US 6,630,993 B1 · Method and optical receiver with easy setup means for use in position measurement systems

Abstract

Positions can be precisely and accurately fixed instantaneously within a three-dimensional workspace. A system of two or more transmitters each continuously sweep the workspace with two fanned laser beams which are preferably about 90 degrees apart on the rotational axis of the transmitter. A receiving instrument includes, preferably, two light detectors which detect the time at which each fanned laser beam is incident thereon. The light detectors also detect a synchronization pulse from each transmitter that is emitted once per revolution. Beams from different transmitters are differentiated by different rotational speeds and, therefore, different beam incidence cycles. Because three intersecting planes uniquely define a point in three-dimensional space, by detecting at least three of the 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.

Claims44

Dependent claims

An improved position optical detector apparatus utilizable in a measurement system for generating x-y-z data within a measurement field including a plurality of rotatably supported optical transmitters with each transmitter spaced apart from the others in the measurement field and being operatively related through a reference frame within the measurement field to define an intersection between vectors for each transmitter with each transmitter including laser means to generate two rotating substantially planar beams and a strobe means for periodically generating a strobe pulse for each transmitter at a predetermined point in the rotation of each transmitter, said apparatus comprising

a user-movable receiving instrument comprising:
at least one light detector for generating an electric signal each time one of the beams or optical strobe pulses illuminates that light detector as it is positioned within said measurement field;
memory means storing calibration data uniquely defining predetermined angular parameters of said beams;
and
means for calculating the x-y-z data corresponding to the position of said detector within said measurement field using said calibration data and said electric signals from said light detector indicative of said times at which one of the beams or optical strobe pulses illuminates that detector.

2 more elements

An improved method of implementing an optical detector apparatus utilizable in a measurement system for generating x-y-z data within a measurement field including a plurality of rotatably supported optical transmitters with each transmitter spaced apart from the others in the measurement field and being operatively related through a reference frame within the measurement field to define an intersection between vectors for each transmitter with each transmitter including laser means to generate two rotating substantially fan shaped beams and a strobe means for generating a strobe pulse for each transmitter at a predetermined point in the rotation of each transmitter, said method comprising:

storing calibration data in a memory means on said receiving instrument, said calibration data comprising predetermined angular parameters of said beams;
positioning a user-movable receiving instrument at a location for which position data will be generated;
generating an electric signal with at least one light detector on said receiving instrument at said location, said generating an electric signal being performed each time one of the fan beams or optical strobe illuminates that light detector;
and
calculating the x-y-z data corresponding to the position of said detector within said measurement field using said calibration data stored in said memory means of said receiving instrument and said electric signals from said light detector indicative of said times at which one of the fan beams or optical strobe illuminates that detector.

2 more elements

A method of quickly defining a reference frame in a position measurement system for generating x-y-z data within a measurement field including a plurality of rotatably supported optical transmitters with each transmitter spaced apart from the others in the measurement field and being operatively related through a reference frame within the measurement field to define an intersection between vectors for each transmitter with each transmitter including laser means to generate two rotating substantially fan shaped beams and a strobe means for generating a strobe pulse for each transmitter at a predetermined point in the rotation of each transmitter, said method comprising:

positioning a user-movable receiving instrument at three or more random, undefined locations within said measurement field;
recording data from light detectors on said receiving instrument at each of said locations, said light detectors generating said data in response to illumination by said fan beams and said strobe pulses from said transmitters;
calculating data about a position of said receiving instrument relative to said transmitters based on said recorded data;
calculating data about positions of said transmitters relative to each other based on said data about the position of the receiving instrument at said three or more locations relative to said transmitters;
and
establishing a coordinate system for said measurement system based on said data.

3 more elements

Dependencies are inferred from the claim text.

Method and optical receiver with easy setup means for use in position measurement systems

Life of this patent

Method and optical receiver with easy setup means for use in position measurement systems

Life of this patent

Abstract

Claims44