yet the same basic technology can be used for haptic feedback. It’s still experimental, but scientists at the Hasso Plattner institute in Germany (of course) have been able to replicate both the shape and weight of an object in VR by sending signals to muscles directly.
One of the big advantages of this approach is that there’s no bulky mechanical or pneumatic gear to wear. Your own muscles become the motors that drive the haptic experience. Personally, I can’t wait for this technology to become a consumer product, but then again the public might not like the idea of mild electric shocks in their VR experience.
Full of Hot Air
A common type of feedback alternative to mechanical devices are air bladders. For example, a glove might have several small bladders that can be rapidly inflated and deflated. In this system, the glove can simulate the feeling of holding an object such as a ball or steering wheel. This technology has gotten quite good over the years, but it’s still a little awkward and not as precise as other options.
The Future of Haptics
The future of haptics might in fact involve none of these technologies at all. Ironically, it may not act on your physical body. The key may lie in a type of technology called a “brain computer interface”. Basically, instead of sending signals to your brain through your skin, nerves, and other physical sense organs, we send information directly to the brain. One day you could have a brain implant, or perhaps some external machine, that intercepts the nerve signals and then produces new ones, making you feel almost anything.
It’s not so weird when you think about it. Your own brain naturally does something similar when you sleep. When you’re dreaming you’re essentially in your own sort of natural VR. You may be running flat out in your dream, but that doesn’t mean that your own body, lying in bed, is also running at full tilt. The brain cuts off the nerve signals that would have gone to your limbs and keeps them in a loop while you sleep.
Sometimes this block is imperfect, so your legs might move a little bit or some other weaker form of the dream movement makes it through to the real world. The opposite can also happen. Sometimes as you wake up from the dream state your body doesn’t release the blocks on your movement at the right time. This is what happens in the case of sleep paralysis, a somewhat scary situation where you wake up but can’t move your body. I know plenty of people reading this have experienced sleep paralysis.
We already have technology that can modulate nerve cells using magnetism. A technique known as transcranial magnetic stimulation is used to temporarily disable brain cells to help us understand brain dysfunction. Maybe one day similar technology can not only switch nerves off, but send virtual information into them.