Patent ID: 7285793
Filing Date: 2007-10-23
Classification: G01C,G01S

Abstract:
1. A system enabling indirect determination of a position vector (V R ) of a point position (P), the system comprising: two fixed trackers ( 10 and 10 ′) wherein the absolute positions of the trackers is known; a movable measuring device ( 20 ), the measuring device ( 20 ) including: a rigid rod ( 25 ); a pair of reflectors ( 30 and 30 ′) mounted at fixed positions on the rod ( 25 ), and a reference point (R) mounted at a further fixed position on the rod ( 25 ) and on a straight line (L) through the reflectors ( 30 and 30 ′), a first light beam from the tracker ( 10 ) acquired by reflector ( 30 ) and retro-reflected back to the tracker ( 10 ); a second light beam from the tracker ( 10 ′) acquired by the reflector ( 30 ′) and retro-reflected back to the tracker ( 10 ′); the reference point (R) positioned at the point position (P), whereby the position vector of point position (P) is determined by a vector addition operation.