Parking path generation device and parking control device

Abstract

To provide a parking route generation device and a parking control device which can easily generate a parking route including a returning that has advance and retreat according to an actual environment.SOLUTION: A parking route generation device 16 comprises: a parking start position acquisition part 21 which acquires a parking start position A1 of a combination vehicle 2 based on current position of the combination vehicle 2; a parking target position setting part 22 which sets a parking target position A2 of the combination vehicle 2 based on the information including the current position of the combination vehicle 2; a return position setting part 23 which sets a return position A3 of the combination vehicle 2 based on the parking start position A1, the parking target position A2 and peripheral environment of the combination vehicle 2; and a target rout generation part 24 which generates a first target route R1 of a trailer 4 from the parking start position A1 to the return position A3 and a second target route R2 of the trailer 4 from the return position A3 to the parking target position A2 based on the parking start position A1, the parking target position A2, and the return position A3.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a parking path generating device and a parking control device. [Background technology]

[0002] For example, Patent Document 1 describes a reverse parking assist device that assists in reverse parking of an articulated vehicle equipped with a tractor and a trailer. The reverse parking assist device described in Patent Document 1 creates a parking target route from the vehicle's position to the parking target position, and sets the steering angle of the articulated vehicle so that the articulated vehicle moves along the parking target route. At this time, a travel trajectory of the articulated vehicle when tracking control is performed using the Pure Pursuit method for the parking target route is created. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-199458 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, when a combination vehicle is parked in a parking lot or the like, it is often necessary to reverse and then go forward. However, in the above-mentioned conventional technology, only a reverse route is generated. Therefore, it is not possible to automatically generate a parking route that includes a forward and reverse turnaround.

[0005] An object of the present invention is to provide a parking path generating device and a parking control device that can easily generate a parking path that includes forward and reverse turns in accordance with the actual environment. [Means for solving the problem]

[0006] One aspect of the present invention is a parking path generation device that generates a parking path for parking an articulated vehicle equipped with a tractor and a trailer, the parking path generation device including a position detection unit that detects the current position of the articulated vehicle, an environment detection unit that detects the surrounding environment of the articulated vehicle, a parking start position acquisition unit that acquires a parking start position of the articulated vehicle using the current position of the articulated vehicle detected by the position detection unit, a parking target position setting unit that sets a parking target position of the articulated vehicle using information including the current position of the articulated vehicle detected by the position detection unit, a turn back position setting unit that sets a turn back position of the articulated vehicle using the parking start position acquired by the parking start position acquisition unit, the parking target position set by the parking target position setting unit, and the surrounding environment of the articulated vehicle detected by the environment detection unit, and The parking control system includes a target path generating unit that generates a first target path for the trailer from the parking start position to the turn position and a second target path for the trailer from the turn position to the parking target position based on the obtained parking start position, the parking target position set by the parking target position setting unit, and the turn position set by the turn position setting unit, and a movement path calculation unit that calculates a movement path of the tractor based on the first target path and the second target path generated by the target path generating unit, and the target path generating unit generates, as the first target path, a geometric path having a curved portion whose curvature changes continuously from the parking start position to the turn position, and generates, as the second target path, a geometric path having a curved portion whose curvature changes continuously from the turn position to the parking target position.

[0007] In such a parking path generating device, the parking start position of the articulated vehicle is acquired using the current position of the articulated vehicle, and the parking target position of the articulated vehicle is set using information including the current position of the articulated vehicle. In addition, the turning position of the articulated vehicle is set using the parking start position and parking target position of the articulated vehicle and the surrounding environment of the articulated vehicle. At this time, the turning position is set so that the articulated vehicle does not come into contact with obstacles present in the vicinity, taking into account the surrounding environment of the articulated vehicle. Then, based on the parking start position, parking target position and turning position of the articulated vehicle, a first target path of the trailer from the parking start position to the turning position and a second target path of the trailer from the turning position to the parking target position are generated. Then, based on the first target path and the second target path of the trailer, the movement path of the tractor is calculated. Here, as the first target path of the trailer, a geometric path having a curved portion whose curvature changes continuously from the parking start position to the turning position is generated. As the second target path of the trailer, a geometric path having a curved portion whose curvature changes continuously from the turning position to the parking target position is generated. Therefore, smooth first and second target routes are generated from the parking start position to the parking target position, taking into account the attitude of the articulated vehicle. This allows a parking route that includes forward and backward turns to be easily generated according to the actual environment.

[0008] The parking path generation device may further include a data series calculation unit that calculates a data series of the steering angle of the tractor and a data series of each attitude angle of the tractor and the trailer by performing a vehicle motion simulation using a geometric model of the articulated vehicle to perform forward tracking control of the articulated vehicle from the parking start position and the parking target position to the turning back position, after the movement path of the tractor is calculated by the movement path calculation unit.

[0009] In such a configuration, a vehicle motion simulation is performed in which the articulated vehicle is controlled to follow forward travel from the parking start position and the parking target position to the turn-around position, respectively, to calculate a data series of the steering angle of the tractor and a data series of the attitude angles of the tractor and trailer that ensure a stable coupling angle. Also, when parking the articulated vehicle at the parking target position, the steering control of the tractor is performed in accordance with the data series of the steering angle of the tractor and the data series of the attitude angles of the tractor and trailer, thereby making it possible to guide the articulated vehicle along the parking path to the parking target position with high accuracy.

[0010] The parking path generation device further includes a curvature constraint determination unit that determines whether the maximum curvature of the geometric paths, which are the first target path and the second target path, is equal to or less than the maximum turning curvature of the trailer, and the movement path calculation unit calculates the movement path of the tractor when the curvature constraint determination unit determines that the maximum curvature of the geometric path is equal to or less than the maximum turning curvature, and the turn position setting unit may re-set the turn position when the curvature constraint determination unit determines that the maximum curvature of the geometric path is not equal to or less than the maximum turning curvature.

[0011] In this configuration, the maximum curvature of the geometric path that is the first and second target paths of the trailer is equal to or less than the maximum turning curvature of the trailer that is determined by the maximum steering angle of the tractor and the maximum coupling angle between the tractor and the trailer. Therefore, the first and second target paths that take into account the complex behavior specific to articulated vehicles from the parking start position to the parking target position are obtained.

[0012] The parking path generation device further comprises a vehicle body trajectory prediction unit which predicts the passing trajectory of the trailer body based on the first target path and the second target path, and which predicts the passing trajectory of the tractor body based on the movement path, and a contact determination unit which determines whether the body will come into contact with an obstacle present in the vicinity of the combination vehicle based on the surrounding environment of the combination vehicle detected by the environment detection unit and the passing trajectory of the body predicted by the vehicle body trajectory prediction unit, and the turn back position setting unit may reset the turn back position when the contact determination unit determines that the combination vehicle will come into contact with an obstacle.

[0013] In this configuration, if there is a possibility that the combination vehicle will come into contact with an obstacle in the vicinity, the turning back position of the combination vehicle is reset, and therefore the first target route and the second target route are reliably generated so as to avoid contact with obstacles in the vicinity of the combination vehicle.

[0014] The parking path generation device may further include a coupling angle detection unit which detects the coupling angle between the tractor and the trailer, and the parking start position acquisition unit acquires the position coordinates, azimuth angle and turning curvature of the trailer as the parking start position based on the current position and coupling angle of the articulated vehicle, the parking target position setting unit sets the position coordinates, azimuth angle and turning curvature of the trailer as the parking target position based on information including the current position of the articulated vehicle and the coupling angle, and the turn position setting unit sets the position coordinates, azimuth angle and turning curvature of the trailer as the turn position based on the parking start position, the parking target position, the surrounding environment of the articulated vehicle and the coupling angle.

[0015] In this configuration, the trailer's position coordinates, azimuth angle, and turning curvature are obtained as the parking start position, parking target position, and turning back position of the articulated vehicle. Therefore, for example, a tri-clothoid curve, which has a low calculation load, can be used as the curve that forms the first target path and the second target path of the trailer.

[0016] Another aspect of the present invention is a parking control device for parking an articulated vehicle equipped with a tractor and a trailer, comprising: a position detection unit for detecting the current position of the articulated vehicle; an environment detection unit for detecting the surrounding environment of the articulated vehicle; a parking start position acquisition unit for acquiring a parking start position of the articulated vehicle using the current position of the articulated vehicle detected by the position detection unit; a parking target position setting unit for setting a parking target position of the articulated vehicle using information including the current position of the articulated vehicle detected by the position detection unit; a turn position setting unit for setting a turn position of the articulated vehicle using the parking start position acquired by the parking start position acquisition unit, the parking target position set by the parking target position setting unit, and the surrounding environment of the articulated vehicle detected by the environment detection unit; a target path generation unit that generates a first target path for the trailer from the parking start position to the turn around position and a second target path for the trailer from the turn around position to the parking target position based on the first target path and the second target path generated by the target path generation unit; a movement path calculation unit that calculates a movement path of the tractor based on the first target path and the second target path generated by the target path generation unit; and a following control unit that performs steering control of the tractor so as to park the articulated vehicle at the parking target position along the first target path and the second target path generated by the target path generation unit and the movement path calculated by the movement path calculation unit, wherein the target path generation unit generates, as the first target path, a geometric path having a curved portion whose curvature changes continuously from the parking start position to the turn around position, and generates, as the second target path, a geometric path having a curved portion whose curvature changes continuously from the turn around position to the parking target position.

[0017] In such a parking control device, the parking start position of the articulated vehicle is acquired using the current position of the articulated vehicle, and the parking target position of the articulated vehicle is set using information including the current position of the articulated vehicle. In addition, the turning position of the articulated vehicle is set using the parking start position and parking target position of the articulated vehicle and the surrounding environment of the articulated vehicle. At this time, the turning position is set so that the articulated vehicle does not come into contact with obstacles present in the vicinity, taking into account the surrounding environment of the articulated vehicle. Then, based on the parking start position, parking target position and turning position of the articulated vehicle, a first target path of the trailer from the parking start position to the turning position and a second target path of the trailer from the turning position to the parking target position are generated. Then, based on the first target path and the second target path of the trailer, the movement path of the tractor is calculated. Then, the steering control of the articulated vehicle is performed so that the articulated vehicle is parked at the parking target position along the first target path and the second target path of the trailer and the movement path of the tractor. Here, a geometric path having a curved portion whose curvature changes continuously between the parking start position and the turning position is generated as the first target path of the trailer. A geometric path having a curved portion with a continuously changing curvature between the turning position and the parking target position is generated as the second target path for the trailer. Therefore, smooth first and second target paths are generated from the parking start position to the parking target position, taking into account the attitude of the articulated vehicle. This allows a parking path that includes forward and backward turning, to be easily generated according to the actual environment.

[0018] The parking control device may further include a data series calculation unit that uses a geometric model of the articulated vehicle to perform a vehicle motion simulation in which the articulated vehicle is controlled to follow forward movement from the parking start position and the parking target position to the turn around position, after the movement path of the tractor is calculated by the movement path calculation unit, and calculates a data series of the steering angle of the tractor and a data series of each of the attitude angles of the tractor and the trailer, and the following control unit may perform steering control of the tractor so as to park the articulated vehicle at the parking target position in accordance with the data series of the steering angle of the tractor and the data series of each of the attitude angles of the tractor and the trailer calculated by the data series calculation unit.

[0019] In such a configuration, a vehicle motion simulation is performed in which the articulated vehicle is controlled to follow forward travel from the parking start position and the parking target position to the turn-around position, respectively, to calculate a data series of the steering angle of the tractor and a data series of the attitude angles of the tractor and trailer that ensure a stable coupling angle. Also, when parking the articulated vehicle at the parking target position, the steering control of the tractor is performed in accordance with the data series of the steering angle of the tractor and the data series of the attitude angles of the tractor and trailer, thereby making it possible to guide the articulated vehicle along the parking path to the parking target position with high accuracy.

[0020] The parking control device may further include a coupling angle detection unit which detects the coupling angle between the tractor and the trailer, and the tracking control unit may perform feedforward control of the steering of the tractor so as to park the articulated vehicle at the parking target position in accordance with the data series of the steering angle of the tractor and the data series of the attitude angles of the tractor and the trailer, and may also perform feedback control of the steering of the tractor so as to park the articulated vehicle at the parking target position based on the coupling angle and the current position of the articulated vehicle.

[0021] With this configuration, not only is feedforward control of the tractor steering performed in accordance with the data series of the tractor steering angle and the data series of each of the tractor and trailer attitude angles, but feedback control of the tractor steering is also performed based on the coupling angle between the tractor and trailer and the current position of the combination vehicle, making it possible to accurately guide the combination vehicle along the parking path to the parking target position even in the event of external disturbances, etc. Effect of the Invention

[0022] According to the present invention, a parking path that includes forward and reverse turns can be easily generated in accordance with the actual environment. [Brief description of the drawings]

[0023] [Figure 1] 1 is a block diagram illustrating a parking control device including a parking path generation device according to an embodiment of the present invention. [Diagram 2]2 is a side view of an articulated vehicle equipped with the parking control device shown in FIG. 1. [Diagram 3] 3 is a plan view showing how the articulated vehicle shown in FIG. 2 is parked. FIG. [Figure 4] 2 is a flowchart showing details of a procedure of a route generation process executed by a route generation ECU shown in FIG. 1. [Diagram 5] FIG. 3 is a schematic diagram showing a model of the combination vehicle shown in FIG. 2. [Figure 6] 4 is a plan view showing a first target route of the trailer from the parking start position to the turning position and a second target route of the trailer from the turning position to the parking target position. FIG. [Figure 7] This is a graph showing an example of a second target path for the trailer obtained by a tri-clothoid curve, together with the tractor's movement path. [Figure 8] 1 is a graph showing an example of passing trajectories of a trailer body and a tractor body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0025] Fig. 1 is a block diagram showing a schematic diagram of a parking control device equipped with a parking path generating device according to an embodiment of the present invention. In Fig. 1, the parking control device 1 of this embodiment is a device that automatically parks an articulated vehicle 2 in a parking lot or the like, as shown in Figs. 2 and 3.

[0026] The combination vehicle 2 here is a large semi-trailer truck. However, the combination vehicle 2 may be a medium-sized truck or a small truck. The combination vehicle 2 includes a tractor 3 and a trailer 4 arranged behind the tractor 3. The trailer 4 is rotatably connected to the tractor 3 at a connecting portion 5.

[0027] The tractor 3 has a body 6, a pair of left and right front wheels 7 rotatably supported on the front side of the body 6, and a pair of left and right rear wheels 8 rotatably supported on the rear side of the body 6. An engine (not shown) is mounted on the tractor 3. The trailer 4 has a body 9 and a pair of left and right wheels 10 rotatably supported on the rear side of the body 9.

[0028] Returning to FIG. 1, the parking control device 1 is mounted on an articulated vehicle 2. The parking control device 1 includes a car navigation system 11, an articulation angle sensor 12, a camera 13, a route generation ECU 14, and a parking control ECU15.

[0029] The car navigation 11, the articulated angle sensor 12, the camera 13, and the path generation ECU 14 constitute a parking path generation device 16 of this embodiment. The parking path generation device 16 is a device that generates a parking path for parking the articulated vehicle 2 by the parking control device 1.

[0030] As shown in Fig. 3, the parking path generating device 16 generates a parking path such that the vehicle advances from the side of the parking space H, turns around once, and then retreats to the parking space H. Specifically, the parking path generating device 16 generates a parking path such that the vehicle advances from the parking start position A1 to the turning position A3, and then retreats from the turning position A3 to the parking target position A2. The parking start position A1, the parking target position A2, and the turning position A3 will be described in detail later.

[0031] The car navigation system 11 comprises a GPS receiver 17 which receives radio waves transmitted from GPS satellites and measures the current position of the combination vehicle 2, a map storage unit 18 which stores map data, a display 19 which shows the current position of the combination vehicle 2 together with the map, and an input unit 20 which sets and inputs data such as the destination of the combination vehicle 2.

[0032] The GPS receiver 17 constitutes a position detection unit that detects the current position of the combination vehicle 2. The GPS receiver 17 detects the position coordinates in two-dimensional coordinates (X, Y coordinates) of the tractor 3 and the azimuth angle as the current position of the combination vehicle 2.

[0033] The coupling angle sensor 12 is a sensor (coupling angle detection unit) that detects the coupling angle θ (see FIG. 5) between the tractor 3 and the trailer 4. The coupling angle θ is the angle at which an imaginary line L1 extending in the fore-aft direction of the tractor 3 intersects with an imaginary line L2 extending in the fore-aft direction of the trailer 4. When the tractor 3 and the trailer 4 are arranged on the same straight line, the coupling angle θ is 0 degrees.

[0034] The camera 13 is an imaging unit that captures images of the surroundings of the combination vehicle 2. The cameras 13 are provided, for example, on the tractor 3 and the trailer 4. The camera 13 constitutes an environment detection unit that detects the surrounding environment of the combination vehicle 2, such as the presence or absence of obstacles 50 (see Figures 3 and 6).

[0035] The obstacles 50 include other parked vehicles 51 (see FIG. 3), building walls 52 (see FIG. 6), curbs, etc. When the building walls 52 can be identified from the map data built into the car navigation system 11, the map storage unit 18 of the car navigation system 11 also constitutes the environment detection unit.

[0036] The route generation ECU 14 is composed of a CPU, RAM, ROM, an input / output interface, etc. The route generation ECU 14 receives information from the car navigation system 11, detection values ​​from the articulated angle sensor 12, and images captured by the camera 13, executes processing related to generating a parking route for the articulated vehicle 2, and outputs data including the parking route for the articulated vehicle 2 to the parking control ECU 15.

[0037] The path generation ECU 14 has a parking start position acquisition unit 21, a parking target position setting unit 22, a turning position setting unit 23, a target path generation unit 24, a curvature constraint determination unit 25, a movement path calculation unit 26, a vehicle body trajectory prediction unit 27, a contact determination unit 28, a data series calculation unit 29, and a data output unit 30.

[0038] The parking start position acquisition unit 21 acquires the parking start position A1 (see FIG. 3) of the combination vehicle 2 using the current position of the combination vehicle 2 detected by the GPS receiver 17 of the car navigation system 11. Specifically, the parking start position acquisition unit 21 acquires the parking start position A1 of the combination vehicle 2 based on the current position of the combination vehicle 2 and the coupling angle θ between the tractor 3 and the trailer 4 detected by the coupling angle sensor 12. The parking start position acquisition unit 21 acquires the position coordinates, azimuth angle and turning curvature of the trailer 4 as the parking start position A1 of the combination vehicle 2.

[0039] The parking target position setting unit 22 sets the parking target position A2 (see FIG. 3) for the combination vehicle 2 using information from the car navigation system 11 including the current position of the combination vehicle 2 detected by the GPS receiver 17. Specifically, the parking target position setting unit 22 sets the parking target position A2 for the combination vehicle 2 based on information from the car navigation system 11 including the current position of the combination vehicle 2, the coupling angle θ between the tractor 3 and the trailer 4 detected by the coupling angle sensor 12, and the image captured by the camera 13. The parking target position setting unit 22 acquires the position coordinates, azimuth angle, and turning curvature of the trailer 4 as the parking target position A2 for the combination vehicle 2.

[0040] The turn-back position setting unit 23 sets a turn-back position A3 (see FIG. 3) of the combination vehicle 2 using the parking start position A1 of the combination vehicle 2 acquired by the parking start position acquisition unit 21, the parking target position A2 of the combination vehicle 2 set by the parking target position setting unit 22, and the surrounding environment of the combination vehicle 2 detected by the camera 13. Specifically, the turn-back position setting unit 23 sets the turn-back position A3 of the combination vehicle 2 based on the parking start position A1 and parking target position A2 of the combination vehicle 2, the coupling angle θ between the tractor 3 and the trailer 4 detected by the coupling angle sensor 12, and the image captured by the camera 13. The turn-back position A3 is a position where forward movement is switched to reverse. The turn-back position setting unit 23 acquires the position coordinates, azimuth angle, and turning curvature of the trailer 4 as the turn-back position A3 of the combination vehicle 2.

[0041] The target route generating unit 24 generates a first target route R1 and a second target route R2 (see FIG. 6) for the trailer 4 based on the parking start position A1 of the articulated vehicle 2 acquired by the parking start position acquiring unit 21, the parking target position A2 of the articulated vehicle 2 set by the parking target position setting unit 22, and the turning position A3 of the articulated vehicle 2 set by the turning position setting unit 23. The first target route R1 is a target route for the trailer 4 from the parking start position A1 to the turning position A3. The second target route R2 is a target route for the trailer 4 from the turning position A3 to the parking target position A2.

[0042] The target path generating unit 24 generates, as a first target path R1 for the trailer 4, a geometric path having a curved portion whose curvature changes continuously between the parking start position A1 and the turning back position A3 of the articulated vehicle 2. The target path generating unit 24 generates, as a second target path R2 for the trailer 4, a geometric path having a curved portion whose curvature changes continuously between the turning back position A3 and the parking target position A2 of the articulated vehicle 2.

[0043] The curvature constraint determination unit 25 determines whether the geometric routes, which are the first target route R1 and the second target route R2 of the trailer 4 generated by the target route generation unit 24, satisfy the constraint on the maximum turning curvature of the trailer 4 based on the vehicle structure. Specifically, the curvature constraint determination unit 25 determines whether the maximum curvature of the geometric routes, which are the first target route R1 and the second target route R2 of the trailer 4, is equal to or less than the maximum turning curvature of the trailer 4.

[0044] When the curvature constraint determination unit 25 determines that the maximum curvature of the geometric path is equal to or less than the maximum turning curvature of the trailer 4, the movement path calculation unit 26 calculates the movement path Q of the tractor 3 from the parking start position A1 to the parking target position A2 of the articulated vehicle 2, based on the first target path R1 and second target path R2 of the trailer 4 generated by the target path generation unit 24.

[0045] The vehicle body trajectory prediction unit 27 predicts the passing trajectory of the body 9 of the trailer 4 based on the first target path R1 and the second target path R2 of the trailer 4 generated by the target path generation unit 24, and also predicts the passing trajectory of the body 6 of the tractor 3 based on the movement path Q of the tractor 3 calculated by the movement path calculation unit 26.

[0046] The contact determination unit 28 determines whether the vehicle bodies 6, 9 will come into contact with an obstacle 50 (see Figs. 3 and 6) based on the information from the car navigation system 11, the image captured by the camera 13, and the passing trajectories of the body 9 of the trailer 4 and the body 6 of the tractor 3 predicted by the vehicle body trajectory prediction unit 27. The information from the car navigation system 11 and the image captured by the camera 13 correspond to detection data from the environment detection unit.

[0047] After the movement path Q of the tractor 3 is calculated by the movement path calculation unit 26, the data series calculation unit 29 uses a geometric model of the articulated vehicle 2 to perform a vehicle motion simulation in which the articulated vehicle 2 is controlled to follow the vehicle while traveling forward from the parking start position A1 and the parking target position A2 to the turning back position A3, thereby calculating a data series of the steering angle of the tractor 3 and a data series of each attitude angle of the tractor 3 and the trailer 4. Note that the data series is history data.

[0048] When the contact determination unit 28 determines that the vehicle bodies 6, 9 will not come into contact with the obstacle 50, the data output unit 30 outputs the first target path R1 and the second target path R2 of the trailer 4 and the movement path Q of the tractor 3 to the parking control ECU 15 as parking path data, and also outputs a data series of the steering angle of the tractor 3 and a data series of each attitude angle of the tractor 3 and the trailer 4 to the parking control ECU 15.

[0049] 4 is a flowchart showing the details of the procedure of the route generation process executed by the route generation ECU 14. This process is executed when the driver of the combination vehicle 2 issues a command to start parking assistance. At this time, the driver may set and input a parking target position candidate for the combination vehicle 2 via the input unit 20 of the car navigation system 11.

[0050] In FIG. 4, the route generation ECU 14 first acquires the position coordinates, azimuth angle and turning curvature of the trailer 4 as the parking start position A1 of the articulated vehicle 2 based on information from the car navigation 11 including the GPS receiver 17 and the detection value of the articulated angle sensor 12 (step S101).

[0051] The position coordinates of the trailer 4 are, for example, the position coordinates (X2, Y2) of the rear axle center O2 of the trailer 4, as shown in Fig. 5. The rear axle center O2 of the trailer 4 is the center in the axial direction (the width direction of the trailer 4) of the axles 10a connected to a pair of left and right wheels 10 arranged at the rear of the trailer 4, as shown in Fig. 3. The azimuth angle of the trailer 4 corresponds to the yaw angle Ψ2 of the trailer 4. The azimuth angle of the tractor 3 corresponds to the yaw angle Ψ1 of the tractor 3.

[0052] Furthermore, under conditions assuming steady turning of the combination vehicle 2, the turning curvature of the trailer 4 uniquely corresponds to the connection angle of the trailer 4 with respect to the tractor 3. For this reason, the connection angle θ between the tractor 3 and the trailer 4 can be found by an algebraic formula that uses the turning curvature of the trailer 4 as an input. Therefore, the turning curvature of the trailer 4 can be obtained from the connection angle θ between the tractor 3 and the trailer 4. When the connection angle θ between the tractor 3 and the trailer 4 is 0 degrees, the turning curvature of the trailer 4 is 0. Note that FIG. 5 shows a model of the combination vehicle 2.

[0053] Next, the route generation ECU 14 sets the position coordinates, azimuth angle and turning curvature of the trailer 4 as the parking target position A2 of the combination vehicle 2 based on information from the car navigation system 11 including the GPS receiver 17, the detection value of the combination angle sensor 12 and the image captured by the camera 13 (step S102).

[0054] Next, the route generation ECU 14 sets the position coordinates, azimuth angle and turning curvature of the trailer 4 as the turning position A3 of the combination vehicle 2 based on the parking start position A1 and parking target position A2 of the combination vehicle 2, the detection value of the combination angle sensor 12 and the image captured by the camera 13 (step S103). At this time, the route generation ECU 14 calculates areas that are candidates for the turning position A3 of the combination vehicle 2 from the parking start position A1 and parking target position A2 of the combination vehicle 2, and sets the turning position A3 within that area so as not to come into contact with the obstacle 50.

[0055] Next, the path generation ECU 14 generates a first target path R1 and a second target path R2 for the rear axle center O2 of the trailer 4 based on the parking start position A1, the parking target position A2, and the turning-back position A3 of the articulated vehicle 2 (step S104). The first target path R1 for the rear axle center O2 of the trailer 4 is a geometric path having a curved portion whose curvature changes continuously between the parking start position A1 and the turning-back position A3 of the articulated vehicle 2, as shown in Fig. 6. The second target path R2 for the rear axle center O2 of the trailer 4 is a geometric path having a curved portion whose curvature changes continuously between the turning-back position A3 and the parking target position A2 of the articulated vehicle 2, as shown in Fig. 6. A tri-clothoid curve is used as the curve whose curvature changes continuously.

[0056] A tri-clothoid curve is a curve in which the curvature does not change suddenly. For example, a tri-clothoid curve is a curve in which the rate of change of curvature is constant. A tri-clothoid curve is a smooth curve in which the initial and terminal curves and positions can be arbitrarily specified by combining three clothoid curves with equal path lengths. A tri-clothoid curve can be easily obtained by numerically solving a nonlinear equation with two variables. For details on tri-clothoid curves, see "Path Generation Method Using Clothoid Curves with Specifiable Initial and Terminal Curvatures" in Transactions of the Japan Society of Mechanical Engineers (Vol. 85, No. 878, 2019).

[0057] Fig. 7 is a graph showing an example of the second target path R2 of the rear axle center O2 of the trailer 4 obtained by a tri-clothoid curve. Note that Fig. 7 shows the results of a simulation of path generation for a semi-trailer type articulated vehicle.

[0058] In FIG. 7, one end of the second target route R2 of the trailer 4 given by a tri-clothoid curve represents the position of the trailer 4 at the turning back position A3 of the articulated vehicle 2. The other end of the second target route R given by a tri-clothoid curve represents the position of the trailer 4 at the parking target position A2 of the articulated vehicle 2. At the turning back position A3, the position coordinates are (Xa, Ya), the azimuth angle is 0 degrees, and the turning curvature is 0. At the parking target position A2, the position coordinates are (Xb, Yb), the azimuth angle is 90 degrees, and the turning curvature is 0. In addition, the end of the second target route R2 on the parking target position A2 side is a straight line, and the other part of the second target route R2 is a curved section. The second target route R2 may be curved overall.

[0059] Next, the path generation ECU 14 judges whether the maximum curvature of the geometric path, which is the first target path R1 and the second target path R2 of the rear axle center O2 of the trailer 4, is equal to or less than the maximum turning curvature of the trailer 4 (step S105). The maximum turning curvature of the trailer 4 is determined in advance according to the maximum steering angle and maximum coupling angle of the vehicle structure of the combination vehicle 2. The steering angle of the combination vehicle 2 is the steering angle δ of the front wheels 7 of the tractor 3 (see FIG. 5).

[0060] When the path generation ECU 14 determines that the maximum curvature of the geometric paths, which are the first target path R1 and the second target path R2 of the rear axle center O2 of the trailer 4, is not less than the maximum turning curvature of the trailer 4, it executes the above-mentioned step S103 again and resets the turning back position A3 of the combination vehicle 2.

[0061] When the path generation ECU 14 determines that the maximum curvature of the geometric paths, which are the first target path R1 and the second target path R2 of the rear axle center O2 of the trailer 4, is less than or equal to the maximum turning curvature of the trailer 4, it calculates the movement path Q of the rear axle center O1 of the tractor 3 based on the first target path R1 and the second target path R2 of the rear axle center O2 of the trailer 4 and the dimensions of the body 9 of the trailer 4 (step S106).

[0062] At this time, the path generation ECU 14, assuming steady turning of the combination vehicle 2, determines the coupling angle θ between the tractor 3 and the trailer 4 using an algebraic formula from the curvatures of the first target path R1 and the second target path R2 of the rear axle center O2 of the trailer 4, and determines the movement path Q of the rear axle center O1 of the tractor 3 algebraically from the relative relationship with the position of the trailer 4. Since values ​​with continuously changing curvature are used as the geometric paths that are the first target path R1 and the second target path R2 of the rear axle center O2 of the trailer 4, it is acceptable to determine the coupling angle θ assuming steady turning of the combination vehicle 2, and the obtained coupling angle θ is also a value that continuously changes. Therefore, the smooth relative behavior of the trailer 4 and the tractor 3 is approximately expressed without solving the complex combination vehicle dynamics that are generally expressed by differential equations.

[0063] As shown in Fig. 3, the rear axle center O1 of the tractor 3 is the center in the axial direction (the vehicle width direction of the tractor 3) of an axle 8a connected to a pair of left and right rear wheels 8 of the tractor 3. An axle 7a is connected to a pair of left and right front wheels 7 of the tractor 3. The position coordinates of the rear axle center O1 of the tractor 3 are (X1, Y1) (see Fig. 5).

[0064] In the simulation shown in Fig. 7, the movement path Q of the rear axle center O1 of the tractor 3 is obtained from the second target path R2 of the rear axle center O2 of the trailer 4, which is given by a tri-clothoid curve. The movement path Q is a characteristic curve according to the second target path R2 of the rear axle center O2 of the trailer 4.

[0065] Next, the path generation ECU 14 predicts the passing trajectory of the body 9 of the trailer 4 based on the first target path R1 and the second target path R2 of the rear axle center O2 of the trailer 4 and the shape and dimensions of the body 9 of the trailer 4, and also predicts the passing trajectory of the body 6 of the tractor 3 based on the movement path Q of the rear axle center O1 of the tractor 3 and the shape and dimensions of the body 6 of the tractor 3 (step S107).

[0066] Fig. 8 is a graph showing an example of the passing trajectories of the body 9 of the trailer 4 and the body 6 of the tractor 3, and corresponds to the graph shown in Fig. 7. In Fig. 8, the passing trajectory B1 of the body 9 of the trailer 4 is geometrically determined based on the second target path R2 of the rear axle center O2 of the trailer 4 shown in Fig. 7. The passing trajectory B2 of the body 6 of the tractor 3 is geometrically determined based on the movement path Q of the rear axle center O1 of the tractor 3 shown in Fig. 7.

[0067] Next, the route generation ECU 14 judges whether or not the bodies 6, 9 of the combination vehicle 2 will come into contact with a surrounding obstacle 50 (see FIG. 6) based on the information from the car navigation 11 and the images captured by the camera 13 (step S108). If the route generation ECU 14 judges that the bodies 6, 9 of the combination vehicle 2 will come into contact with a surrounding obstacle 50, it executes the above step S103 again and resets the turning back position A3 for the combination vehicle 2.

[0068] When the path generation ECU 14 determines that the vehicle bodies 6, 9 of the articulated vehicle 2 will not come into contact with the surrounding obstacles 50, the path generation ECU 14 uses a simplified geometric model of the articulated vehicle 2 to perform forward tracking control of the articulated vehicle 2 from the parking start position A1 to the turning back position A3 along the first target route R1 and the moving route Q, and performs a vehicle motion simulation to perform forward tracking control of the articulated vehicle 2 from the parking target position A2 to the turning back position A3 along the second target route R2 and the moving route Q, thereby calculating a data series of the steering angle of the tractor 3 and a data series of each attitude angle of the tractor 3 and the trailer 4 (step S109). The steering angle of the tractor 3 corresponds to the steering angle δ of the front wheels 7 of the tractor 3. At this time, the path generation ECU 14 may perform a vehicle motion simulation to perform tracking control using a path tracking control method for the geometric route that is the moving route Q of the tractor 3, for example.

[0069] In actual parking, the articulated vehicle 2 is reversed from the turning back position A3 to the parking target position A2. However, a power source such as an engine is mounted on the tractor 3, not on the trailer 4. Therefore, when the articulated vehicle 2 is reversed, the tractor 3 pushes the trailer 4, and the behavior of the connection angle θ between the tractor 3 and the trailer 4 is unstable. For this reason, when performing tracking control, the adjustment of the numerical parameters of the controller is unavoidably complicated.

[0070] On the other hand, when the combination vehicle 2 is moved forward, the tractor 3 travels pulling the trailer 4, so the behavior of the coupling angle θ between the tractor 3 and the trailer 4 is stable. For this reason, the numerical parameters used in the tracking control can be set relatively easily. Also, in step S105 above, it is ensured that the maximum curvature of the geometric path, which is the target path, is equal to or less than the maximum turning value of the combination vehicle 2, so that in the vehicle motion simulation, even if the forward travel of the combination vehicle 2 is played back in reverse, the same trajectory as when the combination vehicle 2 is traveling forward can be obtained.

[0071] Therefore, in this vehicle motion simulation, a forward driving simulation is also performed between the turning position A3 and the parking target position A2, with the parking target position A2 as the starting point and the turning position A3 as the destination point.

[0072] Next, the path generation ECU 14 outputs the first target path R1 and the second target path R2 of the rear axle center O2 of the trailer 4 and the movement path Q of the rear axle center O1 of the tractor 3 as parking path data to the parking control ECU 15, and also outputs a data series of the steering angle of the tractor 3 and a data series of each attitude angle of the tractor 3 and the trailer 4 to the parking control ECU 15 (step S110).

[0073] Here, the parking start position acquisition unit 21 executes step S101. The parking target position setting unit 22 executes step S102. The turning back position setting unit 23 executes step S103. The target path generation unit 24 executes step S104. The curvature constraint determination unit 25 executes step S105. The movement path calculation unit 26 executes step S106. The vehicle body trajectory prediction unit 27 executes step S107. The contact determination unit 28 executes step S108. The data sequence calculation unit 29 executes step S109. The data output unit 30 executes step S110.

[0074] Returning to Fig. 1, the parking control ECU 15 is composed of a CPU, RAM, ROM, an input / output interface, etc. The parking control ECU 15 inputs parking route data and a data series from the route generation ECU 14, information from the car navigation system 11, and the detection value of the articulated vehicle angle sensor 12, and executes processing related to automatic parking of the articulated vehicle 2.

[0075] The parking control ECU 15 has a storage unit 31 and a following control unit 32. The storage unit 31 stores the parking path data and the data series output from the data output unit 30 of the path generation ECU 14.

[0076] The following control unit 32 performs steering control and speed control of the combination vehicle 2 so as to park the combination vehicle 2 at the parking target position A2 in accordance with the parking route data and data series stored in the memory unit 31. The following control unit 32 performs steering control and speed control of the combination vehicle 2 so as to make the combination vehicle 2 follow and travel along the movement route Q of the rear axle center O1 of the tractor 3 and the first target route R1 and second target route R2 of the rear axle center O2 of the trailer 4. The following control unit 32 controls the steering of the combination vehicle 2 in the steering control of the combination vehicle 2, and controls the accelerator and brake in the speed control of the combination vehicle 2.

[0077] At this time, the follow-up control unit 32 performs feedforward control of the steering of the tractor 3 so as to park the combination vehicle 2 at the parking target position A2, according to the data series of the steering angle of the tractor 3 and the data series of the attitude angles of the tractor 3 and the trailer 4. In other words, the follow-up control unit 32 performs feedforward control of the steering of the tractor 3, using the data series of the steering angle of the tractor 3 and the data series of the attitude angles of the tractor 3 and the trailer 4 as target values. In addition, the follow-up control unit 32 performs feedback control of the steering of the tractor 3 so as to park the combination vehicle 2 at the parking target position A2, based on the coupling angle θ between the tractor 3 and the trailer 4 detected by the coupling angle sensor 12 and the current position of the combination vehicle 2 detected by the GPS receiver 17.

[0078] The tracking control unit 32 considers a vehicle with a target posture virtually on a target path of the trailer 4 given by, for example, a tri-clothoid curve, and performs tracking control so as to bring the relative error of the actual vehicle with respect to the target value as a state quantity closer to 0. As a tracking control that brings the error state quantity closer to 0, for example, LQ control can be mentioned.

[0079] As described above, in this embodiment, the parking start position A1 of the combination vehicle 2 is acquired using the current position of the combination vehicle 2, and the parking target position A2 of the combination vehicle 2 is set using information including the current position of the combination vehicle 2. In addition, the turning position A3 of the combination vehicle 2 is set using the parking start position A1 and the parking target position A2 of the combination vehicle 2 and the surrounding environment of the combination vehicle 2. At this time, the turning position A3 is set so that the combination vehicle 2 does not come into contact with the obstacle 50 present in the vicinity, taking into consideration the surrounding environment of the combination vehicle 2. Then, based on the parking start position A1, the parking target position A2, and the turning position A3 of the combination vehicle 2, a first target route R1 of the trailer 4 from the parking start position A1 to the turning position A3 and a second target route R2 of the trailer 4 from the turning position A3 to the parking target position A2 are generated. Then, based on the first target route R1 and the second target route R2 of the trailer 4, the movement route Q of the tractor 3 is calculated. Then, the articulated vehicle 2 is steered to park the articulated vehicle 2 at the parking target position A2 along the first target path R1 and the second target path R2 of the trailer 4 and the moving path Q of the tractor 3. Here, as the first target path R1 of the trailer 4, a geometric path having a curved portion whose curvature changes continuously between the parking start position A1 and the turning position A3 of the articulated vehicle 2 is generated. As the second target path R2 of the trailer 4, a geometric path having a curved portion whose curvature changes continuously between the turning position A3 and the parking target position A2 of the articulated vehicle 2 is generated. Therefore, taking into consideration the attitude of the articulated vehicle 2, the first target path R1 and the second target path R2 are generated that are smooth from the parking start position A1 to the parking target position A2. As a result, a parking path that includes turning back between forward and backward is easily generated according to the actual environment. In addition, because there is no need for prior offline calculation according to the vehicle parameters, it is easy to respond to changes in the vehicle parameters, such as changing the connection of the trailer 4. As a result, it is possible to realize introduction to mass-produced vehicles at low cost.

[0080] Furthermore, in this embodiment, a smooth parking path is generated from the parking start position A1 of the articulated vehicle 2 to the parking target position A2. By combining such a parking path with steering control that utilizes, for example, the path curvature as feedforward information, it is possible to realize path following control that reduces the deviation of the articulated vehicle 2 from the parking path. Furthermore, for example, by substituting the values ​​of the first target path R1 and the second target path R2 of the trailer 4 into an algebraic formula, it is possible to easily predict the passing trajectories of the body 9 of the trailer 4 and the body 6 of the tractor 3. Therefore, it is possible to generate a parking path that avoids contact with the obstacles 50 present around the articulated vehicle 2 while simplifying the calculation process.

[0081] Furthermore, in this embodiment, a vehicle motion simulation is performed using a geometric model of the articulated vehicle 2 to perform forward tracking control of the articulated vehicle 2 from the parking start position A1 and the parking target position A2 to the turning back position A3, thereby making it possible to calculate a data series of the steering angle of the tractor 3 and a data series of the attitude angles of the tractor 3 and the trailer 4 that ensure stability of the coupling angle θ. Furthermore, when parking the articulated vehicle 2 at the parking target position A2, the steering control of the tractor 3 is performed in accordance with the data series of the steering angle of the tractor 3 and the data series of the attitude angles of the tractor 3 and the trailer 4, thereby making it possible to accurately guide the articulated vehicle 2 along the parking path to the parking target position A2.

[0082] Furthermore, in this embodiment, not only is feedforward control of the steering of the tractor 3 performed in accordance with the data series of the steering angle of the tractor 3 and the data series of each attitude angle of the tractor 3 and the trailer 4, but feedback control of the steering of the tractor 3 is performed based on the coupling angle θ between the tractor 3 and the trailer 4 and the current position of the combination vehicle 2, so that the combination vehicle 2 can be guided with high accuracy along the parking path to the parking target position A2 even in the event of external disturbances, etc.

[0083] In this embodiment, when it is determined that the maximum curvature of the geometric routes, which are the first target route R1 and the second target route R2 of the trailer 4, is equal to or less than the maximum turning curvature of the trailer 4, the moving route Q of the tractor 3 is calculated, and when it is determined that the maximum curvature of the geometric route is not equal to or less than the maximum turning curvature of the trailer 4, the turning position A3 of the combination vehicle 2 is reset. Therefore, the maximum curvature of the geometric routes, which are the first target route R1 and the second target route R2 of the trailer 4, is equal to or less than the maximum turning curvature of the trailer 4, which is determined by the maximum steering angle of the tractor 3 and the maximum coupling angle between the tractor 3 and the trailer 4. Therefore, the first target route R1 and the second target route R2 are obtained from the parking start position A1 to the parking target position A2, taking into consideration the complex behavior specific to the combination vehicle 2.

[0084] Furthermore, in this embodiment, the passing trajectory of the body 9 of the trailer 4 is predicted based on the first target route R1 and the second target route R2 of the trailer 4, and the passing trajectory of the body 6 of the tractor 3 is predicted based on the movement route Q of the tractor 3. Then, based on the image captured by the camera 13 and the passing trajectories of the bodies 6, 9, it is determined whether the bodies 6, 9 will come into contact with an obstacle 50, and if it is determined that the bodies 6, 9 will come into contact with the obstacle 50, the turning back position A3 of the combination vehicle 2 is reset. Therefore, the first target route R1 and the second target route R2 are reliably generated so as to avoid contact with the obstacles 50 present around the combination vehicle 2.

[0085] In this embodiment, the position coordinates, azimuth angle and turning curvature of the trailer 4 are obtained as the parking start position A1, parking target position A2 and turning position A3 of the combination vehicle 2. Therefore, as the curves forming the first target route R1 and the second target route R2 of the trailer 4, for example, a tri-clothoid curve or the like with a low calculation load can be adopted.

[0086] The present invention is not limited to the above embodiment. For example, in the above embodiment, the current position of the combination vehicle 2 is measured by the GPS receiver 17 of the car navigation system 11, but the position detection unit that detects the current position of the combination vehicle 2 is not particularly limited to the GPS receiver 17. For example, the current position of the combination vehicle 2 may be estimated using a laser SLAM method that uses data from a laser sensor that irradiates a laser around the combination vehicle 2 and receives the reflected laser light, or the current position of the combination vehicle 2 may be estimated using a visual SLAM method that uses an image captured by a camera.

[0087] Further, in the above embodiment, the camera 13 is used to detect the surrounding environment of the combination vehicle 2, however, this is not particularly limited to this form, and a laser sensor, radar sensor, etc. may be used instead of or together with the camera 13 to detect the surrounding environment of the combination vehicle 2.

[0088] In addition, in the above embodiment, the first target path R1 and the second target path R2 of the rear axle center O2 of the trailer 4 are generated, and the movement path Q of the rear axle center O1 of the tractor 3 is calculated, but the present invention is not limited to such an embodiment. As the first target path R1 and the second target path R2 of the trailer 4, target paths of an arbitrary point of the trailer 4 (for example, the center point of the body 9) may be generated. As the movement path Q of the tractor 3, the movement path of an arbitrary point of the tractor 3 (for example, the center point of the body 6) may be calculated.

[0089] In the above embodiment, the first target route R1 and the second target route R2 of the trailer 4 are generated by using a tri-clothoid curve, but the present invention is not limited to this form. The first target route R1 of the trailer 4 may be a curve whose curvature changes continuously between the parking start position A1 and the turning position A3 of the articulated vehicle 2. The second target route R2 of the trailer 4 may be a curve whose curvature changes continuously between the turning position A3 and the parking target position A2 of the articulated vehicle 2. Examples of such curves include a Biarc curve, a Clothoid curve, a Bezier curve, and a Spline curve.

[0090] Furthermore, in the above embodiment, when it is determined that the maximum curvature of the geometric paths, which are the first target path R1 and the second target path R2 of the trailer 4, is not equal to or less than the maximum turning curvature of the trailer 4, or when it is determined that the articulated vehicle 2 will come into contact with an obstacle 50 present in the vicinity, the turn-back position A3 of the articulated vehicle 2 is reset; however, if the conditions of the judgment constraint are not satisfied even after the resetting of the turn-back position A3 has been repeated a certain number of times, it may be determined that it is not possible to guide the articulated vehicle 2 to the given parking target position A2, and the driver may be notified to change the parking target position A2 or the parking start position A1.

[0091] In the above embodiment, the turn-back position A3 of the articulated vehicle 2 is reset when it is determined that the maximum curvature of the geometric routes, that is, the first target route R1 and the second target route R2 of the trailer 4, is not equal to or less than the maximum turning curvature of the trailer 4, but the parking target position A2 may be reset together with the turn-back position A3. The same applies when it is determined that the articulated vehicle 2 will come into contact with an obstacle 50 present in the vicinity.

[0092] In the above embodiment, the articulated vehicle 2 is a semi-trailer truck, but the present invention is also applicable to full-trailer trucks. The present invention is not particularly limited to trucks, and can also be applied to articulated vehicles such as buses.

[0093] Furthermore, the parking path generating device 16 in the above embodiment is provided in the parking control device 1 that parks the articulated vehicle 2 by automatic driving, but the present invention is not limited to this form in particular and can also be applied to cases where parking of the articulated vehicle 2 is performed by manual driving using a parking assistance system. [Explanation of symbols]

[0094] 1...parking control device, 2...articulated vehicle, 3...tractor, 4...trailer, 6...vehicle body, 9...vehicle body, 12...articulation angle sensor (articulation angle detection unit), 13...camera (environment detection unit), 16...parking path generation device, 17...GPS receiver (position detection unit), 21...parking start position acquisition unit, 22...parking target position setting unit, 23...turn position setting unit, 24...target path generation unit, 25...curvature constraint determination unit, 26...movement path calculation unit, 27...vehicle body trajectory prediction unit, 28...contact determination unit, 29...data series calculation unit, 32...following control unit, 50...obstacle, A1...parking start position, A2...parking target position, A3...turn position, R1...first target path, R2...second target path.

Claims

1. A parking path generating device that generates a parking path for parking a combination vehicle equipped with a tractor and a trailer, a position detection unit for detecting a current position of the combination vehicle; an environment detection unit that detects the surrounding environment of the combination vehicle; a parking start position acquisition unit that acquires a parking start position of the combination vehicle using the current position of the combination vehicle detected by the position detection unit; a parking target position setting unit that sets a parking target position of the combination vehicle by using information including the current position of the combination vehicle detected by the position detection unit; a turn-around position setting unit that sets a turn-around position of the combination vehicle by using the parking start position acquired by the parking start position acquisition unit, the parking target position set by the parking target position setting unit, and the surrounding environment of the combination vehicle detected by the environment detection unit; a target route generating unit that generates a first target route for the trailer from the parking start position to the turn position and a second target route for the trailer from the turn position to the parking target position based on the parking start position acquired by the parking start position acquiring unit, the parking target position set by the parking target position setting unit, and the turn position set by the turn position setting unit; a movement path calculation unit that calculates a movement path of the tractor based on the first target path and the second target path generated by the target path generation unit; a data series calculation unit that calculates a data series of the steering angle of the tractor and a data series of each attitude angle of the tractor and the trailer by implementing a vehicle motion simulation using a geometric model of the articulated vehicle to perform forward tracking control of the articulated vehicle from the parking start position and the parking target position to the turning back position after the movement path of the tractor has been calculated by the movement path calculation unit, The target route generation unit generates, as the first target route, a geometric route having a curved portion whose curvature changes continuously between the parking start position and the turning position, and generates, as the second target route, a geometric route having a curved portion whose curvature changes continuously between the turning position and the parking target position.

2. A parking path generating device that generates a parking path for parking a combination vehicle equipped with a tractor and a trailer, a position detection unit for detecting a current position of the combination vehicle; an environment detection unit that detects the surrounding environment of the combination vehicle; a parking start position acquisition unit that acquires a parking start position of the combination vehicle using the current position of the combination vehicle detected by the position detection unit; a parking target position setting unit that sets a parking target position of the combination vehicle by using information including the current position of the combination vehicle detected by the position detection unit; a turn-around position setting unit that sets a turn-around position of the combination vehicle by using the parking start position acquired by the parking start position acquisition unit, the parking target position set by the parking target position setting unit, and the surrounding environment of the combination vehicle detected by the environment detection unit; a target route generating unit that generates a first target route for the trailer from the parking start position to the turn position and a second target route for the trailer from the turn position to the parking target position based on the parking start position acquired by the parking start position acquiring unit, the parking target position set by the parking target position setting unit, and the turn position set by the turn position setting unit; a movement path calculation unit that calculates a movement path of the tractor based on the first target path and the second target path generated by the target path generation unit; a coupling angle detection unit that detects a coupling angle between the tractor and the trailer, the parking start position acquisition unit acquires position coordinates, an azimuth angle, and a turning curvature of the trailer as the parking start position based on the current position of the articulated vehicle and the articulation angle, the parking target position setting unit sets a position coordinate, an azimuth angle and a turning curvature of the trailer as the parking target position based on information including a current position of the articulated vehicle and the articulated angle; the turning-back position setting unit sets a position coordinate, an azimuth angle and a turning curvature of the trailer as the turning-back position based on the parking start position, the parking target position, the surrounding environment of the articulated vehicle, and the articulation angle; The target route generation unit generates, as the first target route, a geometric route having a curved portion whose curvature changes continuously between the parking start position and the turning position, and generates, as the second target route, a geometric route having a curved portion whose curvature changes continuously between the turning position and the parking target position.

3. a curvature constraint determination unit that determines whether a maximum curvature of a geometric path that is the first target path and the second target path is equal to or less than a maximum turning curvature of the trailer; the movement path calculation unit calculates a movement path of the tractor when the curvature constraint determination unit determines that the maximum curvature of the geometric path is equal to or less than the maximum turning curvature, 3. The parking path generating device according to claim 1, wherein the turn-back position setting unit resets the turn-back position when the curvature constraint determination unit determines that the maximum curvature of the geometric path is not equal to or less than the maximum turning curvature.

4. a vehicle body trajectory prediction unit that predicts a passing trajectory of the vehicle body of the trailer based on the first target route and the second target route, and predicts a passing trajectory of the vehicle body of the tractor based on the moving route; a contact determination unit that determines whether the vehicle body will come into contact with an obstacle present in the vicinity of the combination vehicle, based on the surrounding environment of the combination vehicle detected by the environment detection unit and the passing trajectory of the vehicle body predicted by the vehicle body trajectory prediction unit, 4. The parking path generating device according to claim 1, wherein the turning-back position setting unit resets the turning-back position when the contact determination unit determines that the articulated vehicle will contact the obstacle.

5. A parking control device for parking a combination vehicle having a tractor and a trailer, a position detection unit for detecting a current position of the combination vehicle; an environment detection unit that detects the surrounding environment of the combination vehicle; a parking start position acquisition unit that acquires a parking start position of the combination vehicle using the current position of the combination vehicle detected by the position detection unit; a parking target position setting unit that sets a parking target position of the combination vehicle by using information including the current position of the combination vehicle detected by the position detection unit; a turn-around position setting unit that sets a turn-around position of the combination vehicle by using the parking start position acquired by the parking start position acquisition unit, the parking target position set by the parking target position setting unit, and the surrounding environment of the combination vehicle detected by the environment detection unit; a target route generating unit that generates a first target route for the trailer from the parking start position to the turn position and a second target route for the trailer from the turn position to the parking target position based on the parking start position acquired by the parking start position acquiring unit, the parking target position set by the parking target position setting unit, and the turn position set by the turn position setting unit; a movement path calculation unit that calculates a movement path of the tractor based on the first target path and the second target path generated by the target path generation unit; a data series calculation unit that calculates a data series of the steering angle of the tractor and a data series of each attitude angle of the tractor and the trailer by implementing a vehicle motion simulation using a geometric model of the articulated vehicle to perform forward tracking control of the articulated vehicle from the parking start position and the parking target position to the turn around position after the movement path of the tractor has been calculated by the movement path calculation unit; a tracking control unit that performs steering control of the tractor so as to park the articulated vehicle at the parking target position along the first target route and the second target route generated by the target route generation unit and the movement route calculated by the movement route calculation unit, the target route generation unit generates, as the first target route, a geometric route having a curved portion whose curvature changes continuously between the parking start position and the turning position, and generates, as the second target route, a geometric route having a curved portion whose curvature changes continuously between the turning position and the parking target position; The following control unit is a parking control device that performs steering control of the tractor so as to park the articulated vehicle at the target parking position in accordance with the data series of the steering angle of the tractor and the data series of each attitude angle of the tractor and the trailer calculated by the data series calculation unit.

6. A coupling angle detection unit detects a coupling angle between the tractor and the trailer, 6. A parking control device according to claim 5, wherein the following control unit performs feedforward control of the steering of the tractor so as to park the combination vehicle at the parking target position in accordance with a data series of the steering angle of the tractor and a data series of each of the attitude angles of the tractor and the trailer, and performs feedback control of the steering of the tractor so as to park the combination vehicle at the parking target position based on the combination angle and a current position of the combination vehicle.

Images