DE202004008110U1 - Autonomous, self-referencing head tracking module - Google Patents

Abstract

An autonomous, self-referencing head tracking module, characterized in that the accumulator and transmitter unit allow wireless operation and an integrated bracket or clip enables comfortable wearing on or behind an ear.

Description

A motion tracker is a technical device to capture the changeable spatial Position and rotation of objects. Head tracking is general Term used for the detection of head movements, and as a head tracker the meant for equipment or systems. Register depending on the version and application Head tracker from two rotational movements of the head up to six degrees of freedom [DOF].

Head trackers can be found among others application

• - as Computer mouse replacement for motorized People,
• - in Virtual Reality [VR] applications where otherwise wearing a VR glasses [Head mounted device, HMD] can lead to so-called 'cyber sickness', a feeling of dizziness or malaise due to the fact that the pretended virtual Environment remains rigid despite movement of the head.

Head trackers may also be suitable

• - as supplementary User interface so that instead of frequent switching between mouse and keyboard hands can largely remain on the keyboard,
• - at Completely mouse and keyboard-free operation of a computer using voice control,
• - for surround sound applications.

For one over Wide acceptance of head trackers for special applications As a user interface to computers, it is necessary that this

• - under diverse Ambient conditions immune to interference function,
• - the natural Do not restrict freedom of movement,
• - comfortable and inconspicuous can be worn
• - are inexpensive.

These requirements are met with the listed in protection claim 1 Features met.

For the above-mentioned fields of application are autonomous self-referencing Motion tracker [self tracking, sourceless motion tracking] especially suitable because they do not need any explicit external reference sources, so are not subject to local restrictions due to technology, a relatively high resolution enable and are insensitive to external interference. Can be cited as disadvantageous be that they are not absolute but only differential Allow positioning and are subject to strong drift in some cases. Typically, acceleration (inertial), inclination, Magnetic field (magnetometer) and / or gyroscope sensors for use (e.g. DE10192575 T1).

Autonomous motion trackers face:

• - External sensors (not subject to movement), which position and Alignment of reference sources attached to the moving object are. Optical, acoustic, or electromagnetic sensors.
• - Movement following Sensors (attached to the moving object) which determine the position Capture fixed external reference points. This essentially corresponds the above technique.
• - Mechanical Systems in which angle sensors measure the deflection of lever arms, which are attached to the moving object.
• - video-based systems, in which image processing evaluates the data from an external video camera.

Current headtrackers are either integrated into a helmet, or require wearing a headband, a hat etc. Other are optimized to be put on VR glasses, and are therefore without carrier medium not usable; these are also wired and thus restrict Freedom of movement and comfort.

The invention on which protection claim 1 is based enables the comfortable wearing of an autonomous self-referencing head tracker ( 1 ) on or behind an ear with freedom of movement that is only limited by the maximum signal transmission distance.

For this purpose, the actual tracking unit is expanded by a wireless transmitter and the device ( 1 ) operated with accumulators). The sensors allow at least the detection of the two rotational degrees of freedom pitch [ 11 ) and yaw [yaw] ( 12 ), but it makes sense to detect the roll movement [roll] ( 13 ) supplements and in the most universal case can also translatory movements ( 14 ) of the head. A receiving module, not specified here, converts the incoming data stream to position and direction data for a VR application, or to motion-equivalent mouse protocol data for conventional 2D applications.

Embodiments of the invention are in the drawings 2 to 8th shown. It shows: 2 the possible structure of the device ( 1 ) exemplary for 3 DOF consisting of: inertial sensor (s) and / or magnetic field sensor ( 21 . 22 ), Electronics for a radio transmitter in the ISM band for 433.92Mhz ( 23 ), On / off switch ( 24 ), Accumulators ( 25 ), Antenna (here conductor loop) ( 26 ), Charging cable socket ( 27 )

3 - 8th different carrying options and holding devices such as: wearing on the ear ( 4 ) or behind the ear ( 3 ) with an open ( 2 ) or closed ear hook ( 4 ), an ear clip ( 5 ) and the attachment to a temple ( 6 ) or on a headset (headset) ( 7 ). The holding devices can be design-specific or can be converted.

Claims (5)

An autonomous, self-referencing head tracking module, characterized in that the accumulator and transmitter unit allow wireless operation and an integrated bracket or clip enables comfortable wearing on or behind an ear. A head tracking module according to claim 1, characterized in that detects at least two, maximum six degrees of freedom of movement become. A head tracking module according to the preceding claims characterized that except natural Reference values (gravitation, Earth's magnetic field) no external reference sources are required. A head tracking module according to the preceding claims characterized that optional bracket or clip for attachment provided on an eyeglass frame or a headset are. A head tracking module according to claim 3 or 4 thereby characterized in that by folding the handle in and out Module is switched on or off.