The release of Ready Player One this weekend is a significant moment for the virtual reality industry. Ernest Cline’s bestselling science fiction adventure will achieve a Spielberg-fueled launch to new heights of popular culture fame. It describes a world where living in the virtual reality of the OASIS becomes preferable to living within a dystopian future society riddled by war and energy crises. The movie will present a VR-driven future that, like all good science fiction writing, draws on strong familiar themes recognizable by everyone today, right down to the hardware described in the film.

In the story, the OASIS can be accessed virtually free of charge by anybody that is in possession of both an OASIS visor and a pair ofhaptic gloves. The visor already looks familiar. Whilst they are smaller and lighter, with greatly improved performance over the devices of today, anybody with $800 / £500 to spare can own a similar looking headset as soon as their favorite online retailer can ship it to them. The differences between today’s technology and that described in the visor are well characterized, and there are already billions of dollars being spent in efforts to close the gap.

The other essential item for accessing the OASIS is a pair of haptic gloves. In Cline’s own words, “When you picked up objects, opened doors, or operated vehicles, the haptic gloves made you feel these nonexistent objects and surfaces as if they were really right there in front of you.” (Ready Player One, p.58). Those that can afford it can then upgrade to higher levels of immersivity, with full-body suits, harnesses, omni-treadmills and even smell towers, built to serve the user’s every touch, smell, move and desire.

These products all have various reference points within VR offerings today. The standard haptics offering within consumer VR today is a pair of controllers (HTC’s Vive Controller, Oculus Touch & Sony’s PlayStation Move, etc.) containing various sensors and inertial haptic feedback driven by one of several types of electromagnetic motor. These controllers are a simple commercial starting point, and already there are many types of additional accessories and configurations that add variety to the haptics offerings. For example, Tactical Haptics have demonstrated reconfigurable controllers which integrate shear force surface haptics as accessories on top of existing VR controllers. Both the controller designs and the haptic sensations which they enable are becoming more diverse.

The next step is to go from controllers to wearable systems such as rings or gloves, and ultimately towards apparel. It is possible to integrate similar electromagnetic motors into rings (e.g. GoTouch VR) or into gloves (e.g. Virtuix), but development increasingly tends towards the use of flexible actuators which can better match the properties of the textiles and skin with which they interact. One prominent example of this is the piezoelectric EAP (electroactive polymer) from Novasentis, who are working with many leading VR players on future product opportunities. This can be extended up to full-body apparel, where different types of actuator can be integrated throughout an entire suit (e.g. see TeslaSuit’s solution, which uses direct electrical stimulation of the muscles).

Up one step further and the systems become larger, more bespoke and more expensive. Custom haptics controllers and motion simulators have been developed to allow the user to experience the forces and sensation associated with different virtual scenarios. These range from passive systems (e.g. Icaros’ personal flight simulator) through personal and even multiplayer simulators, not unlike those within video arcades or VR theme park attractions. Omni-treadmills will become part of this, sensing the direction of motion and then literally moving the floor under the user to enable full motion in VR. We have now reached the very high end of the industry, with extremely high prices and severely limited availability to a much greater extent than anything suggested in Ready Player One.

As the number of users, sophistication of content, and total revenue in VR grows, these higher end haptics options will, in many cases, begin to see the increases in volumes and drop in prices that we can expect from any growing hardware industry. However, from a development point of view, it is important to focus on the areas in which today’s offerings are fundamentally lacking. To do this, we must break “haptics” into parts including tactile and kinaesthetic, plus other categories such as thermal sensation. The majority ofhaptic solutions, and nearly all of the consumer-ready haptics options today, are tactile. This includes any kind of vibration or surface textural change where there is no net force applied to the user. Where net force is applied, this is kinaesthetic feedback. This is typically deployed via devices such as body-anchored exoskeletons, or grounded manipulandums or robotic systems. A broad overview of the different categories of tactile and kinaesthetic devices used for haptics in VR today is shown in the image.