1. A method for capturing motion of an object having a plurality of segments via a plurality of motion sensor modules located on the segments, each of two or more of the segments of the object having thereon at least one sensor module, each sensor module being adapted to capture 3D position data and 3D orientation data associated with its respective segment, the method comprising: collecting 3D inertial sensor data at each sensor module via at least one 3D accelerometer sensor and at least one 3D angular velocity sensor; and calculating a 3D orientation and 3D position of each segment having a sensor module by integrating the 3D angular velocity data and doubly integrating the 3D accelerometer data in time while applying a joint constraint to correct the calculated segment positions and orientations such that the segments are constrained to be linked to one another via a joint having at least one joint characteristic property, wherein applying the joint constraint is executed consistent with the at least one joint characteristic property and includes allowing a predetermined degree of laxity in one or more joints.