Virtual Reality in Education- Understanding a range of features to select appropriate headsets
Virtual Reality (VR) has broken away from the limitations we saw in the past decades and finally transcended from ‘passing fad’ to ‘here to stay.’ The capacity for immersive interactive learning transporting the user into scenarios otherwise impossible make borderless education achievable without ever having to leave campus. Why lecture a group of students about ancient Greece when you can transport them there at the click of a button? Or gather experts from around the world together in one virtual room? Space and time are no longer barriers, and our own creativity is free to explore the possibilities. For these reasons, VR technology professionals ranked the education market second only to gaming as the highest impact VR market.
But you know all this, you’ve applied to the powers that be, and they have agreed to support you in setting up a VR teaching program. Now what?
The current market for VR headsets can quickly become overwhelming as a seemingly endless list of VR head-mounted displays (HMDs) hit the market. Based on our experience deploying VR activities to nearly 10,000 students over the last two years, here are a few tips to get you started, and a few things we wish we had known sooner.
Let’s start with some features you’ll see popping up regularly.
3DOF vs 6DOF
This describes the degrees of freedom (DOF) users experience within the VR environment and reflects the ability of the headset to track you in space. Lower end headsets and mobile phone cardboard-style setups have 3DOF tracking. These are your X, Y, and Z rotational angles, meaning they can track as you turn your head around to observe the environment. This is adequate for a seated experience, but if the user tries to move within that space the entire room will move with you, rather than you moving within it. Picture yourself sitting at a desk. You can look around and observe the room, but if you take a step forward, the desk and the rest of the room move forward as well. You may also want to bring a bucket, because this can be quite nausea-inducing.
6DOF headsets track your rotation and your position in space (rotation and translation). Now you can move around the room freely exploring within your defined play area. This is called a “room scale” experience and is not only more immersive and interactive but minimises motion sickness. Most people I have spoken to who felt sick the first time they used VR were using a mobile phone or otherwise 3DOF headset. You’ll feel that difference not only in your VR experience but unfortunately your wallet also, with 6DOF HMDs generally doubling the price of their 3DOF counterparts. As such, mobile phone ‘cardboard’ headsets are often used as an affordable way to test the VR waters but may leave a bad taste in your mouth.
Tethered vs Untethered
Until recently, portability was a major issue for VR headsets which need to be plugged into a relatively high-spec computer to run them. On top of that, the cord itself is a trip hazard and invariably gets wrapped around one of your legs as you attempt to explore your VR environment. Recent releases of untethered headsets such as the Oculus Quest which have all the required hardware built right into the HMD itself ditch the cables and enable portability.. This also eliminates the cost of the gaming computer required by tethered headsets, with the Oculus Quest carrying the same price tag as it’s tethered counterpart the Oculus Rift S. There are disadvantages, however:
1) Untethered headsets simply don’t have the power that a gaming rig can push through a tethered HMD. This is fine if you are running simple software, and that software has been adapted for the untethered version.
2) Mobile Device Management (MDM) of multiple untethered headsets is a nightmare. It’s one thing to move across 10 or 20 different computers creating accounts for each headset, setting up the software, and managing updates. It is another issue entirely with untethered headsets where you need to put each headset on and run through all these steps using an awkward virtual keyboard. In short, this simply isn’t designed for managing multiple headsets. A proper MDM would allow you to set everything up on one central machine, and simply ‘push’ it to your collection of headsets at the click of a button. Unfortunately, if you want this feature from Oculus for their Quest HMDs, you’ll need to pay triple the price for each of them through their enterprise purchasing program. But more on that later.
3) Tethered headsets allow you to see what the user is doing through the computer monitor. This is obviously not the case with self-contained untethered headsets, making it difficult for tutors to help students who may be stuck, monitor their progress, or interact. You can overcome this by pairing a tablet, but it’s not a straightforward process.
4) There’s something to be said for each student being tethered to a specific area or computer. Think excited student running at full speed across a crowded room they can’t see. In all fairness there are measures in place for this (exiting the defined play area switches the display to a pass-through camera allowing you to see your environment), but it still has a greater potential for chaos.
Inside-Out Tracking vs Sensors/Base Stations
Most HMDs come along with sensors which need to be set up to track the user’s position. The original Oculus Rift (Oculus Rift CV1) has USB sensors, and the HTC Vive and HTC Vive Pro come with two powered base stations which communicate wirelessly and need to be setup in opposite corners of the room. These are cumbersome extra bits of equipment with more wires and increased setup time. Also, if someone bumps one of the sensors weird things happen to the unexpecting student in VR.
The answer to this has been ‘inside-out tracking’ where sensors built into the headset itself ping IR light around the room to track where you and your controllers are. This tech has been built into the Oculus Quest and Oculus Rift S headsets, but other headsets such as the new Valve Index (the Ferrari of VR HMDs) have decided to stick with the base stations for tracking. Why? The inside-out tracking doesn’t quite get the job done as well. If you put your hand/controller behind your back or head, the built-in cameras can’t see it anymore and stop tracking, whereas an appropriately positioned base station would have no issue. The inside-out tracking also seems a bit more jittery, but I haven’t observed enough student hours on those HMDs to comment on whether it is more nausea-inducing.
Inside-out tracking may not be great for the hardcore VR gamers, but it should fit the bill for most education software, minimises wires and setup time, and is far less cumbersome than finding places for the sensors in a room with 20 other VR headsets.
While most VR HMDs look relatively similar (black eye box with a head strap), the hand controllers are far more variable. Mobile phone headsets generally have one button mounted on the headset itself for selecting things and 3DOF headsets such as the Oculus Go or the Lenovo Mirage come with a small remote control for navigating menus and basic interaction. These are fine for non-interactive content such as 360° video, but immersive content requires more. Midrange and high-end headsets come equipped with a pair of hand controllers for users to interact in a more immersive manner, complete with vibrating haptic feedback. The knuckle controllers of the Valve Index are capable of tracking individual finger movements and have set a new gold standard above the current offerings from Oculus and HTC.
From my experience (and I’ve yet to use the knuckle controllers), the Oculus “Touch” controllers for the Rift, Rift S, and Quest are far superior to those of the HTC Vive and Vive Pro. Touch controllers fit ergonomically in your hands and are highly intuitive - need to grab something? Just squeeze the handle. Pointing and selecting? Point and pull the trigger. The HTC Vive controllers are giant wands that feel more like ham bones than elegant VR controllers. They are unintuitive, cumbersome, easy to drop, and immersion breaking. Nothing is ever where you need it to be, so you end up spending much of your experience staring at your virtual hands trying to figure out what you are meant to press. Watch this space however, as the new Valve knuckle controllers are built to be compatible with the HTC headsets. You’ll just need to buy them separately.
Resolution and Field of View
Resolution and field of view are two factors that new HMD models continually strive to improve, and seemingly drive the price point. The Oculus Rift S and Quest are improvements over the original Rift CV1, and the Vive Pro has done the same over the Vive, but the new gold standard in the consumer market is the Valve Index. I could list a bunch of numbers here, but the bottom line is that for education purposes all that extra resolution and a wider field of view simply isn’t necessary. Leave that to the gamers and save your money for more headsets! As a colleague of mine eloquently put it: “We have thousands of students using these headsets every month, we don’t want to put them in a Ferrari, we want a Toyota Corolla- a reliable workhorse”. The Oculus Rift CV1 headsets we purchased in 2018 are still going strong despite heavy usage (by amateurs), and we’ve only lost one when a student was goofing around with their friends and faceplanted while wearing the HMD breaking one of the lenses.
Purchasing VR Headsets in Bulk
Many educators have hit repeated roadblocks trying to purchase a limited stock consumer product in bulk without sending up the ‘reseller’ flags. HTC headsets are available through multiple commercial outlets within Australia, but unfortunately Oculus (Facebook) have not made their product as accessible. The options for purchasing Oculus headsets in Australia include: 1) direct from Oculus, with a maximum of 3 headsets per purchase and a risk of having your purchasing card blocked if you try to buy too many sets of three, 2) Amazon.com.au, which now allows a maximum of 1 per customer, or 3) through Exertis (the Oculus Enterprise affiliate) which currently has a monopoly on bulk purchasing of Oculus HMDs. As such, headsets from Exertis will cost nearly three times what they would off the shelf, with your extra money buying you a more robust extended warranty and an enterprise MDM for managing your Quests. There is no ‘education package’ offered at a more reasonable rate. Current Australian retail for an Oculus Quest headset is AU$657, give or take 3 cents. Through the enterprise bulk purchasing program, they will set you back US$1000 each, or AU$1476 at today’s exchange rates. The warranty is nice, but at that price I could break every headset, replace it twice, and still come out ahead. In fact, the shiny new HMD sports car that is the Valve Index is also US$1000 complete with controllers and base stations.
Despite the massive expansion of VR into the education market, neither Facebook nor HTC seem to want to make a play for it, with HTC focussing on consumer gamers and Oculus steering towards big business and gaming cafés. Currently there are educators across this University with cash in hand waiting to buy headsets, only to hit a roadblock at point of sale. Perhaps my colleagues in the Faculty of Business and Economics could explain this reasoning to me some time. In the meantime, if you want Oculus HMDs, you’ll need to buy them in batches of three.
The Grain of Salt
In my experience, the Oculus Rift S and Oculus Quest headsets seem to be the best options for the education market. They are sturdy and reliable, simply designed, the software and drivers are relatively stable, and the inside out tracking makes setting up a VR studio far less cumbersome. The controllers for the HTC Vive are simply a deal breaker for me, and the high-end Valve Index headsets are exactly that- you don’t put an L-plater behind the wheel of a Ferrari (Bueller? Anyone?). On top of that the Oculus price point is digestible, and the Rift S and Quest headsets accommodate large-frame glasses far better than the original CV1 could. And if you’re reading this, Facebook, I’d love to be allowed to buy some.
Dr Charles Sevigny is an academic staff member and Director of Digital Learning for the School of Biomedical Sciences at the University of Melbourne. He has no formal affiliation, financial or otherwise, with any of the products or manufacturers described in this article. His opinions are his own, and do not necessarily reflect those of the University of Melbourne.