# US 11,993,305 B2 · System and method for estimating an articulation angle of an articulated vehicle combination > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,993,305 B2 - Document ID: US11993305B2 - Status: Granted - Kind: B2 - Application number: 17/643,060 - Filed: 2021-12-07 - Published: 2022-06-16 - Granted: 2024-05-28 - Earliest claimed: 2020-12-10 - Assignees: Volvo Truck Corporation - Applicants: Volvo Truck Corporation - Inventors: Daniel Persson; Hans Deragården - Web page: https://patentgrep.com/patent/US11993305B2 ## CPC - B62D 15/023: {by measuring on the king pin} - G01B 11/26: for measuring angles or tapers; for testing the alignment of axes - B60R 11/04: Mounting of cameras operative during drive; Arrangement of controls thereof relative to the vehicle - B62D 12/00: Steering specially adapted for vehicles operating in tandem or having pivotally connected frames (steering endless tracks or the like B62D11/00; steering specially adapted for trailers B62D13/00) - G06T 7/60: Analysis of geometric attributes - B60R 2300/105: using multiple cameras - B60R 2300/30: characterised by the type of image processing - B60R 2300/80: characterised by the intended use of the viewing arrangement - B60W 30/18036: {Reversing} - B60W 50/14: Means for informing the driver, warning the driver or prompting a driver intervention - B60W 2300/14: Tractor-trailers, i.e. combinations of a towing vehicle and one or more towed vehicles, e.g. caravans; Road trains - B60W 2556/20: Data confidence level - B60W 2720/22: Articulation angle, e.g. between tractor and trailer - B62D 13/06: for backing a normally drawn trailer - B62D 15/02: Steering position indicators {; Steering position determination; Steering aids} - G06T 2207/30252: Vehicle exterior; Vicinity of vehicle - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) - G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS - B60R: VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT ## Abstract A system for estimating an articulation angle between a first and a second connected vehicle section of an articulated vehicle combination, the system comprising a primary image obtaining device configured to be mounted on a first position of one of the vehicle sections and to obtain images of the other vehicle section during use; a secondary image obtaining device configured to be mounted on a second position of one of the vehicle sections and to obtain images of the other vehicle section during use, the second position being different from the first position, and/or a mounting orientation at the second position of the second image obtaining device being different from a mounting orientation at the first position of the primary image obtaining device. ## Claims ### Claim 1 A system for estimating an articulation angle between a first and a second connected vehicle section of an articulated vehicle combination, the system comprising: a primary image obtaining device configured to be mounted on a first position of one of the vehicle sections and to obtain images of the other vehicle section during use; a secondary image obtaining device configured to be mounted on a second position of one of the vehicle sections and to obtain images of the other vehicle section during use, the second position being different from the first position, and/or a mounting orientation at the second position of the secondary image obtaining device being different from a mounting orientation at the first position of the primary image obtaining device; and wherein the system is configured to: estimate the articulation angle by use of at least one obtained image from the primary image obtaining device; determine if an unreliability condition has been fulfilled which indicates that the articulation angle cannot be reliably estimated from the at least one obtained image from the primary image obtaining device; and when the unreliability condition has been fulfilled, the system is further configured to: estimate the articulation angle by use of at least one obtained image from the secondary image obtaining device. ### Claim 2 (depends on 1) The system according to claim 1, wherein the primary image obtaining device is an optical image obtaining device, such as a camera or a LIDAR, wherein the unreliability condition is a condition considered fulfilled when a light intensity in the obtained images of the primary image obtaining device is outside a predetermined light intensity range. ### Claim 3 (depends on 2) The system according to claim 2, wherein the predetermined light intensity range is defined by at least one of: an upper limit associated with a too high light intensity, such as caused by direct or reflected sunlight and light from headlamps at night; a lower limit associated with a too low light intensity, such as dark/night conditions and dirt and/or water splash on the primary image obtaining device. ### Claim 4 (depends on 1) The system according to claim 1, wherein the articulation angle is estimated by determining a relative position and/or orientation of the first and second vehicle sections from the at least one obtained image. ### Claim 5 (depends on 1) The system according to claim 1, wherein, when the unreliability condition is fulfilled, the articulation angle is estimated by determining an articulation angle change by use of the secondary image obtaining device and by using an absolute articulation angle estimated at least by use of the primary image obtaining device before the unreliability condition was fulfilled. ### Claim 6 (depends on 5) The system according to claim 5, wherein the secondary image obtaining device is calibrated by use of the at least one obtained image from the primary image obtaining device. ### Claim 7 (depends on 1) The system according to claim 1, wherein the secondary image obtaining device is any one of a camera, a LIDAR, a RADAR, an ultrasonic sensor and a SONAR. ### Claim 8 (depends on 1) The system according to claim 1, wherein, when the unreliability condition is not fulfilled, the articulation angle is estimated by use of the primary and the secondary image obtaining devices. ### Claim 9 (depends on 1) A vehicle comprising at least parts of the system according to claim 1, wherein at least the primary image obtaining device is preferably mounted on the vehicle. ### Claim 10 (depends on 9) The vehicle according to claim 9, wherein the primary image obtaining device is mounted at a rearward facing side of the vehicle, such as on a rear side of a vehicle cabin or on a rearward facing side of a vehicle chassis, such as behind and/or below a vehicle coupling point. ### Claim 11 (depends on 9) The vehicle according to claim 9, wherein the second position is any one of a position on a lateral side of the vehicle and on the rearward facing side of the vehicle. ### Claim 12 (depends on 9) An articulated vehicle combination comprising a first and a second vehicle section, wherein the first vehicle section is the vehicle according to claim 9. ### Claim 13 (depends on 12) The articulated vehicle combination according to claim 12, wherein the secondary image obtaining device is mounted on the second vehicle section. ### Claim 14 A method for an articulated vehicle combination for estimating an articulation angle between a first and a second connected vehicle section of the articulated vehicle combination, wherein the articulated vehicle combination comprises: a primary image obtaining device mounted on a first position of one of the vehicle sections; a secondary image obtaining device mounted on a second position of one of the vehicle sections, the second position being different from the first position, and/or a mounting orientation at the second position of the secondary image obtaining device being different from a mounting orientation at the first position of the primary image obtaining device; wherein the method comprises: obtaining at least one image of the other vehicle section by the primary image obtaining device; estimating the articulation angle by use of the at least one obtained image from the primary image obtaining device; determining if an unreliability condition has been fulfilled which indicates that the articulation angle cannot be reliably estimated from the at least one obtained image from the primary image obtaining device; and when the unreliability condition has been fulfilled, the method further comprises: obtaining at least one image of the other vehicle section by the secondary image obtaining device; and estimating the articulation angle by use of the at least one obtained image from the secondary image obtaining device. ### Claim 15 (depends on 14) A control unit for an articulated vehicle combination for estimating an articulation angle between a first and a second connected vehicle section of the articulated vehicle combination, wherein the control unit is configured to perform the method of claim 14.