3 Degrees of Freedom VS 6 Degrees of Freedom
A number of virtual reality (VR) devices have rolled out within the last 5 years. And many of the newer ones are touting six degrees of freedom. If you aren’t sure what degrees of freedom means in the context of virtual reality, then keep reading…
The quick explanation
3 degrees of freedom (DoF) means you can view any direction in an experience by rotating and turning your head. But you cannot move around in the experience by moving around in real life.
6 degrees of freedom (DoF) means you can view any direction AND you can move around in virtual reality space by moving around in real life.
The longer explanation
The Degrees of Freedom (DoF) of an object represent its ability to move around in a space. In total, 3D space has six degrees of freedom. Three of them represent rotational movement (yaw, pitch and roll) and the other three represent translational movement (elevate, straff, and surge).
In virtual reality, experiences with three degrees of freedom are typically limited to the three rotational movements. Headsets that allow a 3DoF experience are typically priced lower than other headsets on the market.
A good example of a 3DoF headset is the Google Cardboard. You can look around in every direction—but there is no way for you move around the scene by moving in real life. Any translational movement has to be initiated by some other input, like tilting your head. Some current use-cases for 3DoF today are 360 tours, VR video, and basic-input games. Most 3DoF devices can be connected to the Internet, allowing for social and shared experiences.
Six degrees of freedom allows the user to look around AND move around the virtual world by moving around in reality. In order for a headset to render 6DoF experiences, it must feature orientation tracking for rotational movement and positional tracking for translational movement. Modern examples include the HTC Vive and Oculus Rift, and early 2019 will bring us the Oculus Quest.
6DoF experiences are considered to be more immersive because the input actions more closely resemble in-game movement.
Investing based on VR Degrees of Freedom?
In the long run, 6DoF experiences will probably win the favor of the market. Especially as prices drop.
3DoF experiences are a necessary stepping stone for the industry, but why have 3 when you can have 6? The main concern is the price difference, but as the difference narrows the shift towards 6DoF is inevitable.
For stationary experiences—like 360 videos—3DoF headsets are adequate for the time being. But as the industry matures we expect to see the 3DoF headset fade away.
That being said, almost every company offering a 3DoF headset also offers a 6DoF counterpart. So when considering investment opportunities, it would seem DoF isn’t the main factor you should consider. Instead consider big picture ideas. For example—what are the company’s previous successes? Or, what is their market penetration strategy?