# Patent

## Title
Trailer backup assist system with hitch assist

## Abstract

A hitch assist system is provided herein. An imaging device captures images of a scene rearward of a vehicle. A controller processes captured images and is configured to control a vehicle suspension system to adjust a height of the vehicle and control the deployment of a power tongue jack of a trailer.

## Background
FIELD OF THE INVENTION
The present invention generally relates to trailer backup assist systems, and more particularly, to trailer backup assist systems employing hitch assist functionality.
BACKGROUND OF THE INVENTION
Making or removing a hitch connection between a vehicle and a trailer can be time consuming and difficult, especially for those who are inexperienced. As such, there is a need for a system that assists a user in the hitching and unhitching of a vehicle to and from a trailer.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, a hitch assist system is provided. An imaging device captures images of a scene rearward of a vehicle. A controller processes captured images and is configured to control a vehicle suspension system to adjust a height of the vehicle and control the deployment of a power tongue jack of a trailer.
According to another aspect of the present invention, a method of hitching a vehicle to a trailer is provided. A controller is provided and is configured to autonomously back the vehicle toward the trailer, control a vehicle suspension system to adjust a height of the vehicle such that a hitch connection can be made between a hitch ball and a coupler ball socket, and control a power tongue jack of the trailer to move between a deployed position and a retracted position.
According to yet another aspect of the present invention, a method of unhitching a vehicle from a trailer is provided. A controller is provided and is configured to control a vehicle suspension system to adjust a height of the vehicle such that a hitch ball can become unhitched from a coupler ball socket and control a power tongue jack of the trailer to move between a retracted position and a deployed position.
These and other features, advantages, and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and appended drawings.



BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a top perspective view of a vehicle and a trailer in an unhitched position;
FIG. 2 is a block diagram illustrating one embodiment of a trailer backup assist system;
FIG. 3 illustrates a target on a tongue of the trailer;
FIG. 4 illustrates a portable electronic device secured in a docking stating coupled to the tongue of the trailer;
FIG. 5 is a flow diagram of a method for hitching the vehicle to the trailer;
FIG. 6 illustrates the vehicle being backed toward the trailer, wherein a power tongue jack of the trailer is in a deployed position such that a coupler ball socket is elevated to provide sufficient clearance for a hitch ball;
FIG. 7 illustrates the vehicle being raised so that the hitch ball is seated in the coupler ball socket;
FIG. 8 is a flow diagram of a method for unhitching the vehicle from the trailer;
FIG. 9 illustrates the vehicle being raised to provide sufficient clearance for the deployment of the power tongue jack; and
FIG. 10 illustrates the vehicle being lowered to a ride height once the power tongue jack has been deployed.



DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
For purposes of description herein, it is to be understood that the disclosed trailer backup assist system and the related methods may assume various alternative embodiments and orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the inventive concepts defined in the appended claims. While various aspects of the trailer backup assist system and the related methods are described with reference to a particular illustrative embodiment, the disclosed invention is not limited to such embodiments, and additional modifications, applications, and embodiments may be implemented without departing from the disclosed invention. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.
As used herein, the term “and/or,” when used in a list of two or more items, means that any one of the listed items can be employed by itself, or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and/or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.
Referring to FIGS. 1 and 2, reference numeral 10 generally designates a trailer backup assist system capable of aligning a vehicle 12 with a trailer 14 so that the trailer 14 can be hitched to the vehicle 12. As shown in FIG. 1, the vehicle 12 is exemplarily embodied as a pickup truck having a truck bed 16 that is accessible via a fold down tailgate 18. The vehicle 12 also includes a vehicle hitch connector in the form of a drawbar 22 that extends from the rear of the vehicle 12 and terminates in a hitch ball 24. The hitch ball 24 is configured to be received by a trailer hitch connector in the form of a coupler ball socket 26 that is provided at a terminal end of a tongue 28 of the trailer 14. The trailer 14 is exemplarily embodied as a single axle trailer having a box frame 30 with an enclosed cargo area 32 from which the tongue 28 extends longitudinally. A power tongue jack 36 is mounted to the tongue 28 and is automatically operated to raise the tongue 28 to provide sufficient clearance for the hitch ball 24. The power tongue jack 36 may include its own power source or be electrically connected to a power source of the vehicle 12. Alternatively, a manually operated tongue jack may be employed in other embodiments.
According to one embodiment, the power tongue jack 36 may be communicatively coupled to a controller 38 (FIG. 2) of the trailer backup assist system 10 in a wired or wireless (e.g., BLUETOOTH®) manner. In operation, the controller 38 may prompt the power tongue jack 36 to deploy or withdraw as needed in order for the vehicle 12 and trailer 14 to be hitched together or become unhitched. As will be described further herein, the hitching or unhitching of the vehicle 12 to and from the trailer 14 may be performed autonomously or semi-autonomously by the trailer backup assist system 10. To realize this, the controller 38 of the trailer backup assist system 10 may communicate with a number of vehicle equipment, which will be described further below.
In one embodiment, the controller 38 may communicate with an imaging device 40 located at the rear of the vehicle 12. The imaging device 40 may be centrally located at an upper region of the tailgate 18 such that the imaging device 40 is elevated relative to the drawbar 22 and the hitch ball 24. The imaging device 40 has a field of view 42 located and oriented to capture one or more images of a rear-vehicle scene that generally includes the hitch ball 24, among other things, when the vehicle 12 is not hitched to the trailer 14. Images captured by the imaging device 40 are processed by the controller 38 to identify a trailer hitch connection such as the coupler ball socket 26. In turn, the trailer backup assist system 10 is able to guide the vehicle 12 in a manner such that a hitch connection can be made between the vehicle 12 and the trailer 14. It is contemplated that the coupler ball socket 26 may be identified via imaging methods such as edge detection and the like. Alternatively, it is contemplated that the coupler ball socket 26 may be identified by using the imaging device 40 to track a target 43 (FIG. 3) provided on the tongue 28 and located on or proximate the coupler ball socket 26. As shown in FIG. 3, the target 43 may be positioned on the tongue 28 of the trailer 14 and include a pattern that is recognizable through image processing.
In addition to communicating with the imaging device 40, the controller 38 may communicate with a number of proximity sensors, exemplarily shown as ultrasonic sensors 44 (FIG. 1), which are spaced across a lower region of the vehicle tailgate 18 and configured to detect the proximity or distance of objects located rearward of the vehicle 12. With reference to the embodiment of the trailer backup assist system 10 shown in FIG. 2, additional vehicle-related information may be provided to the controller 38 by a positioning device 46, such as a global positioning system (GPS) located on the vehicle 12. The positioning device 46 may additionally or alternatively include a dead reckoning system for determining the coordinate location of the vehicle 12 within a localized coordinate system based on vehicle dynamics such as vehicle speed and steering angle. Additionally, the controller 38 may communicate with an inertial system 47 including one or more gyroscopes 48 and accelerometers 49 to measure the position, orientation, direction, and/or speed of the vehicle 12. It is also contemplated that the controller 38 may communicate with a portable electronic device 50, such as a smartphone, located in the vehicle 12 or on the trailer 14, and from which vehicle or trailer-related information may be obtained. For example, in one embodiment, the portable electronic device 50 may be secured to a docking station 51 (FIG. 4) provided on the tongue 28 of the trailer 14 located on or proximate the coupler ball socket 26. The portable electronic device 50 may be equipped with GPS in order to communicate the position of the coupler ball socket 26 to the controller 38. In this manner, the portable electronic device 50 functions as an active target that transmits the position of coupler ball socket 26 to the controller 38.
To effectuate autonomous control of the vehicle 12, the controller 38 of trailer backup assist system 10 may be further configured to communicate with a variety of vehicle equipment. According to one embodiment, the controller 38 of the trailer backup assist system 10 may control a power assist steering system 52 of the vehicle 12 to operate the steered wheels 53 (FIG. 1) of the vehicle 12 while the vehicle 12 is backed toward the trailer 14. In instances where the trailer 14 is hitched to the vehicle 12, the controller 38 may control the power assist steering system 52 in such a manner that the trailer 14 is backed along a desired backing path. The power assist steering system 52 may be an electric power-assisted steering (EPAS) system that includes an electric steering motor 54 for turning the steered wheels 53 to a steering angle based on a steering command generated by the controller 38, whereby the steering angle may be sensed by a steering angle sensor 56 of the power assist steering system 52 and provided to the controller 38. As described herein, the steering command may be provided for autonomously steering the vehicle 12 during a backup maneuver and may alternatively be provided manually via a rotational position (e.g., a steering wheel angle) of a steering wheel 58 or a steering input device 60, which may be provided to enable a driver to control or otherwise modify the desired curvature of the backing path of vehicle 12. The steering input device 60 may be communicatively coupled to the controller 38 in a wired or wireless manner and provides the controller 38 with information defining the desired curvature of the backing path of the vehicle 12. In response, the controller 38 processes the information and generates corresponding steering commands that are supplied to the power assist steering system 52 of the vehicle 12. In one embodiment, the steering input device 60 includes a rotatable knob 62 operable between a number of rotated positions that each provide an incremental change to the desired curvature of the backing path of the vehicle 12.
In some embodiments, the steering wheel 58 of the vehicle 12 may be mechanically coupled with the steered wheels 53 of the vehicle 12, such that the steering wheel 58 moves in concert with steered wheels 53 via an internal torque, thereby preventing manual intervention with the steering wheel 58 during autonomous steering of the vehicle 12. In such instances, the power assist steering system 52 may include a torque sensor 64 that senses torque (e.g., gripping and/or turning) on the steering wheel 58 that is not expected from autonomous control of the steering wheel 58 and therefore indicative of manual intervention by the driver. In some embodiments, external torque applied to the steering wheel 58 may serve as a signal to the controller 38 that the driver has taken manual control and for the trailer backup assist system 10 to discontinue autonomous steering functionality.
With continued reference to FIG. 2, the controller 38 of the trailer backup assist system 10 may also communicate with a vehicle brake control system 66 of the vehicle 12 to receive vehicle speed information such as individual wheel speeds of the vehicle 12. Additionally or alternatively, vehicle speed information may be provided to the controller 38 by a powertrain control system 68 and/or a vehicle speed sensor 70, among other conceivable means. In some embodiments, the controller 38 may provide braking commands to the vehicle brake control system 66, thereby allowing the trailer backup assist system 10 to regulate the speed of the vehicle 12 during a backup maneuver of the vehicle 12. It should be appreciated that the controller 38 may additionally or alternatively regulate the speed of the vehicle 12 via interaction with the powertrain control system 68. In some embodiments, the vehicle 12 may be equipped with an adjustable suspension system 71 capable of raising and lowering the vehicle 12. For vehicles equipped with such functionality, it is contemplated that the controller 38 may communicate with the suspension system 71 to control the height of the vehicle 12 to allow the vehicle 12 to be hitched to or unhitched from the trailer 14.
Through interaction with the power assist steering system 52, the vehicle brake control system 66, and/or the powertrain control system 68 of the vehicle 12, the potential for unacceptable backup conditions can be reduced when the vehicle 12 is backing alone or with the trailer 14. Examples of unacceptable trailer backup conditions include, but are not limited to, a vehicle over-speed condition, a high hitch angle rate, hitch angle dynamic instability, a trailer jackknife condition, sensor failure, and the like. In such circumstances, the driver may be unaware of the failure until the unacceptable trailer backup condition is imminent or already happening. Therefore, it is disclosed herein that the controller 38 of the trailer backup assist system 10 can generate an alert signal corresponding to a notification of an actual, impending, and/or anticipated unacceptable backup condition, and prior to driver intervention, generate a counter measure to prevent such an unacceptable trailer backup condition.
According to one embodiment, the controller 38 may communicate with one or more devices, including a vehicle alert system 72, which may prompt visual, auditory, and tactile warnings. For instance, vehicle brake lights 74 and vehicle emergency flashers may provide a visual alert and a vehicle horn 76 and/or speaker 78 may provide an audible alert. Additionally, the controller 38 and/or vehicle alert system 72 may communicate with a human machine interface (HMI) 80 of the vehicle 12. The HMI 80 may include a touchscreen vehicle display 82 (FIG. 1) such as a center-stack mounted navigation or entertainment display capable of displaying images indicating the alert. Such an embodiment may be desirable to notify the driver of the vehicle 12 that an unacceptable backup condition is present.
With further reference to FIG. 2, the controller 38 is configured with a microprocessor 84 and/or other analog and/or digital circuitry for processing one or more logic routines stored in a memory 86. The logic routines may include one or more operating routines 88. Information from the imaging device 40 or other components of the trailer backup assist system 10 can be supplied to the controller 38 via a communication network of the vehicle 12, which can include a controller area network (CAN), a local interconnect network (LIN), or other conventional protocols used in the automotive industry. It should be appreciated that the controller 38 may be a stand-alone dedicated controller or may be a shared controller integrated with the imaging device 40 or other component of the trailer backup assist system 10 in addition to any other conceivable onboard or off-board vehicle control systems.
Referring to FIG. 5, a flow diagram of a method of hitching the vehicle 12 to the trailer 14 is shown. The method is shown as one embodiment of the operating routine 88 and is executed by the controller 38 of the trailer backup assist system 10. For purposes of illustration, certain steps of the method will be described with reference to FIGS. 6 and 7. In describing the method, it is assumed that the trailer 14 is a new a trailer, or in other words, the vehicle 12 is being hitched to the trailer 14 for the first time. At step 100, the driver indicates to the trailer backup assist system 10 that a hitching maneuver is desired. This may be done by inputting commands via the display 82 of the HMI 80 or other use-input device of the vehicle 12. At step 110, the driver is instructed to back the vehicle 12 toward the trailer 14 until the vehicle 12 and the trailer 14 are in substantial alignment longitudinally. The instructions may be visual, appearing on the display 82, and/or auditory. Making sure that the trailer 14 is behind the vehicle 12 enables images of the trailer 14 to be captured by the imaging device 40 as well as distance measurements to be taken by the ultrasonic sensors 44. The vehicle 12 is generally shown in front of the trailer 14 in FIG. 6. As shown, the power tongue jack 36 is in a deployed position such that the coupler ball socket 26 is elevated to provide sufficient clearance for the hitch ball 24.
Next, at step 120, the vehicle 12 is backed toward the trailer 14. According to one embodiment, the backing of the vehicle 12 may be done autonomously or semi-autonomously by the controller 38 through the control of the power assist steering system 52, the vehicle brake control system 66, and/or the powertrain control system 68 of the vehicle 12. In instances where the backing of the vehicle 12 is semi-autonomous, it is contemplated that the driver may be instructed to perform the requisite actions such that the vehicle 12 can be backed toward the trailer 14. As the vehicle 12 is being backed toward the trailer 14, the controller 38 detects the presence of the trailer 14 in images captured by the imaging device 40 at step 130. In so doing, the controller 38 is able to locate the coupler ball socket 26 and output steering commands to the power assist steering system 52 such that the drawbar 22 of the vehicle 12 maintains proper alignment with the coupler ball socket 26. At the same time, the controller 38 may receive distance measurements from the ultrasonic sensors 44 to detect the location of the coupler ball socket 26 relative to the vehicle 12 at step 140. Based on the processing of the images, distance measurements received from the ultrasonic sensors 44, and the known length of the drawbar 22, the vehicle 12 is stopped when the hitch ball 24 is located below the coupler ball socket 26 at step 150. At step 160, the controller 38 controls the suspension system 71 of the vehicle 12 to raise the vehicle 12 until the hitch ball 24 is seated in the coupler ball socket 26, as shown in FIG. 7. Once the hitch ball 24 is seated in the coupler ball socket 26, the controller 38 may issue a command to the power tongue jack 36 to withdraw from the deployed position at step 170. Alternatively, the power tongue jack 36 may be manually withdrawn from the deployed position. Next, at step 180, the controller 38 issues a command to the suspension system 71 to lower the vehicle 12 to a ride height for driving, at which point the driver is free to drive off with the trailer 14 in tow.
Referring to FIG. 8, a flow diagram of a method of unhitching the vehicle 12 to the trailer 14 is shown. The method is shown as one embodiment of the operating routine 88 and is executed by the controller 38 of the trailer backup assist system 10. For purposes of illustration, certain steps of the method will be described with reference to FIGS. 9 and 10. In describing the method, it is assumed that trailer 14 is in a final parking position and the driver now intends on unhitching the vehicle 12 from the trailer 14. At step 200 the driver indicates to the trailer backup assist system 10 that an unhitching maneuver is desired. This may be done by inputting commands via the display 82 of the HMI 80 or other use-input device of the vehicle 12. Having indicated that an unhitching maneuver is desired, the controller 38 stores the position of the vehicle 12 to memory 86 at step 210. The stored position may include a GPS coordinate position of the vehicle 12 received from the positioning device 46 along with inertial information of the vehicle 12 as measured by the inertial system 47 of the vehicle 12. At step 220, the controller 38 issues a command to the suspension system 71 to raise the vehicle 12, as shown in FIG. 9, thereby providing sufficient clearance for the deployment of the power tongue jack 36. At step 230, the controller issues a command to the power tongue jack 36 to deploy. Alternatively, deployment of the power tongue jack 36 may be performed manually. At step 240, the controller 38 issues a command to the suspension system 71 to lower the vehicle 12 to the ride height once the power tongue jack 36 has been deployed, as shown in FIG. 10. During the lowering process, the power tongue jack 36 catches the ground, thereby causing the hitch ball 24 to become unseated from the coupler ball socket 26. Once the vehicle 12 reaches the ride height, the driver is free to drive away from the trailer 14.
When it is desired to hitch the vehicle 12 to the trailer 14 at a later time, the trailer backup assist system 10 may autonomously or semi-autonomously control the vehicle 12 to position the vehicle 12 according to the stored position saved previously to memory 86 at step 210, thereby ensuring that the hitch ball 24 is located below the coupler ball socket 26 of the trailer 14. The vehicle 12 can then be hitched to the trailer 14 pursuant to steps 150-170 as outlined in the method described with reference to FIG. 5. It should be appreciated that multiple stored positions of the trailer 14 can be saved to memory 86, each associated with multiple trailers. In this manner, when the driver desires to hitch the vehicle 12 to a specific trailer, the driver need simply recall the corresponding stored position of the vehicle 12. In turn, the trailer backup assist system 10 guides the vehicle 12 to the stored position so that the vehicle 12 can be hitched to the trailer 14. The stored position(s) may be accessed through one or more menus displayed on the display 82 of the vehicle 12.
It is to be understood that variations and modifications can be made on the aforementioned structures and methods without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.

## Claims

1. A hitch assist system comprising:
an imaging device for capturing images of a scene rearward of a vehicle;
a controller for processing captured images, the controller further configured to:
control a vehicle suspension system to adjust a height of the vehicle; and
control the deployment of a power tongue jack of a trailer.

2. The hitch assist system of claim 1, further comprising ultrasonic sensors for distance measurement of objects located behind the vehicle.

3. The hitch assist system of claim 1, wherein the controller processes captured images to determine the location of a coupler ball socket of the trailer.

4. The hitch assist system of claim 1, wherein the controller issues commands for autonomously backing the vehicle toward the trailer.

5. The hitch assist system of claim 1, wherein the controller determines the location of a coupler ball socket of the trailer based on information received from a portable electronic device located on a tongue of the trailer.

6. The hitch assist system of claim 1, further comprising a positioning device and an inertial system for measuring vehicle-related information including at least one of a vehicle position and a vehicle orientation, wherein when the vehicle-related information is stored to a memory of the controller.

7. The hitch assist system of claim 6, wherein the vehicle-related information is used to guide the vehicle in a backing maneuver toward the trailer such that a hitch ball of the vehicle is aligned with a coupler ball socket of the trailer.

8. A method of hitching a vehicle to a trailer, comprising the steps of:
providing a controller configured to:
autonomously back the vehicle toward the trailer;
control a vehicle suspension system to adjust a height of the vehicle such that a hitch connection can be made between a hitch ball and a coupler ball socket; and
control a power tongue jack of the trailer to move between a deployed position and a retracted position.

9. The method of claim 8, wherein the controller is further configured to process images captured by an imaging device to determine the location of the coupler ball socket.

10. The method of claim 8, further comprising the step of using ultrasonic sensors to determine a distance of the coupler ball socket relative to the vehicle.

11. The method of claim 8, wherein the vehicle is backed toward the trailer until the hitch ball is positioned below the coupler ball socket.

12. The method of claim 11, wherein the controller issues a command to the suspension system to raise the vehicle such that the hitch ball is seated in the coupler ball socket.

13. The method of claim 12, wherein the controller issues a command to the power tongue jack to retract from the deployed position.

14. The method of claim 13, wherein controller issues a command to the suspension system to lower the vehicle to a ride height.