METHOD FOR ESTABLISHING A COORDINATE SYSTEM

摘要

Positions can be precisely and accurately fixed instantaneously within a thr ee- dimensional workspace. A system of two or more transmitters each continuousl y sweep the workspace with two fanned laser beams which are preferably about 9 0 degrees apart. A receiving instrument includes, preferably, two spherical light detectors which detect the time at which each fanned laser beam is incident thereon. The light detectors also detect a synchronization pulse fr om each transmitter that is emitted once per revolution. Beams from different transmitters are differentiated by different rotational speeds and, therefor e, different beam incidence cycles. Because three intersecting planes uniquely define a point in three-dimensional space, by detecting at least three of th e fan beams from the transmitters, the receiving instrument can calculate its position in the workspace. A Quick Calc setup procedure allows the use to define a desired coordinate system within the workspace.