# US 2014/0229070 A1 · Trailer reverse assist control > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0229070 A1 - Document ID: US20140229070A1 - Status: Published application - Kind: A1 - Application number: 13/765,122 - Filed: 2013-02-12 - Published: 2014-08-14 - Earliest claimed: 2013-02-12 - Assignees: GM Global Technology Operations LLC - Applicants: GM Global Technology Operations LLC - Inventors: Daniel F. Witting - Web page: https://patentgrep.com/patent/US20140229070A1 ## CPC - B62D 13/06: for backing a normally drawn trailer - B60D 1/245: {for facilitating push back or parking of trailers} - B60D 1/62: involving supply lines, electric circuits or the like - B62D 15/0275: {by overlaying a vehicle path based on present steering angle over an image without processing that image} - 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) - B60D: VEHICLE CONNECTIONS ## Abstract A trailer reverse assist system for a vehicle coupled to a trailer is provided. The trailer reverse assist system includes a park assist controller configured to receive a distance input from at least one rear distance sensor. The park assist controller is configured to determine a pitch angle of the trailer relative to the vehicle based on the distance input. An electronic power steering system is coupled to the park assist controller. The electronic power steering system is configured to adjust a hand wheel angle of the vehicle based on the pitch angle of the trailer. ## Claims ### Claim 1 A trailer reverse assist system for a vehicle coupled to a trailer, the trailer reverse assist system comprising: a park assist controller configured to receive a distance input from at least one rear distance sensor, the park assist controller configured to determine a pitch angle of the trailer relative to the vehicle based on the distance input; and an electronic power steering system coupled to the park assist controller, the electronic power steering system configured to adjust a hand wheel angle of the vehicle based on the pitch angle of the trailer. ### Claim 2 (depends on 1) The trailer reverse assist system of claim 1, wherein the park assist controller comprises a distance determination module configured to determine a distance between the vehicle and a target location of the trailer based on the distance input. ### Claim 3 (depends on 2) The trailer reverse assist system of claim 2, wherein the park assist controller further comprises a pitch angle determination module in communication with the distance determination module and configured to determine the pitch angle of the trailer relative to the vehicle based on the distance between the vehicle and the target location of the trailer. ### Claim 4 (depends on 3) The trailer reverse assist system of claim 3, wherein the target location of the trailer is a wheel of the trailer. ### Claim 5 (depends on 1) The trailer reverse assist system of claim 1, wherein the at least one rear distance sensor comprises one or more of: an ultrasonic sensor, an infrared sensor, and a rear vision system. ### Claim 6 (depends on 1) The trailer reverse assist system of claim 1, further comprising a control module configured to: receive a vehicle speed, the hand wheel angle, the pitch angle of the trailer, and an intended path of the trailer; determine a hand wheel command to adjust the hand wheel angle and align the pitch angle of the trailer with the intended path of the trailer based on the vehicle speed, the hand wheel angle, the pitch angle of the trailer, and the intended path of the trailer; and output the hand wheel command to a power steering motor of the electronic power steering system. ### Claim 7 (depends on 6) The trailer reverse assist system of claim 6, wherein the control module is in communication with a trailer reverse assist control switch and a transmission gear selector, and the trailer reverse assist system is enabled responsive to a state of the trailer reverse assist control switch being enabled and the transmission gear selector being set to reverse. ### Claim 8 (depends on 6) The trailer reverse assist system of claim 6, further comprising a display system configured to display the intended path of the trailer, the display system comprising one or more of: an active display rearview mirror and a dashboard display. ### Claim 9 (depends on 6) The trailer reverse assist system of claim 6, wherein the control module updates the hand wheel command such that a difference between the pitch angle of the trailer and the intended path of the trailer is maintained within a predetermined angle threshold. ### Claim 10 (depends on 9) The trailer reverse assist system of claim 9, wherein the intended path of the trailer is a fixed angle based on an initial alignment of the vehicle relative to the trailer upon enabling the trailer reverse assist system, and the pitch angle of the trailer is further determined based on a variation from the initial alignment. ### Claim 11 A method for trailer reverse assist for a vehicle coupled to a trailer, the method comprising: receiving, at a park assist controller, a distance input from at least one rear distance sensor; determining, by the park assist controller, a pitch angle of the trailer relative to the vehicle based on the distance input; providing the pitch angle of the trailer and a hand wheel angle of the vehicle to an electronic power steering system; and adjusting, by the electronic power steering system, the hand wheel angle of the vehicle based on the pitch angle of the trailer. ### Claim 12 (depends on 11) The method of claim 11, further comprising determining a distance between the vehicle and a target location of the trailer based on the distance input. ### Claim 13 (depends on 12) The method of claim 12, further comprising determining the pitch angle of the trailer relative to the vehicle based on the distance between the vehicle and the target location of the trailer. ### Claim 14 (depends on 13) The method of claim 13, wherein the target location of the trailer is a wheel of the trailer. ### Claim 15 (depends on 11) The method of claim 11, wherein the at least one rear distance sensor comprises one or more of: an ultrasonic sensor, an infrared sensor, and a rear vision system. ### Claim 16 (depends on 11) The method of claim 11, further comprising: receiving a vehicle speed, the hand wheel angle, the pitch angle of the trailer, and an intended path of the trailer at a control module; determining, by the control module, a hand wheel command to adjust the hand wheel angle and align the pitch angle of the trailer with the intended path of the trailer based on the vehicle speed, the hand wheel angle, the pitch angle of the trailer, and the intended path of the trailer; and outputting the hand wheel command to a power steering motor of the electronic power steering system. ### Claim 17 (depends on 16) The method of claim 16, further comprising: determining a state of a trailer reverse assist control switch and a transmission gear selector; and performing the adjusting of the hand wheel angle based on the trailer reverse assist control switch being enabled and the transmission gear selector being set to reverse. ### Claim 18 (depends on 16) The method of claim 16, further comprising displaying the intended path of the trailer on a display system, the display system comprising one or more of: an active display rearview mirror and a dashboard display. ### Claim 19 (depends on 16) The method of claim 16, further comprising updating the hand wheel command such that a difference between the pitch angle of the trailer and the intended path of the trailer is maintained within a predetermined angle threshold. ### Claim 20 (depends on 19) The method of claim 19, wherein the intended path of the trailer is a fixed angle based on an initial alignment of the vehicle relative to the trailer upon enabling trailer reverse assistance, and the pitch angle of the trailer is further determined based on a variation from the initial alignment.