# US 10,480,928 B2 · Parallax-based determination of dimension(s) related to an object > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,480,928 B2 - Document ID: US10480928B2 - Status: Granted - Kind: B2 - Application number: 15/244,831 - Filed: 2016-08-23 - Published: 2018-03-01 - Granted: 2019-11-19 - Earliest claimed: 2016-08-23 - Assignees: Datalogic USA, Inc. - Applicants: Datalogic Automation, Inc. - Inventors: Andrew Hatstat - Web page: https://patentgrep.com/patent/US10480928B2 ## CPC - G01B 11/00: Measuring arrangements characterised by the use of optical techniques - G01B 11/02: for measuring length, width or thickness (G01B11/08 takes precedence) - G01B 11/24: for measuring contours or curvatures - G01B 11/25: by projecting a pattern, e.g. {one or more lines,} moiré fringes on the object (G01B11/255 takes precedence {; image analysis for depth or shape recovery G06T7/50}) - G01B 11/2513: {with several lines being projected in more than one direction, e.g. grids, patterns} - G01C 3/08: Use of electric radiation detectors - G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) ## Abstract First and second reflective portions are angled (e.g., included angle of approximately 178 degrees) with respect to one another to produce a parallax image of a structured light pattern (e.g., linear pattern) projected onto a surface of an object to determine at least one dimension (e.g., range, height, width) associated with the object. The reflections may be detected by a light sensor (e.g., a single linear image sensor) as dual “differential” parallax images of the structured light pattern, which advantageously inherently causes errors to cancel out. ## Claims ### Claim 1 A system, comprising: a light source operable to emit light outward into an environment; a first reflective surface and a second reflective surface, the first and the second reflective surfaces positioned with respect to the light source to concurrently receive light returned from an object in the environment as a structured light pattern, the second reflective surface oriented at a non-zero angle with respect to the first reflective surface; a light sensor positioned to concurrently detect, in parallax, light reflected from the object in the environment via both the first and the second reflective surfaces, respectively as a first instance of the structured light pattern reflected from the first reflective surface and a second instance of the structured light pattern reflected from the second reflective surface; and at least one processor communicatively coupled to the light sensor, and which in operation correlates a relative position of the first and the second instances of the structured light pattern detected by the light sensor and determines at least one dimension related to the object based at least in part on the correlation of the relative positions of the first and the second instances of the structured light pattern detected by the light sensor, wherein to correlate a relative position of the first and the second instances of the structured light pattern detected by the light sensor, the at least one processor: for the first instance of the structured light pattern, determines at each of a plurality of positions along the first instance of the structured light pattern a respective centroid for the first instance of the structured light pattern at the respective position; and for the second instance of the structured light pattern, determines at each of a plurality of positions along the second instance of the structured light pattern a respective centroid for the second instance of the structured light pattern at the respective position. ### Claim 2 (depends on 1) The system of claim 1 wherein the non-zero angle between the first and the second reflective surfaces is an obtuse angle that is less than 180 degrees. ### Claim 3 (depends on 1) The system of claim 1 wherein the first reflective surface is a planar surface that has a respective inner edge and the second reflective surface is a planar surface that has a respective inner edge, the second reflective surface spaced from the first reflective surface with a gap between the respective inner edges of the first and the second reflective surfaces, and the light passes through the gap outward into the environment. ### Claim 4 (depends on 1) The system of claim 1 wherein the first reflective surface is a portion of a first mirror and the second reflective surface is a portion of a second mirror, the second mirror separate and distinct from the first mirror. ### Claim 5 (depends on 1) The system of claim 1 wherein the first reflective surface is a first portion of a mirror and the second reflective surface is a second portion of the mirror. ### Claim 6 (depends on 1) The system of claim 1 wherein the light sensor is a single two-dimensional light sensor, and further comprising: at least one mirror positioned with respect to the light source and operable to at least one of rotate or pivot to produce the structured light pattern. ### Claim 7 (depends on 1) The system of claim 1 wherein the light sensor is a two-dimensional image sensor, and further comprising: a conveyor that carries the object past a field of view of the two-dimensional image sensor via the first and the second reflective surfaces. ### Claim 8 (depends on 1) The system of claim 1 wherein the at least one dimension related to the object determined by the at least one processor includes a distance to a surface of the object. ### Claim 9 (depends on 8) The system of claim 8 wherein the at least one dimension related to the object determined by the at least one processor includes a height of the object. ### Claim 10 (depends on 9) The system of claim 9 wherein the at least one dimension related to the object determined by the at least one processor includes at least one of a width of the object or a length of the object. ### Claim 11 (depends on 1) The system of claim 1 wherein to determine at least one dimension related to the object based at least in part on the correlation of the relative positions of the first and the second instances of the structured light pattern, the at least one processor: determines a range to the object based on the determined centroids along the first and the second instances of the structured light pattern. ### Claim 12 (depends on 11) The system of claim 11 wherein the at least one processor determines the range to the object based at least in part on the determined centroids for each of the positions along the first and the second instances of the structured light pattern. ### Claim 13 (depends on 11) The system of claim 11 wherein the at least one processor determines the range to the object further based on a set of calibration information. ### Claim 14 (depends on 11) The system of claim 11 wherein the at least one processor averages the results of the determined range to the object based on the determined centroids for each of the positions along the first and the second instances of the structured light pattern. ### Claim 15 (depends on 11) The system of claim 11 wherein to determine at least one dimension related to the object based at least in part on the correlation of the relative positions of the first and the second instances of the structured light pattern, the at least one processor: determines a height of the object based on the determined range and a distance to a surface on which the object is supported. ### Claim 16 (depends on 11) The system of claim 11 wherein to determine at least one dimension related to the object based at least in part on the correlation of the relative positions of the first and the second instances of the structured light pattern, the at least one processor: determines a width of the object based on the determined centroids. ### Claim 17 (depends on 16) The system of claim 16 wherein the at least one processor determines a width of the object based at least in part on the determined centroids for each of the positions along the first and the second instances of the structured light pattern. ### Claim 18 (depends on 17) The system of claim 17 wherein the at least one processor averages the results of the determined width of the object based on the determined centroids for each of the positions along the first and the second instances of the structured light pattern. ### Claim 19 (depends on 16) The system of claim 16 wherein the at least one processor determines the width of the object further based on a set of calibration information. ### Claim 20 (depends on 16) The system of claim 16 wherein the light source is a laser, the structure light is a linear pattern of laser light, and further comprising: a lens and a bandpass filter in an optical path of the light sensor. ### Claim 21 (depends on 1) The system of claim 1, wherein the structured light pattern includes at least one of a laser line, a scan line, a line of dots, a line of spots, a laser stripe, or multiple lines. ### Claim 22 A method, comprising: emitting a light beam by a light source; reflecting light returned from an object in an environment by a first reflective surface; concurrently reflecting the light returned from the object in the environment by a second reflective surface, the second reflective surface oriented at a non-zero angle with respect to the first reflective surface; detecting by a light sensor the light reflected from the object in the environment via both the first and the second reflective surfaces in parallax, respectively as a first instance of a structured light pattern reflected from the first reflective surface and a second instance of the structured light pattern reflected from the second reflective surface; and determining by at least one processor communicatively coupled to the light sensor, at least one dimension related to the object based at least in part on a correlation of a relative position of the first and the second instances of the structure light pattern detected by the light sensor including: for the first instance of the structured light pattern, determining at each of a plurality of positions along the first instance of the structured light pattern a respective centroid for the first instance of the structured light pattern at the respective position; and for the second instance of the laser line, determining at each of a plurality of positions along the second instance of the structured light pattern a respective centroid for the second instance of the structured light pattern at the respective position. ### Claim 23 (depends on 22) The method of claim 22 wherein emitting a light beam by a light source, outward into an environment includes passing the light beam through a gap between respective inner edges of the first and the second reflective surfaces. ### Claim 24 (depends on 22) The method of claim 22, further comprising: rotating or pivoting at least one mirror to reflect light emitted by the light source as the linear pattern. ### Claim 25 (depends on 22) The method of claim 22 wherein the light sensor is a two-dimensional image sensor, and further comprising: transporting the object by a conveyor past a field of view of the two-dimensional image sensor. ### Claim 26 (depends on 22) The method of claim 22 wherein determining at least one dimension related to the object based at least in part on a correlation of a relative position of the first and the second instances of the structured light pattern detected by the light sensor includes determining a distance to a portion of the object by the at least one processor. ### Claim 27 (depends on 26) The method of claim 26 wherein determining at least one dimension related to the object based at least in part on a correlation of a relative position of the first and the second instances of the structured light pattern detected by the light sensor includes determining a height of the object by the at least one processor. ### Claim 28 (depends on 27) The method of claim 27 wherein determining at least one dimension related to the object based at least in part on a correlation of a relative position of the first and the second instances of the structured light pattern detected by the light sensor includes determining at least one of a width of the object or a length of the object by the at least one processor. ### Claim 29 (depends on 22) The method of claim 22 wherein determining at least one dimension related to the object based at least in part on the correlation of the relative positions of the first and the second instances of the structured light pattern, includes: determining a range to the object based on the determined centroids along the first and the second instances of the structured light pattern. ### Claim 30 (depends on 29) The method of claim 29 wherein determining the range to the object based at least in part on the determined centroids includes determining the range for each of the positions along the first and the second instances of the structured light pattern. ### Claim 31 (depends on 29) The method of claim 29 wherein determining the range to the object based at least in part on the determined centroids includes determining the range to the object further based on a set of calibration information. ### Claim 32 (depends on 29) The method of claim 29 wherein determining at least one dimension related to the object based at least in part on a correlation of a relative position of the first and the second instances of the structured light pattern detected by the light sensor further includes averaging the results of the determined range to the object based on the determined centroids for each of the positions along the first and the second instances of the structured light pattern. ### Claim 33 (depends on 29) The method of claim 29 wherein determining at least one dimension related to the object based at least in part on the correlation of the relative positions of the first and the second instances of the structured light pattern, includes: determining a height of the object based on the determined range and a distance to a surface on which the object is supported. ### Claim 34 (depends on 33) The method of claim 33 wherein determining at least one dimension related to the object based at least in part on the correlation of the relative positions of the first and the second instances of the structured light pattern, includes: determining at least one of a width of the object or a length of the object based on the determined centroids. ### Claim 35 (depends on 34) The method of claim 34 wherein determining a width of the object based at least in part on the determined centroids includes, for each of the positions along the first and the second instances of the structured light pattern, determining the width of the object based at least in part on respective ones of the determined centroids. ### Claim 36 (depends on 35) The method of claim 35 wherein determining at least one dimension related to the object based at least in part on a correlation of a relative position of the first and the second instances of the structured light pattern detected by the light sensor further includes averaging the results of the determined width of the object based on the determined centroids for each of the positions along the first and the second instances of the structured light pattern. ### Claim 37 (depends on 34) The method of claim 34 wherein determining a width of the object based at least in part on the determined centroids includes determining the width of the object further based on a set of calibration information. ### Claim 38 A system, comprising: a light source operable to emit light outward into an environment; a first reflective surface and a second reflective surface oriented relative to each other at a non-zero angle, and positioned with respect to the light source to concurrently receive light returned from an object in the environment as a structured light pattern; a light sensor positioned to concurrently detect, in parallax, light reflected from the object in the environment via both the first reflective surface and the second reflective surface, respectively as a first instance of the structured light pattern reflected from the first reflective surface and a second instance of the structured light pattern reflected from the second reflective surface; and at least one processor communicatively coupled to the light sensor, and configured to: correlate a relative position of the first instance of the structured light pattern and the second instance of the structured light pattern by determining at each of a plurality of positions along the first instance of the structured light pattern a respective centroid for the first instance of the structured light pattern at the respective position, and determining at each of a plurality of positions along the second instance of the structured light pattern a respective centroid for the second instance of the structured light pattern at the respective position; and determine at least one dimension related to the object based at least in part on the correlation of the relative positions of the first and the second instances of the structured light pattern detected by the light sensor.