Ocean | Room-scale VR art installation for public spaces
September 30, 2016
Case: Combating VR Sickness in Immersive Installation for Public Spaces, pt. 2/2
December 21, 2017
Combating VR Sickness
in Immersive Installation for Public Spaces, pt. 1/2
User Experience Case Study
OVERVIEW
Before starting my work on Amaryllis VR in 2016, I had tried my share of Virtual Reality (VR) apps and games at various tech summits and conferences around the world. What surprised me was how little it takes to provoke symptoms of VR Sickness in users, often resulting in severe nausea and dizziness. Usually, this awful experience will completely ruin one's desire to try VR ever again.
Because I wanted Amaryllis VR to be exhibited in public spaces to all kinds of audiences, it was crucial to minimize the risk of VR Sickness. While writing my Master Thesis in Media Technology, I planned and executed several rounds of qualitative and quantitative tests with over 200 users to make the installation as robust as possible.
The result:
Only 0.01% of users experience severe VR sickness when trying Amaryllis VR : Ocean
In the rest of the article, I will explain how I achieved this.
BACKGROUND
Immersive virtual reality experiences have existed since the 60's, and so has VR Sickness:
VR SICKNESS, also called CYBERSICKNESS or SIMULATOR SICKNESS,
refers to a negative reaction to the exposure to a virtual environment.
VR Sickness occurs when the user’s eyes register that they are moving in the VR environment, while their vestibular system registers that their real body remains static. Motion sickness is the reverse phenomenon: the vestibular system senses self-motion, while the eyes do not. Both conditions can be mild to severe, resulting in headache, nausea, fatigue, disorientation, vertigo etc.
VR Sickness can be caused by:
● The VR head-mounted display (HMD)
● The system it runs on
● Poorly designed VR apps with insufficient user testing
CHOOSING THE HARDWARE & SYSTEM
My work on Amaryllis VR started before the commercial VR HMDs were launched. Having worked with early developer kits (Oculus DK1, DK2, GearVR) I noticed the difference it makes to move in the virtual environment via a controller/joystick/gamepad, and to move physically.
I was fortunate to become one of the first people in Denmark to receive a sponsored HMD from HTC/Valve called the HTC Vive Pre, on which I did the bulk of the development.
Unlike in seated or standing VR where the user remains stationary, the HTC Vive uses a room-scale system allowing for real-time 360˚ positional tracking of user movement for interacting with the virtual environment. This can in turn amplify the illusion of VR and contribute to a deeper sense of being present in the virtual environment.
And best of all: since your real body is able to walk and move in space to navigate, it helps minimize the risk of VR sickness.
Another important factor is the machine the VR system is running on. Typically, you want to be able to hit 90 frames per second(fps) when running complex, real-time, interactive VR applications on the HTC Vive. You will be rendering everything twice (once for each eye), so it's easy to see why your computer needs to be able to keep up.
If it can't, you risk getting a jittery image, which will again cause a mismatch between the user's visual and vestibular systems, resulting in VR Sickness.
For this purpose, I custom-built a desktop PC with an engineer to give me enough power and flexibility to run high-end graphics through the VR HMD without causing issues.
Unlike in seated or standing VR where the user remains stationary,
the HTC Vive uses a room-scale system with real-time 360˚ positional tracking of user movement.
DESIGNING AND TESTING THE INSTALLATION: Part 1
When the hardware was ready, the rest would be up to the design of the application itself: Creating an interactive environment specifically for VR and optimizing it to run properly via feedback and data from repeated tests with users, and several design iterations.
Amaryllis VR : Ocean underwent 5 major iterations, each with their own series of user tests and subsequent adjustments. This process took over a year, so I will only present a very condensed overview below, only including the tests relevant for VR Sickness.
To read about the features of the final installation, visit this article.
TESTING VERSION 1.0
Version 1.0 was a simple Proof of Concept with placeholder 3D objects and sound, testing the basic functionality of the VR HMD and the "feel" of moving around in a 3x3m playspace physically.
An informal preliminary test was conducted on Version 1.0 on 2 occasions at the Multisensory Experience Lab at Aalborg University in Copenhagen in Autumn 2016, with observations of user behavior and gathering general feedback about the functionality of the VR application, and to note significant, unexpected problems with the prototype. None of the 15 users reported being uncomfortable in the art installation.
TESTING VERSION 2.0
Version 2.0 was developed further to include more interactive elements and the main experience of the digital water waves in Amaryllis VR : Ocean were introduced for the first time. The water rises above the player in larger and larger waves, eventually creating the illusion of being underwater. This feature needed to be tested thoroughly on a large number of people, as an incorrect implementation could result in "seasickness", and, of course, VR Sickness.
The purpose of the tests was to gather reactions and feedback from a very large group of people and to test-run the Proof of Concept in a public setting, so I opted for informal, quantitative tests at 3 locations:
● At CopenX International VR Summit in Copenhagen where Version 2.0 was exhibited in a booth in a large hall.
● At Kulturnatten 2016 at the Ministry of Science Innovation and Higher Education
● At the Multiesensory Experience Lab at Aalborg University in Copenhagen with visitors from the Danish Film Institute.
VERSION 2.0 TEST RESULTS
Over 200 users tested the installation, including young children of 4-12 years, adults and elderly, with backgrounds ranging from VR developers, researchers and professionals from the games, film and tech industries, to first time users who had never heard of VR before.
Feedback was recorded on a mobile phone after every user test, and user behavior in VR was documented via photo and video recordings.
Only 2 out of the over 215 people
who tested Version 2.0 had to stop the installation because they felt ill.
One of them had tried a mobile VR experience with a rollercoaster ride at CopenX immediately before coming to the Amaryllis VR booth - a type of VR experience which is unfortunately frequently linked to VR Sickness due to the visual perception of acceleration while the body remains static. The cause for the other user's symptoms is unknown.
Although the settings were not controlled and the tests were informal, it was clear that the installation was robust enough to be exposed to the public and to be used by many different kinds of people. It did not produce easily observable, severe adverse effects in the vast majority of people, and the feedback was generally positive. The meditative, relaxing effects of the installation were commented on frequently.
