# US 9,873,196 B2 · Bistatic object detection apparatus and methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,873,196 B2 - Document ID: US9873196B2 - Status: Granted - Kind: B2 - Application number: 14/752,688 - Filed: 2015-06-26 - Published: 2016-12-29 - Granted: 2018-01-23 - Earliest claimed: 2015-06-24 - Assignees: Brain Corporation - Applicants: Brain Corporation - Inventors: Botond Szatmary; Micah Richert - Web page: https://patentgrep.com/patent/US9873196B2 ## CPC - G06V 10/145: Illumination specially adapted for pattern recognition, e.g. using gratings - B25J 5/00: Manipulators mounted on wheels or on carriages (B25J1/00 takes precedence; program-controlled manipulators B25J9/00) - B25J 9/1674: {characterised by safety, monitoring, diagnostic} - B25J 9/1676: {Avoiding collision or forbidden zones} - B25J 11/0085: {Cleaning} - B25J 19/06: Safety devices - B60Q 1/54: for indicating speed {outside of the vehicle} - B60Q 9/008: {for anti-collision purposes} - G01S 7/51: Display arrangements - G01S 17/003: {Bistatic lidar systems; Multistatic lidar systems} - G01S 17/04: Systems determining the presence of a target - G01S 17/46: Indirect determination of position data - G01S 17/89: for mapping or imaging - G01S 17/931: of land vehicles - G05D 1/00: Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots (drive control systems specially adapted for autonomous road vehicles B60W60/00) - G05D 1/0238: {using obstacle or wall sensors (G05D1/0246 and G05D1/0289 take precedence; lidar systems designed for anti-collision purposes G01S17/93)} - G06F 18/22: Matching criteria, e.g. proximity measures - G06V 20/10: Terrestrial scenes (scenes under surveillance with static cameras G06V20/52; scenes perceived from the exterior of a vehicle G06V20/56; scenes perceived from the interior of a vehicle G06V20/59) - G06V 20/52: Surveillance or monitoring of activities, e.g. for recognising suspicious objects (recognising microscopic objects G06V20/69) - G06V 20/58: Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads - G01S 13/931: of land vehicles - G01S 15/931: of land vehicles - G05D 1/0242: {using non-visible light signals, e.g. IR or UV signals} - Y10S 901/01: Mobile robot - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING - B25J: MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES ({manipulators specially adapted for use in surgery A61B34/70; manipulators used in cleaning hollow articles B08B9/04}; manipulators associated with rolling mills B21B39/20; manipulators associated with forging machines B21J13/10; {manipulators associated with picking-up and placing mechanisms B23P19/007}; means for holding wheels or parts thereof B60B30/00; {vehicles with ground-engaging propulsion means, e.g. walking members B62D57/02, B62D57/032; devices for picking-up and depositing articles or materials between conveyors B65G47/90, B65G47/91; manipulators with gripping or holding means for transferring packages B65H67/065}; cranes B66C; {manipulators used in the protection or supervision of pipe-line installations F17D5/00; walking equipment adapted for nuclear steam-generators F22B37/006}; manipulators specially adapted for, or associated with, nuclear reactors G21C; {apparatus used for handling wafers during manufacture or treatment of semiconductor H10P72/50}) - B60Q: ARRANGEMENT OF SIGNALLING OR LIGHTING DEVICES, THE MOUNTING OR SUPPORTING THEREOF OR CIRCUITS THEREFOR, FOR VEHICLES IN GENERAL - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract Apparatus and methods for navigation of a robotic device configured to operate in an environment comprising objects and/or persons. Location of objects and/or persons may change prior and/or during operation of the robot. In one embodiment, a bistatic sensor comprises a transmitter and a receiver. The receiver may be spatially displaced from the transmitter. The transmitter may project a pattern on a surface in the direction of robot movement. In one variant, the pattern comprises an encoded portion and an information portion. The information portion may be used to communicate information related to robot movement to one or more persons. The encoded portion may be used to determine presence of one or more object in the path of the robot. The receiver may sample a reflected pattern and compare it with the transmitted pattern. Based on a similarity measure breaching a threshold, indication of object present may be produced. ## Claims ### Claim 1 A method for detecting an object by a computerized robotic apparatus configured to clean a surface, the method comprising: configuring a reference pattern, the reference pattern comprising a persistent two-dimensional geometric pattern for display on the surface during movement of the robotic apparatus along the surface, the reference pattern further comprising an object detection portion and a second portion comprising information associated with one or more operational characteristics of the movement of the robotic apparatus along the trajectory; projecting the reference pattern onto a surface in front of the robotic apparatus using a light emitter component, the projecting of the reference pattern comprising projecting (i) the object detection portion and (ii) the second portion comprising the information associated with the one or more operational characteristics of the movement of the robotic apparatus; detecting a reflected pattern by a camera component, the camera component being configured to produce a digital image; analyzing the digital image to determine a parameter of the reflected pattern, the analyzing comprising determining a change within the reflected pattern in comparison to the configured reference pattern; and based on the parameter of the reflected pattern breaching a threshold, producing an indication of the object being present in front of the robotic apparatus. ### Claim 2 (depends on 1) The method of claim 1, wherein: the projected reference pattern comprises an encoded portion, the encoded portion comprising a plurality of elements and a background portion; and the encoded portion is configured to produce the reflected pattern characterized by a first area of increased contrast compared to a second area associated with the background portion. ### Claim 3 (depends on 2) The method of claim 2, wherein the act of configuring the reference pattern comprises: selecting a pattern width in accordance with a width of the robotic apparatus; and selecting a pattern length in accordance with a speed of the robotic apparatus. ### Claim 4 (depends on 2) The method of claim 2, wherein: the encoded portion comprises a plurality of lines arranged in a grid configuration; and the act of configuring the reference pattern comprises selecting one or more of a line width and the grid configuration. ### Claim 5 (depends on 4) The method of claim 4, the grid configuration comprises the plurality of elements, the plurality of elements comprising one or more elements of varying width or height. ### Claim 6 (depends on 2) The method of claim 2, wherein: the encoded portion comprises a plurality of rectangles arranged in a grid configuration; and the act of configuring the reference pattern comprises selecting one or more of: rectangle dimensions, a checkerboard-like pattern, and/or the grid configuration. ### Claim 7 (depends on 6) The method of claim 6, wherein the reference pattern comprises the checkerboard-like pattern comprising elements of alternating black and white elements. ### Claim 8 (depends on 1) The method of claim 1, wherein: the projected reference pattern comprises an encoded portion and a target portion; the encoded portion comprises at least one element characterized by a first light characteristic configured to differ from a second light characteristic of the target portion; the parameter of the reflected pattern comprises a height above a surface comprising the at least one element; and the threshold is based on an expected reference width or an expected reference length of the projected reference pattern comprising the at least one element when the object is not present in front of the robotic apparatus. ### Claim 9 (depends on 8) The method of claim 8, wherein the reference width or length corresponds to another reflected pattern projected onto a surface in an absence of the object. ### Claim 10 (depends on 8) The method of claim 8, wherein the at least one element is further characterized by one or both of a light wavelength and a light intensity. ### Claim 11 A robotic apparatus comprising: a bistatic sensor apparatus comprising a transmitter component and a receiver component; a non-transitory computer-readable apparatus comprising a storage medium, the storage medium comprising a plurality of instructions configured to, when executed by a processor apparatus, cause the robotic apparatus to: configure an encoded reference pattern, the encoded reference pattern comprising (i) one or more first portions that represent one or more parameters related to a given task of the robotic apparatus and (ii) a second portion comprising human-readable information related to the given task of the robotic apparatus; project the encoded reference pattern onto a surface at a front side of the robotic apparatus via the transmitter component, the projection of the encoded reference pattern comprising a dynamic adjustment of the one or more first portions thereof and the second portion thereof, the dynamic adjustment being based on a change in the given task of the robotic apparatus; detect a reflected pattern via the receiver component, the receiver component being configured to generate a digital image; analyze the digital image to determine a parameter of the detected reflected pattern; and when the parameter of the detected reflected pattern breaches a threshold, produce an indication of a presence of an object at the front side of the robotic apparatus. ### Claim 12 (depends on 11) The robotic apparatus of claim 11, wherein the robotic apparatus is configured to traverse a premises at a given speed. ### Claim 13 (depends on 11) The robotic apparatus of claim 11, wherein the threshold comprises one or more of a similarity level, a brightness level, and a dimension of the detected reflected pattern. ### Claim 14 (depends on 11) The robotic apparatus of claim 11 wherein: the projected encoded reference pattern comprises an encoded portion, the encoded portion comprising a plurality of elements and a background portion, where the one or more first portions comprise the plurality of elements, and the second portion comprises the background portion; and the encoded portion is configured to produce the reflected pattern characterized by a first area of increased contrast compared to a second area associated with the background portion. ### Claim 15 (depends on 14) The robotic apparatus of claim 14, wherein the configuration of the encoded reference pattern comprises: a selection of a pattern width in accordance with a width of the robotic apparatus; and a selection of a pattern length in accordance with a speed of the robotic apparatus. ### Claim 16 A non-transitory computer-readable apparatus comprising a storage medium, the storage medium comprising a plurality of computer-executable instructions therein, the plurality of instructions being configured to, when executed by a processor apparatus, cause a robotic apparatus to: configure an encoded reference pattern, the encoded reference pattern comprising a first portion and a second portion, the first and the second portions being dynamically selected based on an environmental parameter and a task parameter of a given task of the robotic apparatus; project the encoded reference pattern onto a surface in front of the robotic apparatus using a transmitter component; detect a reflected pattern via a receiver component, the receiver component being configured to produce a digital image; analyze the digital image to determine a parameter of the reflected pattern; and when the parameter of the reflected pattern breaches a threshold, produce an indication of an object being present in front of the robotic apparatus; wherein the encoded reference pattern comprises a two-dimensional spatial pattern, and the breaching of the threshold comprises at least a two-dimensional spatial discrepancy between the encoded reference pattern and the reflected pattern. ### Claim 17 (depends on 16) The non-transitory computer-readable apparatus of claim 16, wherein the plurality of instructions are further configured to, when executed by the processor apparatus, cause the robotic apparatus to identify the surface for the projection of the encoded reference pattern based on an absence of objects. ### Claim 18 (depends on 16) The non-transitory computer-readable apparatus of claim 16, wherein the plurality of instructions are further configured to, when executed by the processor apparatus, cause the robotic apparatus to project the encoded reference pattern onto the surface in front of the robotic apparatus when the surface is substantially free of obstacles. ### Claim 19 (depends on 16) The non-transitory computer-readable apparatus of claim 16, wherein the plurality of instructions are further configured to, when executed by the processor apparatus, cause the robotic apparatus to modify a trajectory of the robotic apparatus in response to the indication of the object being present. ### Claim 20 (depends on 16) The non-transitory computer-readable apparatus of claim 16, wherein: the projected encoded reference pattern comprises an encoded portion and a target portion, the encoded portion and the target corresponding to the first and the second portions; the encoded portion comprises at least one element characterized by a first light characteristic configured to differ from a second light characteristic of the target portion; the parameter of the reflected pattern comprises a height above a surface comprising the at least one element; and the threshold is based on an expected reference width or an expected reference length of the projected reference pattern comprising the at least one element when the object is not present in front of the robotic apparatus. ### Claim 21 (depends on 14) The robotic apparatus of claim 14, wherein the parameter of the reflected pattern comprises one or more of a dimension, an orientation, a photometric measurement, a uniformity, and a deviation relative to the surface.