25 Nov Knowing the virtual reality: technologies
From 2011 until today, a great alternative of devices has emerged and many well-known companies such as Microsoft, HTC, Sony and Apple invest millions in the development of virtual devices, increasingly precise and with new forms of interaction.
This has led to the existence of a large number of devices in the market with very different capacities and a high price range, leading the consumer or companies to a conflict when making a decision as to which one should buy and which is adapted to what what are you looking for.
In this article we are going to try to differentiate them by their quality, precision, characteristics, possibilities and prices, to facilitate this decision making at the time of buying them and not to find surprises once it is in our hands.
Before entering the classification, it is necessary to be clear about several concepts:
• Full motion: Complete tracking, comes to be those devices that allow tracking (tracking) of our movements (turns, arm movements, legs, movements for a room or space).
• Absolute position: This term is related to the previous one, means that the device is capable of capturing the movement both in turns and displacements in the 3 axes XYZ.
• DOF (degree of freedom): It is related to the previous terms. It is a term that is becoming fashionable when it comes to indicating that the system works in full motion / absolute position. It is usually indicated that there are 6 DOF (3 axes for the pitch, roll, yaw turns) and 3 for displacement in XYZ.
• FOV (field of view): It comes to be the angle of vision. This concept comes in most devices that have a camera. The more angle of vision we can see more environment. The human eye is able to see up to 180⁰ although other factors that can modify this value enter.
• Resolution: The resolution is the number of pixels on the screen in horizontal by vertical (1920 x 1080 for example) It is usually given two types of resolution, depending on the device. Resolution per eye and total resolution. The first does not cease to be a division between two of the total horizontal resolution.
Classification, What can I do and what I can not do with RV systems?
When classifying the devices of virtual reality, we have taken into account a primary factor, as we interact with them. Through this classification we obtain 3 groups of devices:
• Full motion devices: Examples, HTC Vive and Oculus among others. These would allow us to move in absolute position within an experience. In the commercial field it is indicated that they are 6 DOF.
• Full motion devices with restrictions: These systems work through SLAM (vision computer) to operate in absolute position and monitor the position of the controls. We have them divided into two:
◦ Autonomous: Completely independent, they have a processor and battery in them, less powerful, but for Vall Hebrón’s proposal it would be enough.
‣ Vive Focus: Absolute position in the helmet, but not in the controls
‣ Oculus Quest: Glasses announced for 2019 (spring), absolute position of both glasses and controls.
‣ Lenovo Mirage Solo: Similar to Oculus Quest but using Google’s daydream.
‣ Cardboards: Through the use of ARCore and ARkit libraries an absolute positioning VR experience can be performed for helmets, even for the controls.
Until very recently, the autonomous systems of this group were only able to track the head, but new systems such as the Oculus Quest or the Lenovo Mirage, able to follow up, have begun to emerge. These systems have started to come out in mid-2018.
◦ Dependents: They use a desktop or laptop, increases the cost of the project by having to buy a computer and its portability. All helmets with WMR nomenclature (Windows mixed reality headset), the following are the most recommended from most to least.
• 3 axy’s devices (3 degrees of freedom or rotational freedom): These systems are limited to the interaction by rotation. Grouped by:
◦ Cardboard Systems
◦ Advanced autonomous systems:
‣ Oculus Go
‣ Google Daydream
‣ Samsung Gear VR (aunque este se considera más una cardboard avanzada).