6DoF vs. 3DoF: Understanding the difference

6DoF (Six Degrees of Freedom) and 3DoF (Three Degrees of Freedom) are terminologies commonly used in the context of virtual reality (VR) and motion tracking systems. They refer to the freedom of movement that a user or an object has within a given space. Here's a breakdown of each:

1. 6DoF (Six Degrees of Freedom):

   - In a 6DoF system, an object or a user can move freely in three-dimensional space along three axes: forward/backward (X-axis), left/right (Y-axis), and up/down (Z-axis).

   - Additionally, 6DoF systems also account for rotational movement around these three axes, allowing for rotation or orientation changes: pitch (tilting up and down), yaw (turning left and right), and roll (tilting side to side).

   - In VR headsets, 6DoF tracking means that not only can you move forward, backward, left, and right, but you can also lean, crouch, jump, and look around freely in any direction, providing a highly immersive experience.

2. 3DoF (Three Degrees of Freedom):

   - In contrast, 3DoF systems only track movement along three axes: typically, pitch (up and down), yaw (left and right), and roll (tilting side to side).

   - However, they do not track positional movement along the X, Y, and Z axes. This means users can rotate their viewpoint but cannot physically move within the virtual space.

   - Many early VR systems, such as mobile-based VR headsets like Google Cardboard or Samsung Gear VR, utilized 3DoF tracking for simplicity and cost-effectiveness. However, they offer a more limited VR experience compared to 6DoF systems.

In summary, the main difference between 6DoF and 3DoF is the level of freedom of movement they provide. 6DoF systems offer full positional and rotational tracking, allowing users to move and interact more naturally within virtual environments, while 3DoF systems typically only track rotational movements, limiting the user's freedom within the virtual space.