Today’s Buzz word is VR, Virtual reality, which allows the users to experience three dimensional projected heads-up display of videos, games and movies. VR headsets transforms a 2D image into a three dimensional environment similar to the ordinary reality to be experienced by users.
Though numerous researches have already been done in this field of VR for the past couple of decades but it lacked appropriate hardware and sensors since they were very expensive and bulky. Thanks to research and development in technology, VR headsets use sensors such as optical tracking, IR sensors, gyroscopes and accelerometers to move the user’s view.
Following is a brief insight into various tracking sensors and techniques deployed in VR headsets:
Head Tracking Sensors
VR Headsets are head-based and tracks head orientation of the user. To explain it in simple words, VR senses and monitors the movement of the user and shifts the picture or the video accordingly when he moves his head in different directions from left to right or up and down. VR headsets track orientation of the user using 6 degrees of freedom (DoF) motion platform which plots different types of user’s head placement in a three dimensional axis known as x, y and z axes. Head tracking is done by using a combination of two sensing techniques i.e. accelerometer and gyroscope.
An accelerometer is a device that lets VR headset to know its orientation and position and automatically adjusts the screen in portrait or landscape mode. It not only measures placement but it calculates the linear motion or translation along some direction and thus shifts the image in accordance to the movement of the user. Six degree-of-freedom (DoF) measures this motion in three ways – User moves forward or backward, up and down, and left or right.
Gyroscope is used to monitor tilting or angular movement of the user. When accelerometer monitors the linear motion of user, gyroscope not only measures the angular motion but also regulates and controls the movement. This angular movement is measured by six degree-of-freedom (DoF) platform in following ways – User moves between X and Y axis, between X and Z axis and between Z and Y axis.
Optical Tracking Sensors and Lenses
VR headset uses two input feeds sent to LCD display placed in front of user’s eyes. VR headsets are equipped with lenses that focus and reform the picture accordingly for each eye. As a final result, a stereoscopic 3D image is created by reshaping and tilting 2D images.
Eye Tracking Sensors
Eye tracking is done using infrared sensors that monitor the movement of user’s eyes and inform VR headset about the exact direction in which the user is looking. The x-factor of this tracking is the precise detection and computation that allows the headset to respond accurately. Eye tracking is more useful in real-time 3D gaming in which entire environment is changing continuously. This tracking reduces latency and delay and subsequently improves users’ experience.
This article covers the basics of the sensors and tracking systems used in VR headsets and the basics of how they work. The next time you are watching a movie or playing a video game in VR, just spare a thought for the technology deployed to make VR possible.