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.
