Power-assisted steering control method and control system for storage vehicle

Abstract

The power-assisted steering control method for the storage vehicle comprises the following steps that S1, the angle theta 1 of a driving wheel is obtained, whether the driving wheel enters a steering tail end protection area or not is judged, and if not, S2 is executed; if so, executing S3; s2, the output assisting power of the power-assisted steering system is the assisting power Fmax under the maximum efficiency, and the step S1 is executed; s3, the rotating direction of the steering wheel and the change trend of the angle theta 1 of the driving wheel are obtained, and if the absolute value of the angle theta 1 of the driving wheel is increased, S4 is executed; if the absolute value of the driving wheel angle theta1 is reduced, executing S5; s4, gradually reducing the power output by the power-assisted steering system until the power Fmin at the minimum efficiency; and S5, the power output by the power-assisted steering system is gradually increased till the power Fmax under the maximum efficiency, the position and the steering trend of the driving wheel are obtained, the power-assisted mechanism system protects the steering tail end of the driving wheel, and the situation that the driving wheel rotates to the tail end to impact a limiting device is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of steering, and in particular to a power steering control method and a control system for a storage vehicle. Background Art

[0002] At present, the power steering of warehouse vehicles is equipped with a steering wheel limit mechanism. At the steering end, the driving wheel turns close to the limit device. If the hand force acting on the steering wheel is very large, plus the power assistance of the power steering system, the steering wheel will hit the limit mechanism at the end, causing damage to mechanical and electronic components and the entire vehicle cannot operate normally. When the hand force provided by the operator and the power assistance provided by the power steering system at the steering end are both very large, turning the steering wheel in the opposite direction needs to overcome a lot of resistance. The operator will obviously feel the heavy feel, and the entire vehicle will not be smooth to operate. Summary of the Invention

[0003] The object of the present invention is to provide a power steering control method and control system for a storage vehicle to solve the problems raised in the above background technology.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A power steering control method for a storage vehicle comprises the following steps:

[0006] S1. Obtain the driving wheel angle θ1 and determine whether the driving wheel enters the steering end protection zone. If not, execute S2; if yes, execute S3.

[0007] S2: The power steering system outputs the power assist at the maximum efficiency Fmax, and executes S1;

[0008] S3, obtaining the steering wheel rotation direction and the change trend of the driving wheel angle θ1. If the absolute value of the driving wheel angle θ1 is increasing, execute S4; if the absolute value of the driving wheel angle θ1 is decreasing, execute S5;

[0009] S4, gradually reduce the power output of the power steering system until it reaches the power output Fmin at the minimum efficiency, and execute S1;

[0010] S5. Gradually increase the power steering system output until the power steering reaches Fmax at maximum efficiency, and execute S1.

[0011] As a further solution of the present invention: in S1, the zero position state of the driving wheel is first determined, and the zero position state of the driving wheel refers to the position where the driving wheel position and the vehicle axis coincide with each other.

[0012] As a further solution of the present invention: the driving wheel position is in a zero position state, and a zero position information instruction is sent through the vehicle instrument. After receiving the instruction, the power assist controller and the vehicle controller memorize the driving wheel position.

[0013] As a further solution of the present invention: the steering angle θ1 of the driving wheel in S1 is in the range of -90°-+90°, and the instantaneous clockwise rotation of the steering wheel is positive and counterclockwise rotation is negative. The angle range of the end protection zone is 0-5°, and the steering angle θ1 of the driving wheel in the clockwise end protection zone is in the range of +85°-+90°; the steering angle θ1 of the driving wheel in the counterclockwise end protection zone is in the range of -85°--90°.

[0014] As a further solution of the present invention: in S4, the angle of the driving wheel is located in the clockwise end protection zone or the counterclockwise end protection zone, and the steering increases, the driving wheel gradually approaches the steering end, and the corresponding output power F of the power assist system is linearly weakened until the power assist Fmin is reached at the minimum efficiency.

[0015] As a further solution of the present invention: in S5, the angle of the driving wheel is located in the clockwise end protection zone or the counterclockwise end protection zone, and the steering gradually decreases, the driving wheel gradually moves away from the steering end, and the power assist system will linearly increase the power assist F until it reaches the power assist Fmax at maximum efficiency.

[0016] A power steering control system for a storage vehicle comprises a vehicle frame and a transmission device arranged on the vehicle frame, wherein the transmission device is connected to a driving wheel set in a power manner, and the driving wheel set is connected to a steering device and a steering assist device in a power manner;

[0017] The steering device includes a steering wheel and a torsion bar dynamically connected to the steering wheel, wherein the torsion bar is dynamically connected to the driving wheel set to drive the driving wheel set to steer;

[0018] The power steering device is dynamically connected to the torsion bar.

[0019] As a further solution of the present invention: a torque sensor and an angle sensor are provided on the torsion bar, and the torque sensor and the angle sensor are connected to a power assist system controller through line signals, and the power assist system controller is connected to the power assist device.

[0020] As a further solution of the present invention: the power-assisting device includes a power-assisting motor, and the power-assisting motor is dynamically connected to the torsion bar through a reduction structure.

[0021] As a further solution of the present invention: the power assist system controller signal is connected to the vehicle instrument, the vehicle instrument signal is connected to the vehicle controller, and the power assist system controller, vehicle instrument and vehicle controller are connected to the vehicle power supply.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: the present application adopts an angle sensor to detect the steering angle and rotation direction of the steering wheel in real time, converts it into the position of the driving wheel, and the power assist mechanism system combines the terminal protection lineup curve and the power assist participation lineup curve to provide corresponding power assist in real time, thereby protecting the steering end of the driving wheel and reducing the impact of the driving wheel on the end limit device; when the driving wheel rotates from the end, the power assist mechanism system combines the terminal protection lineup curve and the power assist participation lineup curve to continuously increase the power assist and reduce the physical feeling of heavy steering wheel operation, making the steering wheel operation smoother and more labor-saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the power assist system of this embodiment;

[0024] Figure 2 This is the end protection lineup curve of this embodiment;

[0025] Figure 3 To assist in participating in the lineup curve for this embodiment;

[0026] In the figure: 1-frame, 2-transmission device, 3-steering wheel, 4-torsion bar, 5-torque sensor, 6-angle sensor, 7-power system controller, 8-power motor, 9-reduction mechanism, 10-vehicle instrument, 11-vehicle controller, 12-drive wheel set, 13-vehicle power supply. DETAILED DESCRIPTION

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0028] See also Figure 1-3 In an embodiment of the present invention, a power steering control system for a storage vehicle includes a frame 1 and a transmission device 2, a steering wheel 3, a torsion bar 4, a power controller 7, a power motor 8, a vehicle instrument 10, a vehicle controller 11, and a vehicle power supply 13 arranged on the frame 1; the steering wheel 3 is connected to the input shaft of the torsion bar 4; a torque sensor 5 and an angle sensor 6 are provided on the torsion bar; the output shaft of the torsion bar 4 is connected to the transmission device 2; the power motor 8 is provided with a speed reduction mechanism 9; the speed reduction mechanism 9 is connected to the output shaft of the torsion bar 4; the vehicle controller 11, the power controller 7, the vehicle instrument 10, and the vehicle power supply 13 are electrically connected; and the vehicle power supply 13 supplies power to the vehicle.

[0029] See also Figure 2 , Figure 3, the driving wheel angle is less than or equal to 85° (absolute value), the driving wheel position is not in the end protection zone, the power controller controls the motor to provide power Fmax (absolute value), the steering wheel rotates clockwise, Fmax takes a positive value; the steering wheel rotates counterclockwise, Fmax takes a negative value;

[0030] The driving wheel angle is greater than 85° (absolute value), and the driving wheel position is in the end protection zone. When the steering wheel rotation direction is consistent with the driving wheel running direction, the power assist controller controls the motor in combination with the end protection lineup curve and the power assist participation lineup curve, linearly reducing the power assist provided at maximum efficiency (Fmax (absolute value) to the power assist provided at minimum efficiency (Fmin (absolute value)).

[0031] The driving wheel angle is greater than 85° (absolute value), and the driving wheel position is in the end protection zone. When the steering wheel rotation direction is inconsistent with the driving wheel running direction, the power assist controller controls the motor based on the end protection lineup curve and the power assist participation lineup curve, linearly increasing the power assist provided at the minimum efficiency Fmin (absolute value) to the maximum efficiency Fmax (absolute value).

[0032] A power steering control method for a warehouse vehicle first determines the zero position state of the driving wheel. The zero position state of the driving wheel refers to the position where the driving wheel position and the vehicle axis coincide with each other. The driving wheel position is in the zero position state. A zero position information instruction is sent through the vehicle instrument. After receiving the instruction, the power steering controller and the vehicle controller memorize the driving wheel position. After determining the zero position of the driving wheel, the above operation does not need to be repeated subsequently.

[0033] The control method includes the following steps:

[0034] S1. Obtain the driving wheel angle θ1 and determine whether the driving wheel enters the steering end protection zone. If not, execute S2; if so, execute S3. In this embodiment, the range of the driving wheel steering angle θ1 is -90°-+90°, and the steering wheel instantaneously rotates clockwise as positive and counterclockwise as negative. The angle range of the end protection zone is 0-5°. The steering angle θ1 of the driving wheel in the clockwise end protection zone is +85°-+90°; the steering angle θ1 of the driving wheel in the counterclockwise end protection zone is -85°--90°.

[0035] S2: When the hand force F0 is applied to the steering wheel and the driving wheel is not in the end protection zone, the power assist controller controls the motor to provide the maximum efficiency power assist Fmax (absolute value) and executes S1.

[0036] S3, obtaining the steering wheel rotation direction and the change trend of the driving wheel angle θ1. If the absolute value of the driving wheel angle θ1 is increasing, execute S4; if the absolute value of the driving wheel angle θ1 is decreasing, execute S5;

[0037] S4: When the hand force F0 is applied to the steering wheel, the angle of the driving wheel is within the clockwise end protection zone or the counterclockwise end protection zone, and the steering increases, the driving wheel gradually approaches the steering end according to the combined end face protection curve and the power assistance participation curve. The corresponding output power F of the power assistance system is linearly reduced until it reaches the power assistance Fmin at the minimum efficiency, reducing the terminal steering speed, and executing S1.

[0038] S5. When the hand force F0 acts on the steering wheel, the angle of the driving wheel is within the clockwise end protection zone or the counterclockwise end protection zone, and the steering gradually decreases. According to the combined end face-lift protection curve and the power assistance participation curve, the driving wheel gradually moves away from the steering end. The power assistance system will linearly increase the power assistance F until it reaches the power assistance Fmax at maximum efficiency, increase the power assistance, reduce the heavy feeling of turning the steering wheel, and execute S1.

[0039] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0040] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A power steering control method for a storage vehicle, characterized in that: The following steps are involved: S1. Obtain the driving wheel angle θ1 and determine whether the driving wheel enters the steering end protection zone. If not, execute S2; if yes, execute S3. S2: The power steering system outputs the power assist at the maximum efficiency Fmax, and executes S1; S3, obtaining the steering wheel rotation direction and the change trend of the driving wheel angle θ1. If the absolute value of the driving wheel angle θ1 is increasing, executing S4; if the absolute value of the driving wheel angle θ1 is decreasing, executing S5; S4, gradually reduce the power output of the power steering system until it reaches the power output Fmin at the minimum efficiency, and execute S1; S5. Gradually increase the power steering system output until the power steering reaches Fmax at maximum efficiency, and execute S1.

2. The power steering control method for a storage vehicle according to claim 1, characterized in that: In S1, the zero position state of the driving wheel is first determined. The zero position state of the driving wheel refers to the position where the driving wheel position and the vehicle axis coincide with each other.

3. The power steering control method for a storage vehicle according to claim 2, characterized in that: The driving wheel position is in a zero position state, and a zero position information instruction is sent through the vehicle instrument. After receiving the instruction, the power assist controller and the vehicle controller memorize the driving wheel position.

4. The power steering control method for a storage vehicle according to claim 1, characterized in that: The steering angle θ1 of the driving wheel in S1 ranges from -90° to +90°, and the instantaneous clockwise rotation of the steering wheel is positive and counterclockwise rotation is negative. The angle range of the end protection zone is 0-5°, and the steering angle θ1 of the driving wheel in the clockwise end protection zone ranges from +85° to +90°; the steering angle θ1 of the driving wheel in the counterclockwise end protection zone ranges from -85° to -90°.

5. The power steering control method for a storage vehicle according to claim 1, characterized in that: In S4, the angle of the driving wheel is within the clockwise end protection zone or the counterclockwise end protection zone, and the steering increases, the driving wheel gradually approaches the steering end, and the corresponding output power F of the power assist system is linearly reduced until the power assist Fmin is achieved at the minimum efficiency.

6. The power steering control method for a storage vehicle according to claim 1, characterized in that: In S5, the angle of the driving wheel is within the clockwise end protection zone or the counterclockwise end protection zone, and the steering gradually decreases, the driving wheel gradually moves away from the steering end, and the power assist system linearly increases the power assist F until the power assist Fmax is achieved at maximum efficiency.

7. A power steering control system for a storage vehicle using the power steering control method according to any one of claims 1 to 6, characterized in that: The vehicle comprises a frame (1) and a transmission device (2) arranged on the frame (1), wherein the transmission device (2) is dynamically connected to a driving wheel set (12), and the driving wheel set (12) is dynamically connected to a steering device and a steering assist device; The steering device comprises a steering wheel and a torsion bar (4) dynamically connected to the steering wheel, wherein the torsion bar (4) is dynamically connected to the driving wheel set (12) for driving the driving wheel set (12) to steer; The steering assist device is dynamically connected to the torsion bar (4).

8. A power steering control method and control system for a storage vehicle according to claim 7, characterized in that: The torsion bar (4) is provided with a torque sensor (5) and an angle sensor (6), and the torque sensor (5) and the angle sensor (6) are connected to a power assist system controller (7) via line signals, and the power assist system controller (7) is connected to the power assist device.

9. The power steering control method and control system for a storage vehicle according to claim 7, characterized in that: The power-assisting device comprises a power-assisting motor (8), and the power-assisting motor (8) is dynamically connected to the torsion bar (4) via a speed reduction structure (9).

10. The power steering control method and control system for a storage vehicle according to claim 7, characterized in that: The power assist system controller (7) is signal-connected to a vehicle instrument (10), the vehicle instrument (10) is signal-connected to a vehicle controller (11), and the power assist system controller (7), the vehicle instrument (10), and the vehicle controller (11) are connected to a vehicle power supply (13).

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