Method and apparatus for directional calibration and tracking

摘要

Method and apparatus are provided to determine directional calibration parameters of an object. A method includes: disposing a tracking marker to the object, disposing the object on a calibration tool, rotating the object around its set linear axis while keeping the set linear direction unchanged, determining at least two three-dimensional rotation matrices of the tracking marker via a position tracking apparatus, and using the three-dimensional rotation matrices to determine the directional calibration parameters with the formula of two-point position relationship or rectilinear direction rotation relationship in the three-dimensional space. The action direction of the object is determined based on the determined directional calibration parameters and the current three-dimensional rotation matrix of the tracking marker. Without placing the object in a known direction or determining two points on the direction, the disclosed methods provide convenient ways to determine the directional calibration parameters, and to determine the action direction of the object.

主权项

1. A method of determining directional calibration parameters of an object to be tracked, the method comprising:
a) disposing a tracking marker over the object, disposing the object over a calibration tool, and disposing the tracking marker in a traceable region for a position tracking apparatus, wherein the position tracking apparatus is configured to receive signal from, and deduce at least direction of, the tracking marker in the three-dimensional space; b) rotating the object around a set straight line as an axis, while keeping the direction of the straight line unchanged in a three-dimensional space; c) during rotation of the object, obtaining at least two groups of rotation status parameters of the tracking marker in at least two different rotation positions, and based on the at least two groups of rotation status parameters, determining at least two three-dimensional rotation matrices for computing the directional calibration parameters; d) with the three-dimensional rotation matrices determined from step c), solving simultaneous equations to compute the directional calibration parameters for a set direction of the object.