Developed by Valve Corporation, SteamVR™ Tracking is a complete hardware and software system that lets objects determine, in real time, where they are located within a tracked 3D space. Valve has made SteamVR™ Tracking available to companies without licensing fees.
The SteamVR™ Tracking system consists of three major blocks: Base stations that scan the room with infrared light, tracked objects, and a host PC to perform position calculations.
A tracked room has one or two base stations. Each base station outputs flashes of omni-directional infrared light along with swept planes of infrared laser light. The flash of IR light is called the Optical Sync and synchronizes all of the light to digital sensors in the room to time zero. Each sensor on a tracked object then waits to be scanned by the rotating plane of laser light. Since the sheet of laser light is rotating at a constant velocity, the angle from the base station to each light sensor can be computed by measuring the time from the sync light pulse (time zero) to the time when the plane of light hits the sensor. This sync and sweep process is repeated in the horizontal and vertical directions to provide a horizontal and vertical angle for each sensor on a tracked object.
Tracked objects can have up to 32 TS4231 Light to Digital Converters. When base station IR light is incident on a site’s photodiode, that site’s TS4231 will output a digital pulse. The TS4231 can detect very low IR light levels in high noise environments. The output each light to digital detector is sent to a Watchman function that aggregates the sync and swept laser timings from all sensor locations. These light time stamps are then sent to the PC via a wired USB connection or a wireless Bluetooth link. Tracked objects can also contain an IMU to provide a fusion of tracking information back to the PC.
The Host PC uses SteamVR™ software and the SteamVR™ API to compute the tracked object’s location. The PC software takes as input the time stamp reports for the up to 32 light-to-digital sensor inputs. These inputs are processed by a fitting engine that computes the object’s X,Y,Z location along with the rotation about the X,Y, and Z axis to deliver a real time pose of each object.
Triad Semiconductor’s TS4231 Light-to-Digital Converter (2nd Gen) is an integral part of a SteamVR™ Tracking system. You can find more details below but in summary, a tracked object, in a SteamVR™ Tracking system, has a number of Triad’s TS4231 devices located on the object to detect infrared light from position basestations located in the room.
Triad’s TS4231 Light-to-Digital Converter Integrated Circuit converts the SteamVR™ Tracking IR light into a digital signal indicating the angle of the sensor site from each tracking base station. The TS4231 is a size-optimized 9-bump WLCSP optimized for volume production and for small size and power.Find out more
The TS3633-CM1 is an excellent way to prototype SteamVR Tracking designs. The CM1 contains the TS3633 IC, a photodiode and the resistors and capacitors needed for a complete Light-to-Digital prototyping solution. The components are part of a PCB assembly with castellated pads on 100-mil centers to facilitate rapid prototyping of SteamVR Tracking solutions.Find out more
From room scale applications to console controllers and more, Triad's SteamVR hardware provides you with the tools and capability to build tomorrow's VR hardware today.