Patent ID: 8724119
Filing Date: 2014-05-13
Classification: G01B,G01C,G01S,G06F

Abstract:
1. A method for locking onto and tracking a selected retroreflector target with a laser tracker, the locking onto and tracking carried out under direction of an operator, the method including steps of: providing at least one retroreflector target; providing the laser tracker, the laser tracker having a structure, a first light source, a distance meter, a first angular transducer, a second angular transducer, a position detector, a camera, a second light source, and a processor, the structure rotatable about a first axis and a second axis; the first light source configured to produce a first light beam that cooperates with the distance meter, the first angular transducer configured to measure a first angle of rotation about the first axis, the second angular transducer configured to measure a second angle of rotation about the second axis, the position detector configured to receive a reflected beam, the reflected beam being the first light beam reflected by a retroreflector target, the camera including a lens system and a photosensitive array, the second light source configured to provide a cone of light, the first light beam and the cone of light being fixed in relation to the structure, the second light source configured to cooperate with the camera, the camera having a field of view, the processor configured to operate the laser tracker; providing a tracker transceiver coupled to the laser tracker or coupled to a computer in communication with the laser tracker, the tracker transceiver including a receiver and optionally a transmitter; providing a handheld appliance having an appliance transceiver affixed to the handheld appliance, the appliance transceiver configured to wirelessly communicate with the tracker transceiver, the appliance transceiver configured to emit a wireless signal selected from the group consisting of an RF signal, a microwave signal, and an infrared signal; positioning the at least one retroreflector target within the field of view of the camera; actuating by the operator the handheld appliance and in response to the actuation sending a first wireless signal from the appliance transceiver to the tracker transceiver; in response to reception of the first wireless signal by the tracker receiver, determining a retroreflector target criterion; responding to the first wireless signal by repetitively carrying out steps in a loop including the following steps (a)-(e) and exiting the loop when an exit condition is met: (a) reflecting part of the cone of light by the at least one retroreflector target and capturing an array image on the photosensitive array; (b) determining which of the at least one retroreflector target meets the retroreflector target criterion, the determining based at least in part on the array image, the retroreflector target that meets the retroreflector target criterion referred to as the selected retroreflector target; (c) measuring a signal level with the position detector and determining, based on the signal level, whether the position detector is receiving the reflected beam; (d) establishing whether the exit condition is met, the exit condition being met if and only if the position detector receives the reflected beam and the reflected beam comes from the selected retroreflector target; (e) activating the first motor and the second motor to steer the first light beam toward the selected retroreflector target; activating the first motor and the second motor to steer the reflected beam so as to keep the reflected beam on the position detector; and measuring to the selected retroreflector target a distance with the distance meter, a third angle with the first angular transducer, and a fourth angle with the second angular transducer.