Towing vehicle control device, towing vehicle control method, and computer-readable medium

Abstract

The present disclosure relates to a towing vehicle control device, a towing vehicle control method, and a computer-readable medium. The towing vehicle control device includes: an arithmetic device that calculates a target vehicle body speed and a target curvature of a towing vehicle from a target vehicle body speed and a target curvature of a towed vehicle that is able to travel together with the towing vehicle in a state in which the towing vehicle is linked to the towed vehicle by a link portion that is a universal joint, and generates a control signal for power of the towing vehicle based on a target fold angle that is a target value of a fold angle, the target vehicle body speed of the towing vehicle, and the target curvature of the towing vehicle, wherein the target fold angle is calculated based on the target curvature of the towed vehicle, and the fold angle is an angle formed by a traveling direction of the towing vehicle and a traveling direction of the towed vehicle; and a drive control portion that controls the power of the towing vehicle in accordance with the control signal.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a towing vehicle control device that controls a towing vehicle that tows a towed vehicle, a towing vehicle control method, and a computer-readable medium that records a towing vehicle control program. BACKGROUND

[0002] In a case where the towed vehicle is caused to follow the towing vehicle while being coupled to the rear of the towing vehicle, it is easy for the towed vehicle to undergo roll vibration and the like.

[0003] A travel control device of a vehicle is disclosed in Japanese Patent Application Publication No. 2019-156066, which stabilizes the behavior of the towed vehicle by reducing roll vibration that occurs in the towed vehicle.

[0004] However, the invention described in Japanese Patent Application Publication No. 2019-156066 corrects the steering of the towing vehicle based on the roll of the towed vehicle at the time of towing, but the correction does not take into account the travel trajectory of the towed vehicle, and thus there is a problem in that it is difficult to cause the towed vehicle to travel with an appropriate trajectory.

[0005] The present disclosure provides a towing vehicle control device, a towing vehicle control method, and a computer-readable medium that records a towing vehicle control program, which enable the towed vehicle to travel with an appropriate trajectory. SUMMARY

[0006] A first aspect of the present disclosure is a towing vehicle control device including: an arithmetic unit that calculates a target vehicle body speed and a target curvature of a towing vehicle from a target vehicle body speed and a target curvature of a towed vehicle that is capable of traveling together with the towing vehicle in a state of being coupled to the towing vehicle that has a power source via a coupling portion that is a universal joint, and generates a control signal of the power of the towing vehicle based on a target bend angle that is a target value of a bend angle, the target vehicle body speed of the towing vehicle, and the target curvature of the towing vehicle, wherein the target bend angle is calculated based on the target curvature of the towed vehicle, and the bend angle is an angle formed by a traveling direction of the towing vehicle and a traveling direction of the towed vehicle; and a drive control unit that controls the power of the towing vehicle in accordance with the control signal.

[0007] According to the towing vehicle control device of the first aspect, by calculating the control condition of the towing vehicle in a case where the towed vehicle turns with the target curvature, the towed vehicle can be caused to travel with an appropriate trajectory.

[0008] In some cases, for example, interference occurs between the towing vehicle and the towed vehicle, but the towing vehicle control device of the first aspect controls the towing vehicle in a state where the position relationship between the towing vehicle and the towed vehicle is restricted by the target bend angle, thereby enabling the towed vehicle to travel according to the target curvature.

[0009] In the first aspect, the towing vehicle control device can further include a wheel speed detection section that detects the speed of each wheel of the towing vehicle, and a bend angle detection section that detects the bend angle. In this case, the calculation section can generate the control signal including information on the requested speed of each wheel of the towing vehicle and information on the requested torque of each wheel of the towing vehicle, which are calculated based on each of the result of feedback control that eliminates the deviation between the target wheel speed of the towing vehicle and the wheel speed detected by the wheel speed detection section, and the result of feedback control that eliminates the deviation between the target bend angle and the bend angle detected by the bend angle detection section, which is calculated from the target vehicle body speed of the towing vehicle and the target curvature of the towing vehicle.

[0010] The towing vehicle control device according to the second aspect can generate the control signal including information on the requested speed of each wheel of the towing vehicle and information on the requested torque of each wheel of the towing vehicle by feedback control that eliminates the deviation between the actually detected observation value and the target value.

[0011] In the second aspect, the bend angle detection section can calculate the bend angle from the azimuth angle of the towing vehicle detected by an inertial measurement device mounted on the towing vehicle and the azimuth angle of the towed vehicle detected by an inertial measurement device mounted on the towed vehicle.

[0012] The towing vehicle control device according to the third aspect can detect the observation value of the bend angle of the towing vehicle and the towed vehicle using the inertial measurement devices mounted on many vehicles.

[0013] In the second aspect, the bend angle detection section can calculate the bend angle based on either the position of the towed vehicle in the image information acquired by an imaging device mounted on the towing vehicle or the position of the towing vehicle in the image information acquired by an imaging device mounted on the towed vehicle.

[0014] The towing vehicle control device according to the fourth aspect can detect the observation value of the bend angle of the towing vehicle and the towed vehicle using the imaging devices mounted on many vehicles.

[0015] According to the fifth aspect of the present disclosure, in any one of the first aspect to the fourth aspect, the operation section can calculate the target angle of bend in a case where the towing vehicle is traveling in a state of towing the towed vehicle.

[0016] The towing vehicle control device according to the fifth aspect controls the towing vehicle in a state where the position relationship between the towing vehicle and the towed vehicle is restricted by the target angle of bend, in a case where the towing vehicle is towing the towed vehicle to advance, and in a case where the towing vehicle is towing the towed vehicle to retreat, thereby enabling the towed vehicle to travel in accordance with the target curvature.

[0017] The sixth aspect of the present disclosure is a towing vehicle control method including processes of calculating a target vehicle body speed and a target curvature of a towing vehicle from a target vehicle body speed and a target curvature of a towed vehicle that is able to travel together with the towing vehicle in a state of being coupled to the towing vehicle by a coupling section that is a universal joint, calculating a target angle of bend that is a target value of an angle of bend formed by a traveling direction of the towing vehicle and a traveling direction of the towed vehicle, based on the target curvature of the towed vehicle, generating a control signal of the power of the towing vehicle based on the target vehicle body speed of the towing vehicle, the target curvature of the towing vehicle, and the target angle of bend, and controlling the power of the towing vehicle in accordance with the control signal.

[0018] The towing vehicle control method according to the sixth aspect enables the towed vehicle to travel in an appropriate trajectory by calculating a control condition of the towing vehicle in a case where the towed vehicle turns at a target curvature.

[0019] In some target curvatures, for example, there are cases where the towing vehicle and the towed vehicle interfere with each other, but the towing vehicle control method of the sixth aspect controls the towing vehicle in a state where the position relationship between the towing vehicle and the towed vehicle is restricted by the target angle of bend, thereby enabling the towed vehicle to travel in accordance with the target curvature.

[0020] The seventh aspect of the present disclosure is a computer-readable medium recording a tow vehicle control program that causes a computer to function as an arithmetic unit and a drive control unit, wherein the arithmetic unit calculates a target vehicle body speed and a target curvature of a tow vehicle from a target vehicle body speed and a target curvature of a towed vehicle that is able to travel together with the tow vehicle in a state of being coupled to the tow vehicle through a coupling portion that is a universal joint, and generates a control signal of the power of the tow vehicle based on a target bend angle that is a target value of a bend angle, the target vehicle body speed of the tow vehicle, and the target curvature of the tow vehicle, wherein the target bend angle is calculated based on the target curvature of the towed vehicle, and the bend angle is an angle formed by a traveling direction of the tow vehicle and a traveling direction of the towed vehicle, and the drive control unit controls the power of the tow vehicle in accordance with the control signal.

[0021] According to the seventh aspect, by calculating a control condition of the tow vehicle in a case where the towed vehicle turns at a target curvature, the towed vehicle is able to travel in an appropriate trajectory.

[0022] In some target curvatures, for example, sometimes the tow vehicle and the towed vehicle interfere with each other, but the seventh aspect controls the tow vehicle in a state where the positional relationship between the tow vehicle and the towed vehicle is restricted by the target bend angle, and thus the towed vehicle is able to travel in accordance with the target curvature.

[0023] According to the above aspects, the tow vehicle control device, the tow vehicle control method, and the computer-readable medium recording a tow vehicle control program of the present disclosure enable the towed vehicle to travel in an appropriate trajectory. BRIEF DESCRIPTION OF DRAWINGS

[0024] The exemplary embodiments are described in detail based on the following drawings, in which:

[0025] Figure 1 is a schematic diagram of a tow vehicle and a towed vehicle on which a tow vehicle control device of the first exemplary embodiment of the present disclosure is mounted.

[0026] Figure 2 is a block diagram showing one example of a configuration included in a tow vehicle of the tow vehicle control device of the first exemplary embodiment of the present disclosure.

[0027] Figure 3 is a block diagram showing one example of a configuration included in a towed vehicle of the tow vehicle control device of the first exemplary embodiment of the present disclosure.

[0028] Figure 4 is a block diagram showing one example of a specific configuration of an arithmetic device.

[0029] Figure 5 This is a flowchart illustrating an example of processing in the computing device of a traction vehicle according to a first exemplary embodiment of the present disclosure.

[0030] Figure 6 This is an illustrative diagram illustrating an example of the behavior of a towing vehicle and a towed vehicle during a turn.

[0031] Figure 7 This is an explanatory diagram showing the behavior of the tractor and the towed vehicle during the turning process when calculating the target angle.

[0032] Figure 8 This is an example of a motion diagram used to calculate the target wheel speed and target torque of the right wheel of a tractor vehicle.

[0033] Figure 9A This is a schematic diagram of a tractor vehicle towing a towed vehicle in the first exemplary embodiment.

[0034] Figure 9B This is a schematic diagram of a second exemplary embodiment where the tractor pushes the towed vehicle from behind.

[0035] Figure 10 This is a flowchart illustrating an example of processing in the computing device of a traction vehicle according to a second exemplary embodiment of the present disclosure. Detailed Implementation

[0036] [First Exemplary Implementation]

[0037] Hereinafter, this exemplary embodiment will be described in detail with reference to the accompanying drawings. Figure 1 As shown, the traction vehicle control device 10 of this exemplary embodiment includes a drive control device 16, which controls the drive unit 28 of the traction vehicle 100 by considering the driving trajectory of the towed vehicle 200 towed by the traction vehicle 100 in a state where it is connected to the traction vehicle 100 via the connecting part 150.

[0038] The towing vehicle 100 travels by rotating its right wheel 110R and left wheel 110L via a drive unit 28, which serves as a power source. The towed vehicle 200, while having a right wheel 210R and a left wheel 210L, does not have a power source and travels by being towed by the towing vehicle 100 via a connection 150. The drive unit 28, serving as the power source for the towing vehicle 100, can be an internal combustion engine, but it can also be an in-wheel motor located at each wheel to allow for flexible changes in the distribution of driving force by individually controlling each wheel.

[0039] The towing vehicle 100 can be either a manned vehicle driven by a driver or an autonomous vehicle that drives itself based on information about the surroundings of the towing vehicle 100 acquired by imaging devices 22 (22A, 22B, 22C, 22D), such as onboard cameras. The towed vehicle 200 is also equipped with imaging devices 62 (62A, 62B, 62C, 62D), which acquire extensive image information that aids in the autonomous driving of the towing vehicle 100.

[0040] Furthermore, the towing vehicle 100 turns by the difference in rotational speed between the left and right wheels. For example, if the rotational speed of the right wheel 110R is greater than the rotational speed of the left wheel 110L, the towing vehicle 100 makes a left turn. Conversely, if the rotational speed of the left wheel 110L is greater than the rotational speed of the right wheel 110R, the towing vehicle 100 makes a right turn.

[0041] The connecting part 150 is configured as a universal joint whose angle (bend) can freely change according to the movement of the towing vehicle 100 and the towed vehicle 200.

[0042] Figure 2 This is a block diagram illustrating an example of the configuration of the traction vehicle control device 10 included in the traction vehicle 100 according to this exemplary embodiment. Figure 2As shown, the configuration of the towing vehicle control device 10 included in the towing vehicle 100 is constituted by a storage device 18 that stores data required for the operation of the operation device 14 and an operation result obtained by the operation device 14, an image information processing section 20 that converts image information acquired by a camera 22 into a form that enables image analysis by the operation device 14, an input device 12 that inputs image information output by the image information processing section 20, a speed of each wheel of the towing vehicle 100 detected by a vehicle speed sensor 24, an angular velocity and an acceleration of a yaw angle of the towing vehicle 100 detected by an IMU (Inertial Measurement Unit) 26, and a current position of the towing vehicle 100 detected by a GNSS (Global Navigation Satellite System) device 30 that is a satellite positioning system based on information received from a satellite, the operation device 14 that generates a control signal for controlling a drive section 28 that is a power source of the towing vehicle 100, based on input data input from the input device 12 and data stored in the storage device 18, a V2X (Vehicle to X) communication section 36 that enables communication with a towed vehicle 200 and the like, and a drive control device 16 that controls the drive section 28 that is the power source of the towing vehicle 100 in accordance with the control signal generated by the operation in the operation device 14. With regard to the V2X communication section 36, wireless communication is assumed, but if the communication partner is limited to the towed vehicle 200, it can also be wired communication via a link section 150.

[0043] The IMU 26 is an inertial measurement device that can detect three-axis angular velocities (pitch angular velocity, roll angular velocity, yaw angular velocity) and three-axis accelerations (forward-backward acceleration, lateral acceleration, upward-downward acceleration) that represent the behavior of the vehicle while traveling.

[0044] Figure 3 is a block diagram showing one example of the configuration of the towing vehicle control device 10 of the present example embodiment included in the towed vehicle 200. As shown, the configuration of the towing vehicle control device 10 included in the towing vehicle 100 is constituted by a storage device 18 that stores data required for the operation of the operation device 14 and an operation result obtained by the operation device 14, an image information processing section 20 that converts image information acquired by a camera 22 into a form that enables image analysis by the operation device 14, an input device 12 that inputs image information output by the image information processing section 20, a speed of each wheel of the towing vehicle 100 detected by a vehicle speed sensor 24, an angular velocity and an acceleration of a yaw angle of the towing vehicle 100 detected by an IMU (Inertial Measurement Unit) 26, and a current position of the towing vehicle 100 detected by a GNSS (Global Navigation Satellite System) device 30 that is a satellite positioning system based on information received from a satellite, the operation device 14 that generates a control signal for controlling a drive section 28 that is a power source of the towing vehicle 100, based on input data input from the input device 12 and data stored in the storage device 18, a V2X (Vehicle to X) communication section 36 that enables communication with a towed vehicle 200 and the like, and a drive control device 16 that controls the drive section 28 that is the power source of the towing vehicle 100 in accordance with the control signal generated by the operation in the operation device 14. With regard to the V2X communication section 36, wireless communication is assumed, but if the communication partner is limited to the towed vehicle 200, it can also be wired communication via a link section 150. Figure 3As shown, the towing vehicle control device 10 includes the input device 52, the arithmetic device 54, the storage device 58, the imaging device 62, the image information processing section 60, the vehicle speed sensor 64, the IMU 66, the GNSS device 68, and the V2X communication section 70 in the towed vehicle 200 as well as in the towing vehicle 100, but does not have a power source, and thus does not have the drive control device 16 and the drive section 28 as a power source in the towing vehicle 100. As for the V2X communication section 70, wireless communication is assumed as with the V2X communication section 36 of the towing vehicle 100, but if the communication partner is limited to the towing vehicle 100, wired communication via the link section 150 is also possible.

[0045] The IMU 66 is an inertial measurement device that can detect three-axis angular velocity and three-axis acceleration indicating behavior of the vehicle while running, as with the IMU 26 of the towing vehicle 100.

[0046] The arithmetic device 54 performs calculation of a fold angle, which is an angle formed by a traveling direction of the towing vehicle 100 and a traveling direction of the towed vehicle 200, and the like, and is an angle of bending of the link section 150 according to running of the towing vehicle 100 and the towed vehicle 200 as described above. The fold angle can be calculated, for example, from image information acquired by the imaging device 62, or can be calculated based on information acquired by the IMU 66 and the GNSS device 68, respectively. The fold angle calculated by the arithmetic device 54 is output to the arithmetic device 14 of the towing vehicle 100 via the V2X communication section 70 and the V2X communication section 36 of the towing vehicle 100.

[0047] Figure 4 is a block diagram showing one example of a specific configuration of the arithmetic device 14. The arithmetic device 14 is a kind of computer, and includes a CPU (Central Processing Unit) 14B, a ROM (Read Only Memory) 14A, a RAM (Random Access Memory) 14C, and an input / output port 14D.

[0048] In the arithmetic device 14, the CPU 14B, the ROM 14A, the RAM 14C, and the input / output port 14D are connected to each other via various buses such as an address bus, a data bus, and a control bus. The input device 12, the storage device 18 as a hard disk (HDD), the drive control device 16, the V2X communication section 36, and the like as various input / output devices are connected to the input / output port 14D, respectively.

[0049] The storage device 18 has installed therein a tow vehicle control program that generates a control signal for controlling the drive section 28. In the present exemplary embodiment, the generation of the control signal for controlling the drive section 28 is performed by the CPU 14B executing the tow vehicle control program. Further, the CPU 14B outputs the control signal generated by the tow vehicle control program to the drive control device 16. Note that there are several methods of installing the tow vehicle control program of the present exemplary embodiment in the storage device 18, for example, the tow vehicle control program is stored in a CD-ROM (Compact Disc Read Only Memory), a DVD (Digital Versatile Disk), or the like together with a setup program in advance, the disk is set in a disk drive or the like as an input / output device, and the tow vehicle control program is installed in the storage device 18 by executing the setup program for the CPU 14B. Alternatively, the tow vehicle control program can be installed in the storage device 18 by communicating with another information processing apparatus connected to the computing device 14 via a public telephone line or a network.

[0050] Next, various functions realized by the CPU 14B of the computing device 14 executing the tow vehicle control program will be described. The tow vehicle control program functions as a towed vehicle target speed / curvature computation function that computes a target speed and a target curvature of the towed vehicle 200, a tow vehicle target speed / curvature computation function that computes a target speed and a target curvature of the tow vehicle 100, a travel direction determination function that determines a travel direction of the tow vehicle 100, a target cornering angle computation function that computes a target cornering angle, and a tow vehicle individual wheel target wheel speed computation function that computes target wheel speeds of the individual wheels of the tow vehicle 100. The CPU 14B functions as the towed vehicle target speed / curvature computation section 40, the tow vehicle target speed / curvature computation section 42, the travel direction determination section 44, the target cornering angle computation section 46, and the tow vehicle individual wheel target wheel speed computation section 48 by executing the tow vehicle control program.

[0051] Figure 5 Fig. 17 is a flowchart showing one example of the processing in the computing device 14 of the tow vehicle 100 of the tow vehicle control device 10 of the present exemplary embodiment.

[0052] In step S100, the target speed and the target curvature of the towed vehicle 200 are calculated. In the case where the towing vehicle 100 is a manned vehicle, as an example, the speed of the towing vehicle 100 is set as the target speed of the towed vehicle 200, and the target curvature is calculated based on the operation amount of the driver of the towing vehicle 100. For example, the yaw rate Y detected by the IMU 26 of the towing vehicle 100 is divided by the speed V of the towing vehicle 100 as in the following equation T , and the quotient is set as the target curvature K of the towed vehicle 200 t .

[0053] K t = Y / V T

[0054] Since the yaw rate of the towing vehicle 100 is also the difference between the wheel speed V Tr of the right wheel 110R of the towing vehicle 100 and the wheel speed V Tl of the left wheel 110L divided by the distance T (wheel base) between the right wheel 110R and the left wheel 110L, the difference between the wheel speed V Tr of the right wheel 110R of the towing vehicle 100 and the wheel speed V Tl of the left wheel 110L is also divided by the product of the wheel base T and the speed V T of the towing vehicle 100 as in the following equation, and the quotient is set as the target curvature K of the towed vehicle 200 t .

[0055] K t = (V Tr - V Tl ) / T · V T

[0056] Alternatively, the target speed and the target curvature K of the towed vehicle 200 can be arbitrarily set t .

[0057] In step S102, the target speed and the target curvature of the towing vehicle 100 are calculated from the target speed and the target curvature of the towed vehicle 200.

[0058] Figure 6 is an explanatory diagram showing an example of the behavior of the towing vehicle 100 and the towed vehicle 200 in a turn. In Figure 6 , the target speed V tu of the towed vehicle 200, the target curvature K t of the towed vehicle 200, the target speed V Tx of the towing vehicle 100, and the target curvature KT , the angle of fold φ, the distance 1 from the axle position of the towing vehicle 100 to the joint 150 wb , the distance 13 from the joint 150 to the axle position of the towed vehicle 200, the distance, i.e., the turning radius R, from the turning center 120 of the towing vehicle to the middle point of the right wheel 110R and the left wheel 110L of the towing vehicle 100 T , and the distance, i.e., the turning radius R, from the turning center 220 of the towed vehicle to the middle point of the right wheel 210R and the left wheel 210L of the towed vehicle 200 t .

[0059] Based on the state shown in FIG. 6, the following equations (1) and (2) are defined. Figure 6

[0060]

[0061]

[0062] From the above equations (1) and (2), the equation (3) for calculating the target speed V Tx of the towing vehicle 100 and the equation (4) for calculating the target curvature κ T of the towing vehicle 100 are derived. In step S102, using the following equations (3) and (4), the target speed V tu and the target curvature κ t of the towing vehicle 100 are calculated from the target speed V Tx and the target curvature κ T of the towed vehicle 200.

[0063]

[0064]

[0065] In step S104, it is determined whether the towing vehicle 100 is advancing. As one example, the determination of whether the towing vehicle 100 is advancing is made based on the direction of acceleration detected by the IMU 26 possessed by the towing vehicle 100. This is because, in the case where the towing vehicle 100 is towing the towed vehicle 200, the angle of fold φ becomes a problem only when advancing.

[0066] In the case where it is determined in step S104 that the towing vehicle 100 is advancing, the process is moved to step S106, and in the case where it is determined that the towing vehicle 100 is not advancing, the process is moved to step S108.

[0067] In step S106, the target angle of fold φ ref . Figure 7 is calculated. The target angle of fold φ ref ​a diagram of the behavior of the towing vehicle 100 and the towed vehicle 200 in a turn at the time of calculation. In Figure 7 the turning center of the towing vehicle 100 and the turning center of the towed vehicle 200 are made consistent as a towed vehicle turning center and a towing vehicle turning center (hereinafter, abbreviated as "turning center") 130.

[0068] As shown in Figure 7 , in the case of the towing vehicle 100 in a turning state, the intermediate points of the right wheel 110R and the left wheel 110L move in the x-axis direction at a target speed V Tx , and move in the y-axis direction at a lateral speed V c , and a yaw angular velocity ω Tz is generated at the intermediate points of the right wheel 110R and the left wheel 110L.

[0069] Further, in the case of the towed vehicle 200 in a turning state, the intermediate points of the right wheel 210R and the left wheel 210L move in the u-axis direction at a target speed V tu , and move in the v-axis direction at a lateral speed V d , and a yaw angular velocity ω tw is generated at the intermediate points of the right wheel 210R and the left wheel 210L. Also, the coupling portion 150 moves in the direction of the speed vector 160.

[0070] In this case, the target fold angle φ ref is represented by the following equation (5).

[0071]

[0072] As shown in Figure 7 , the tangent of α1 is R ref / l3(R ref = 1 / κ ref ), and therefore α1 is represented by the following equation (6).

[0073]

[0074] Further, as shown in Figure 7 , the tangent of α2 is R T / l wb , and therefore α2 is represented by the following equation (7).

[0075]

[0076] The square of the distance of the coupling portion 150 from the turning center 130, that is, L 2 , is represented as follows.

[0077]

[0078] As a result, R in the above equation (7) is calculated as T is represented by the following equation (8). R T Also, as shown in the following equation (9), the target curvature κ Figure 6 of the towing vehicle 100 can be calculated in the form of the reciprocal. T

[0079]

[0080] In step S106, the target fold angle φ ref is calculated using the above equations (5) to (8).

[0081] In step S108, the target wheel speed of each wheel of the towing vehicle 100 is calculated. Hereinafter, as an example, the target wheel speed of the right wheel 110R is calculated, but the target wheel speed of the left wheel 110L can be calculated in the same manner.

[0082] Figure 8 is an example of an activity chart when the target wheel speed and the target torque of the right wheel of the towing vehicle 100 are calculated. In step S1, the target vehicle body speed VTx_ref (= V Tx ) of the towing vehicle 100 is input, in step S2, the target curvature curv_ref (= κ T ) of the towing vehicle 100 is input, in step S3, the wheel speed of the right wheel 110R of the towing vehicle 100 as an observed value detected by the vehicle speed sensor 24 is input, in step S4, the target fold angle φ ref is input, and in step S5, the fold angle φ as an observed value is input. As the fold angle φ as an observed value, as an example, the fold angle φ is calculated by comparing the azimuth angle of the towing vehicle 100, which is obtained by time-integrating the yaw rate detected by the IMU 26 with reference to the position of the towing vehicle 100 in the earth coordinates detected by the GNSS device 30 of the towing vehicle 100, with the azimuth angle of the towed vehicle 200, which is obtained by time-integrating the yaw rate detected by the IMU 66 with reference to the position of the towed vehicle 200 in the earth coordinates detected by the GNSS device 68 of the towed vehicle 200.

[0083] ​The fold angle φ as an observation value can also be calculated from the image information acquired by the imaging device 22 of the towing vehicle 100 or the imaging device 62 of the towed vehicle 200. Specifically, the fold angle φ as an observation value is calculated on the basis of the position of the towed vehicle 200 in the image information acquired by the imaging device 22B of the towing vehicle 100. Alternatively, the fold angle φ as an observation value can also be calculated on the basis of the position of the towing vehicle 100 in the image information acquired by the imaging device 62A of the towed vehicle 200.

[0084] In block B1, the target wheel speed of the towing vehicle 100 is calculated on the basis of the target vehicle body speed VTx_ref and the target curvature curv_ref. As described above, the yaw rate of the towing vehicle 100 is the difference between the wheel speed V Tr of the right wheel 110R of the towing vehicle 100 and the wheel speed V Tl of the left wheel 110L divided by the distance between the right wheel 110R and the left wheel 110L, i.e., the track T. The target curvature curv_ref is the quotient of the yaw rate of the towing vehicle 100 divided by the target vehicle body speed VTx_ref of the towing vehicle 100, and thus the relationship of the following equation is confirmed.

[0085] curv_ref = (V Tr - V Tl ) / T • VTx_ref

[0086] As one example, in block B1, for example, in the case where the towing vehicle 100 makes a left turn, the target wheel speeds of the right wheel 110R and the left wheel 110L are calculated on the premise that V Tr > VTx_ref > V Tl in the above equation holds.

[0087] The target wheel speed calculated in block B1 is eliminated of the deviation from the wheel speed of the right wheel 110R of the towing vehicle 100 as an observation value detected by the vehicle speed sensor 24 in the subsequent block B2 by PI control (Proportional-Integral Controller) as feedback control. In block B2, P control that eliminates the deviation in a linear function and I control that eliminates the deviation in proportion to the time integral of the deviation are executed.

[0088] The target fold angle φ ref in block B3 is eliminated of the deviation from the fold angle φ as an observation value input in step S5 by P control as feedback control.

[0089] Then, the right wheel target torque is calculated based on the output result of the module B2 and the output result of the module B3. As an example, an algorithm for calculating the right wheel target torque based on the value of the right wheel speed as the output result of the module B2 and the value of the folding angle φ as the output result of the module B3 is constructed by machine learning or the like.

[0090] After the target wheel speeds (and target torques) of the wheels of the towing vehicle 100 are calculated in step S108, the process is ended.

[0091] The operation device 14 outputs a control signal including the calculated target wheel speeds (and target torques) of the wheels of the towing vehicle 100 to the drive control device 16, and the drive control device 16 controls the drive section 28 in accordance with the input control signal.

[0092] As described above, according to the present exemplary embodiment, by calculating the control condition of the towing vehicle 100 in the case where the towed vehicle 200 turns with an arbitrary curvature, the towed vehicle can be caused to travel with an appropriate trajectory.

[0093] In the present exemplary embodiment, when the target wheel speeds of the wheels of the towing vehicle 100 as the control condition of the towing vehicle 100 are calculated, the value of the target curvature κ T of the towing vehicle 100 is required, but as shown in Figure 6 , the target curvature κ T of the towing vehicle 100 can be calculated using geometry.

[0094] However, under some travel conditions, it is difficult to cause the towing vehicle 100 to travel with the target curvature κ T calculated using geometry. For example, in the case where the towing vehicle 100 interferes with the towed vehicle 200 when the towing vehicle 100 is caused to travel with the target curvature κ T , the positional relationship of the towing vehicle 100 and the towed vehicle 200 does not hold, and the towing vehicle 100 cannot be caused to travel with the calculated target curvature κ T .

[0095] In the present exemplary embodiment, by imposing a constraint on the positional relationship of the towing vehicle 100 and the towed vehicle 200, the target curvature κ t of the towed vehicle 200 can be arbitrarily set in a simulation manner. The constraint on the positional relationship in the present exemplary embodiment is specifically a folding angle φ, which is an angle formed by the towing vehicle 100 and the towed vehicle 200. In the present exemplary embodiment, a target folding angle φ ref for achieving a certain target curvature is approximately calculated and considered as a constraint on the positional relationship of the towing vehicle 100 and the towed vehicle 200.

[0096] In geometry, the folding angle φ is not determined uniquely by the arbitrary target curvature κ t The target folding angle φ is determined uniquely, but in the present exemplary embodiment, it is set arbitrarily by reflecting the target curvature κ ref Approximating the target value and reflecting it to the control of the towing vehicle 100, the target curvature κ t .

[0097] In general, the towed vehicle 200 carries passengers or cargo, and the towed vehicle 200 becomes a primary existence when considering a travel trajectory. On the other hand, the towing vehicle 100 that is towing the towed vehicle 200 is a secondary existence with respect to the towed vehicle 200. Further, in a case where the towed vehicle 200 is very large like a trailer, control that matches the size of the towed vehicle 200 is required. In the present exemplary embodiment, as described above, the target curvature κ t of the towed vehicle 200 can be set arbitrarily, and thus control of the towing vehicle 100 that corresponds to the movement of the towed vehicle 200 can be performed as long as how the towed vehicle 200 moves is considered first.

[0098] [Second Exemplary Embodiment]

[0099] Next, a second exemplary embodiment of the present disclosure will be described. Figure 9A is a schematic diagram in a case where the towing vehicle 100 in the first exemplary embodiment is towing the towed vehicle 200, Figure 9B is a schematic diagram in a case where the towing vehicle 100 in the present exemplary embodiment is pushing the towed vehicle 200 from behind. The present exemplary embodiment differs from the first exemplary embodiment in that the towing vehicle 100 is pushing the towed vehicle 200 from behind or towing the towed vehicle 200, and thus the configurations of the towing vehicle 100 and the towed vehicle 200 are the same as those in the first exemplary embodiment. Therefore, for the configurations that are the same as those in the first exemplary embodiment, the same reference numerals are attached and detailed description will be omitted.

[0100] Figure 10 is a flowchart showing one example of processing in the operation device 14 of the towing vehicle 100 of the towing vehicle control device 10 of the present exemplary embodiment.

[0101] In step S200, the target speed and the target curvature of the towed vehicle 200 are calculated similarly to step S100 of the first exemplary embodiment. Figure 5 of the first exemplary embodiment. The target speed and the target curvature κ t of the towed vehicle 200 can also be set arbitrarily.

[0102] In step S202, compared with the first exemplary embodiment Figure 5 Similarly, step S102 calculates the target speed and target curvature of the towing vehicle 100 based on the target speed and target curvature of the towing vehicle 200.

[0103] In step S204, compared with the first exemplary embodiment Figure 5 Step S104 similarly determines whether the towing vehicle 100 is moving forward. As an example, the determination of whether it is moving forward is based on the direction of acceleration detected by the IMU26 of the towing vehicle 100. When the towing vehicle 100 pushes the towed vehicle 200 from behind, the angle φ only becomes problematic during reversal. This is because, during reversal in this exemplary embodiment, the state of the towing vehicle 100 towing the towed vehicle 200 is the same as during forward movement in the first exemplary embodiment.

[0104] If it is determined in step S204 that the tractor vehicle 100 is moving forward, the process moves to step S208; if it is determined that the tractor vehicle 100 is not moving forward, the process moves to step S206.

[0105] In step S206, compared with the first exemplary embodiment Figure 5 Similarly, in step S106, the target bending angle φ is calculated. ref .

[0106] In step S208, compared with the first exemplary embodiment Figure 5 Similarly, step S108 calculates the target wheel speeds of each wheel of the traction vehicle 100.

[0107] After calculating the target wheel speed (and target torque) of each wheel of the traction vehicle 100 in step S208, the process ends.

[0108] The computing device 14 outputs a control signal containing the calculated target wheel speed (and target torque) of each wheel of the traction vehicle 100 to the drive control device 16, and the drive control device 16 controls the drive unit 28 according to the input control signal.

[0109] As explained above, according to this exemplary embodiment, when the tractor 100 and the towed vehicle 200 are reversing, by reflecting the target bending angle in the control of the tractor 100, the target curvature κ of the towed vehicle 200 can be arbitrarily set. t Furthermore, by calculating the tractor 200 at an arbitrary target curvature κ... t The control conditions of the tractor 100 when turning enable the towed vehicle to travel along an appropriate trajectory.

[0110] Note that the processing performed by the CPU that reads and executes the software (program) in each of the above-described example embodiments can also be performed by various processors other than the CPU. As the processor in this case, a PLD (Programmable Logic Device) such as an FPGA (Field-Programmable Gate Array) that can change the circuit configuration after manufacture, and an ASIC (Application Specific Integrated Circuit) and the like that are special-purpose electric circuits as processors having a circuit configuration designed specifically to perform a certain processing, and the like can be exemplified. Furthermore, the processing can be performed by one of these various processors, or can be performed by a combination of two or more processors of the same kind or different kinds (for example, a plurality of FPGAs, a combination of a CPU and an FPGA, and the like). Furthermore, more specifically, the hardware structure of these various processors is an electric circuit in which circuit elements such as semiconductor elements are combined.

[0111] Furthermore, in each of the above-described example embodiments, a scheme in which a program is stored (installed) in advance in a disk drive or the like is described, but is not limited thereto. The program can also be provided in a form in which it is stored in a non-transitory storage medium such as a CD-ROM (Compact Disk Read Only Memory), a DVD-ROM (Digital Versatile Disk Read Only Memory), and a USB (Universal Serial Bus) memory. Furthermore, the program can also be in a form in which it is downloaded from an external device via a network.

[0112] Note that the "arithmetic unit" in the claim corresponds to the "arithmetic device 14" in the detailed description of the invention of the specification, the "drive control unit" in the claim corresponds to the "drive control device 16" in the detailed description of the invention of the specification, the "wheel speed detection unit" recited in the claim corresponds to the "vehicle speed sensor 24" in the detailed description of the invention of the specification, and the "corner detection unit" in the claim corresponds to the "IMU 26", the "imaging device 22", and the "arithmetic device 14" in the detailed description of the invention of the specification.

[0113] (Additional item 1)

[0114] A towing vehicle control device includes a memory and at least one processor connected to the memory, the processor configured to calculate a target vehicle body speed and a target curvature of a towing vehicle from a target vehicle body speed and a target curvature of a towed vehicle that can travel together with the towing vehicle in a state of being coupled to the towing vehicle by a coupling portion that is a universal joint, calculate a target turning angle that is a target value of a turning angle formed by a traveling direction of the towing vehicle and a traveling direction of the towed vehicle based on the target curvature of the towed vehicle, generate a control signal of the power of the towing vehicle based on the target vehicle body speed of the towing vehicle, the target curvature of the towing vehicle, and the target turning angle, and control the power of the towing vehicle in accordance with the control signal.

Claims

1. A traction vehicle control device, comprising: The arithmetic unit calculates the target vehicle speed and target curvature of the towing vehicle based on the target vehicle speed and target curvature of the towing vehicle, which is connected to the towing vehicle via a universal joint and travels together with the towing vehicle. Based on the target curvature of the towing vehicle, it calculates a target angle as a target value of the angle. Based on the target vehicle speed, the target curvature of the towing vehicle, and the target angle, it generates a control signal for the power of the towing vehicle. The angle is the angle formed by the travel direction of the towing vehicle and the travel direction of the towing vehicle. The drive control unit controls the power of the traction vehicle according to the control signal; A wheel speed detection unit detects the speed of each wheel of the tractor vehicle; and The angle detection unit detects the angle. The arithmetic unit generates the control signal containing information on the requested speed of each wheel of the traction vehicle and information on the requested torque of each wheel of the traction vehicle. The information on the requested speed of each wheel of the traction vehicle and the information on the requested torque of each wheel of the traction vehicle are calculated based on the results of feedback control that eliminates the deviation between the target wheel speed of the traction vehicle and the detected wheel speed, and the results of feedback control that eliminates the deviation between the target angle and the detected angle. The target wheel speed of the traction vehicle is calculated based on the target body speed of the traction vehicle and the target curvature of the traction vehicle.

2. The traction vehicle control device according to claim 1, wherein, The angle detection unit calculates the angle based on the azimuth angle of the tractor vehicle detected by the inertial measurement device mounted on the tractor vehicle and the azimuth angle of the towed vehicle detected by the inertial measurement device mounted on the towed vehicle.

3. The traction vehicle control device according to claim 1, wherein, The angle detection unit calculates the angle based on either the position of the towed vehicle in the image information obtained by the camera mounted on the towing vehicle or the position of the towing vehicle in the image information obtained by the camera mounted on the towing vehicle.

4. The traction vehicle control device according to any one of claims 1 to 3, wherein, The calculation unit calculates the target angle when the tractor vehicle is traveling in a state of towing the towed vehicle.

5. A method for controlling a traction vehicle, comprising: The target vehicle speed and target curvature of the towing vehicle are calculated based on the target vehicle speed and target curvature of the towing vehicle, which is connected to the towing vehicle with power through the connection part as a universal joint. The target angle is calculated as the target value of the angle of curvature of the towed vehicle, wherein the angle of curvature is the angle formed by the travel direction of the towing vehicle and the travel direction of the towed vehicle. The speed of each wheel of the traction vehicle is detected, and the bending angle is detected; A control signal for the power of the traction vehicle is generated based on the target vehicle speed, the target curvature of the traction vehicle, and the target angle of curvature. The control signal includes information on the requested speed and requested torque of each wheel of the traction vehicle. This requested speed and requested torque information are calculated based on the results of feedback control that eliminates the deviation between the target wheel speed and the detected wheel speed, and the results of feedback control that eliminates the deviation between the target angle and the detected angle of curvature. The target wheel speed of the traction vehicle is calculated based on the target vehicle speed and the target curvature of the traction vehicle. The power of the traction vehicle is controlled according to the control signal.

6. A computer-readable medium recording a traction vehicle control program, wherein the traction vehicle control program enables a computer to function as a wheel speed detection unit, a turning angle detection unit, a calculation unit, and a drive control unit, wherein... The wheel speed detection unit detects the speed of each wheel of the traction vehicle. The angle detection unit detects the angle, wherein the angle is the angle formed by the travel direction of the tractor vehicle and the travel direction of the towed vehicle. The calculation unit calculates the target body speed and target curvature of the traction vehicle based on the target body speed and target curvature of the towed vehicle, which is connected to the powered traction vehicle via a connector that functions as a universal joint. Based on the target curvature of the towed vehicle, it calculates a target angle as the target value of the angle. Based on the target body speed, target curvature, and target angle of the traction vehicle, it generates a control signal for the power of the traction vehicle. This control signal includes information on the requested speed and requested torque of each wheel of the traction vehicle. The requested speed and requested torque information of each wheel are calculated based on the results of feedback control that eliminates the deviation between the target wheel speed and the detected wheel speed, and the results of feedback control that eliminates the deviation between the target angle and the detected angle. The target wheel speed of the traction vehicle is calculated based on the target body speed and target curvature of the traction vehicle. The drive control unit controls the power of the traction vehicle according to the control signal.

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