An overview of VR locomotion techniques

Key takeaways:

• Effective VR locomotion enhances immersion and realism, making it a critical element of a quality VR experience.

• VR movement techniques include motion-based, room-scale, controller-based, and teleportation-based approaches, each with unique input methods and applications.

• Poorly implemented locomotion can lead to user discomfort, such as motion sickness, emphasizing the importance of careful design in VR applications.

Locomotion in virtual reality

Locomotion is the ability to move from one place to another in physical space. Similarly, locomotion in Virtual Reality (VR) is the ability to move from one place to another in the virtual space and is one of the pillars that makes a great VR experience. Furthermore, with the advancement of VR headsets and technology, several techniques have been developed to improve the VR experience. The following illustration provides a brief overview of how we categorize movement in VR:

Input types

The way we input movement in VR can be done using two main methods:

• Physical movements that are translated as input in the virtual space.

• Inputs using controllers that will allow movement in the virtual space.

Both these input types can be divided even further into the actual VR locomotion techniques that we use today. Let’s look at them in detail.

Motion-based

In motion-based VR experiences, we use extra sensors in addition to the VR headset. These generally include devices like the omnidirectional treadmill, which tracks physical movement and inputs it into the virtual space.

Room-scale-based

In room-scale-based VR applications, only the player’s movements in the real world are used as input in the virtual space. The applications that use this form of locomotion are hence designed around this constraint. Popular examples of VR applications that use this approach are BoxVR and Beat Saber.

Controller-based

In controller-based movement, we use controllers to input in the virtual space while the user remains stationary. These controllers can be the headset’s controllers or Bluetooth controllers in the case of mobile VR applications. However, when using this technique, we need to ensure that we do not cause vestibular mismatchVestibular mismatch is a phenomenon that occurs when the sensory information related to motion received by the brain is inconsistent or conflicting.. The triggers for vestibular mismatch can be reduced using techniques like decreasing the field of view, as this limits the amount of detail the user notices.

Teleportation-based

Compared to other approaches, this is the only non-continuous locomotion technique, which means that the user is repositioned to the targeted location instantaneously. This target location can also be selected using controllers or gaze input. The transition between the two positions can be different depending on the application. The most used form of such transitions is blinking from one place to another.

Quiz

A quick quiz to test your understanding of VR locomotion techniques.

Conclusion

Locomotion is very important as it is a key part of the UI/UX of a VR application. Effective locomotion greatly increases the realism an experience can induce. Furthermore, if locomotion is not taken seriously in an application, then it can result in sickness and nausea for the user. Hence, applications are made keeping its type of locomotion in respect, as the locomotion can very much affect how the final VR experience looks like.