Meaning
Precision coordinate metrology instruments use a focused light beam to measure the three-dimensional position of a retroreflective target. A laser tracker calculates distances by measuring the time of flight or phase shift of the laser beam, combined with high-resolution angular encoders to determine spatial coordinates. These devices provide sub-millimeter accuracy over distances spanning tens of meters.
Spatial Measurement
The instrument directs its beam toward a spherically mounted retroreflector held against the surface being measured. Sensors track the returned beam to calculate the target center with extreme precision.
Dynamic Tracking
In active tracking mode, internal motors continuously adjust the mirror assembly to follow the retroreflector as it moves. This capability allows the system to measure moving parts or guide robotic assembly systems in real time. The precision depends on the stability of the mount and the control loop speed of the tracking steering mechanism.
In aerospace manufacturing, these systems assemble large fuselage sections, ensuring that mating surfaces align within tight tolerances. They eliminate the need for heavy, expensive physical fixtures by providing a digital reference frame.
Environmental Calibration
Changes in air temperature and barometric pressure alter the speed of the laser through the air, requiring continuous adjustment. Operators use dedicated meteorological stations to update the tracker compensation algorithms in real time.
