US 11,906,729 B2 · High-precision, high-accuracy, single-hub laser scanner

Abstract

A laser scanner determines the direction and distance of one or more targets by emitting two substantially parallel beams and receiving respective return beams. Components for handling the received beams are affixed to a monolithic block to ensure fixed relative placement. The direction of the target is determined using an optical encoder to reduce the timing window for interpolation to a fraction of the time it takes for the scanner to make a full revolution. A PLL trained by recent segment timing further improves accuracy and precision. A detection algorithm adapts detection thresholds for the different signatures of return signals depending on the distance to the target. Distance calculations are also adjusted for thermal expansion of the scanner components by including a temperature-variant thermometer output signal in the distance calculation algorithm.

Claims20

Dependent claims

A scanning apparatus, comprising:

(a) a base assembly;
(b) a beam-generating assembly configured to rotate relative to the base assembly about an axis, wherein:
(i) the beam-generating assembly is configured to generate a first outward beam and a second outward beam, and
(ii) the first outward beam and the second outward beam are substantially parallel;
and
(c) a beam-detection assembly configured to rotate relative to the base assembly about the axis, wherein the beam-detection assembly is configured to detect a first reflected beam from the first outward beam, and wherein the beam-detection assembly comprises:
(i) a monolithic block,
(ii) a mirror attached to the monolithic block, and
(iii) a light sensor attached to the monolithic block.

6 more elements

Dependencies are inferred from the claim text.

High-precision, high-accuracy, single-hub laser scanner

Life of this patent

High-precision, high-accuracy, single-hub laser scanner

Life of this patent

Abstract

Claims20