Steering control system and vehicle

Abstract

The invention relates to the technical field of vehicle steering control, and discloses a steering control system and a vehicle, the system comprises a main steering module, an auxiliary steering module and a control module, the control module is connected with an electric steering gear of the main steering module, and is connected with an electric power cylinder of the auxiliary steering module, the first steering module is used for providing first steering assistance for the main steering module. The electric power cylinder is used for providing second steering power for the auxiliary steering module; and the control module is connected with the electric steering gear and the electric power-assisted cylinder and used for adjusting the first power-assisted steering according to the steering condition of the main steering module and / or adjusting the second power-assisted steering according to the steering condition of the auxiliary steering module. Steering is electrically controlled, power-assisted steering can be flexibly adjusted, the problem that gaps existing in the transmission process cannot be processed is solved, transmission accuracy and transmission efficiency are improved, steering operation of a driver can be instantly and accurately transmitted to wheels, and control accuracy and sensitivity are remarkably improved.

Description

Technical Field

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

[0002] Currently, the steering systems of construction vehicles, such as wheeled cranes, typically utilize hydraulic power steering. This system typically incorporates a mechanical steering system with a hydraulic booster. The engine drives a power steering pump, converting mechanical energy into hydraulic energy, which in turn drives a hydraulic booster cylinder to rotate the wheels. However, the mechanical structure results in the control mechanism comprising multiple moving parts, resulting in clearances during transmission and difficulty in adjustment. This results in inaccurate transmission and an inability to accurately respond to the driver's steering needs. Summary of the Invention

[0003] In view of this, the present invention provides a steering control system and a vehicle to solve the problem of inaccurate steering control.

[0004] In the first aspect, the present invention provides a steering control system, comprising: a main steering module, an auxiliary steering module and a control module, wherein the control module is connected to the electric steering gear of the main steering module and to the electric power cylinder of the auxiliary steering module, wherein the electric steering gear is used to provide a first steering assist for the main steering module; the electric power cylinder is used to provide a second steering assist for the auxiliary steering module; the control module is connected to the electric steering gear and the electric power cylinder, and is used to adjust the first steering assist according to the steering condition of the main steering module, and / or adjust the second steering assist according to the steering condition of the auxiliary steering module.

[0005] The steering control system provided by the present invention provides steering assistance to the corresponding primary and secondary steering modules through an electric steering gear and an electric power cylinder. The system is connected to a control module, which adjusts the steering assistance based on the operating conditions of the primary and secondary steering modules. By electrically controlling the steering, the present invention can flexibly adjust the steering assistance according to the steering conditions, resolving the issue of unmanageable backlash during transmission. This improves transmission accuracy and efficiency, allowing the driver's steering operations to be instantly and accurately transmitted to the wheels, significantly enhancing control precision and sensitivity.

[0006] In an optional embodiment, the main steering module also includes: a steering wheel, a steering column, an angular actuator, a steering drive shaft, a steering drop arm, a first steering rod, a first steering drive axle, a first angle sensor, a second angle sensor, a third angle sensor and a torque sensor; the steering wheel, the steering column, the angular actuator, the steering drive shaft, the steering drop arm, the electric steering gear, the first steering rod and the first steering drive axle are connected in sequence and are used to drive the first wheel corresponding to the first steering drive axle to steer according to the steering force acting on the steering wheel and the first steering assist force; the first angle sensor is arranged at the input end of the steering column for monitoring the first rotation angle and rotation angular velocity of the steering wheel; the second angle sensor is deployed on the electric steering gear for monitoring the second rotation angle of the electric steering gear input shaft; the torque sensor is deployed on the electric steering gear for monitoring the current torque of the electric steering gear input shaft; the third angle sensor is deployed on the first steering drive axle for monitoring the third rotation angle of the first wheel.

[0007] The present invention installs a transmission device, an angle sensor, and a torque sensor corresponding to the electric steering gear on the main steering module, thereby being able to control the main steering module based on the rotation of the steering wheel and the power assistance of the electric steering gear, thereby improving the sensitivity of directional control based on the steering wheel.

[0008] In an optional embodiment, the control module is connected to the first angle sensor, the second angle sensor and the torque sensor, and adjusts the first steering assist according to the steering condition of the main steering module, including: obtaining the first rotation angle, rotation angular velocity, the second rotation angle, the current torque and the current vehicle speed, and obtaining a predetermined standard steering assist curve and a compensation steering assist curve; calculating the first angle difference between the first rotation angle and the second rotation angle, if the first angle difference is less than or equal to the first preset angle threshold, determining the first steering assist according to the current torque, the current vehicle speed and the standard steering assist curve; if the first angle difference is greater than the first preset angle threshold, determining the first steering assist according to the first rotation angular velocity, the current torque, the current vehicle speed and the compensation steering assist curve.

[0009] The present invention determines the steering assist curve based on the rotation angle of the steering wheel and the rotation angle of the electric steering gear. When a gap exists that makes it impossible for the user to control the steering wheel, the present invention can promptly perform assist compensation, so that the driver's steering operation can be transmitted to the wheels instantly and accurately, significantly improving the accuracy and sensitivity of the control.

[0010] In an optional embodiment, the auxiliary steering module also includes: a steering rocker arm, a second steering rod, a second steering drive axle and a fourth angle sensor; the electric power cylinder, the steering rocker arm, the second steering rod and the second steering drive axle are connected in sequence, and are used to drive the second wheel corresponding to the second steering drive axle to steer according to the steering force and the second steering assist acting on the steering wheel; the fourth angle sensor is deployed on the second steering drive axle to monitor the fourth rotation angle of the second wheel.

[0011] By installing a transmission device and an angle sensor corresponding to the electric power cylinder on the auxiliary steering module, the present invention can drive the rotation of the rear axle based on the rotation of the front axle under the control of the electric power cylinder. No mechanical connection is required between the front and rear axles, the probability of the existence of a gap is reduced, and the response is faster and the transmission efficiency is higher.

[0012] In an optional embodiment, the control module is connected to the third angle sensor and the fourth angle sensor, and adjusts the second steering assist according to the steering condition of the auxiliary steering module, including: obtaining a third rotation angle and a fourth rotation angle; determining a theoretical rotation angle of the second wheel according to the third rotation angle based on a predetermined wheel angle relationship function; calculating a second angle difference between the third rotation angle and the theoretical rotation angle, and determining that the second steering assist is a preset value if the second angle difference is less than or equal to a second preset angle threshold;

[0013] If the second angle difference is greater than the second preset angle threshold, the second steering assist force is adjusted until the second angle difference is less than or equal to the second preset angle threshold.

[0014] The present invention determines the theoretical rotation angle of the rear axle through the rotation angle of the front axle, and can judge whether the rear axle needs to provide steering assistance, and accurately realizes multiple modes including all-wheel steering, crab steering, rear axle locking, and rear axle independent steering.

[0015] In an optional embodiment, the electric power cylinder is also equipped with a stroke sensor; the stroke sensor is used to monitor the cylinder position of the electric power cylinder and send the cylinder position to the control module; the control module calibrates the center position and the extreme position of the electric power cylinder according to the cylinder position and the fourth rotation angle, and adjusts the second steering assist based on the extreme position calibration.

[0016] The present invention can ensure the corresponding accuracy of the electric power-assisted cylinder by calibrating the electric power-assisted cylinder, and further eliminate position deviations caused by mechanical clearance, installation errors, etc.

[0017] In an optional embodiment, the second steering assist is adjusted based on the limit position calibration, including: if the cylinder position exceeds the maximum position or minimum position after the limit position calibration after the electric power cylinder responds to the second steering assist, the second steering assist is reduced.

[0018] The present invention limits the steering assist according to the extreme position calibration, which can reduce the assist output to enhance the hand feel, thereby serving as a warning to the user and ensuring driving safety.

[0019] In an optional embodiment, one end of the electric power cylinder is connected to the vehicle frame, and the other end is connected to the steering rocker arm and is located on the side of the vehicle frame.

[0020] By arranging the electric power-assisting cylinder on the side of the vehicle frame, the present invention can flexibly design the power-assisting torque by adjusting the length of the mechanical arm, compared to arranging it on the steering axle, and reduce the risk of damage that may be caused by road conditions.

[0021] In an optional embodiment, the system further includes: a power supply module and a generator; the power supply module is connected to the generator, and the generator is connected to the electric steering gear and the electric power cylinder to provide power for the electric steering gear and the electric power cylinder.

[0022] By deploying a generator and a power supply module, the present invention can provide power for the electric steering gear and the electric power cylinder, ensuring that the steering system is completed based on electric control and improving the flexibility and accuracy of steering power adjustment.

[0023] In a second aspect, the present invention provides a vehicle comprising: a vehicle frame and a steering control system according to the first aspect or any corresponding embodiment thereof, wherein the vehicle frame comprises a first wheel and a second wheel.

[0024] Because the vehicle includes the steering control system of the above-mentioned first aspect or any corresponding embodiment thereof, it has the same effect as the steering control system and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 is a structural block diagram of a steering control system according to an embodiment of the present invention;

[0027] Figure 2 is a specific structural block diagram of a steering control system according to an embodiment of the present invention;

[0028] Figure 3 is a structural block diagram of a main steering module of a steering control system according to an embodiment of the present invention;

[0029] Figure 4 4 is a structural block diagram of an auxiliary steering module of a steering control system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0031] Embodiments of the present invention are applicable to vehicle steering control scenarios. Vehicle steering control is achieved by transmitting motion and force through mechanical connections in a mechanical transmission. Small, non-operating spaces or looseness between adjacent components, caused by factors such as design, manufacturing, assembly, and wear, are known as mechanical clearance. Therefore, during steering control, when the driver turns the steering wheel, these clearances must be eliminated to steer the wheels and prevent excessive steering wheel free travel (clearance). Clearance is designed to prevent components from becoming stuck (e.g., gears meshing too tightly, preventing rotation). Therefore, small free space is reserved for movement at the joints during design (e.g., the gap between the ball joint and the joint, or the backlash between meshing gears). Normal clearance refers to the calculated clearance at the factory, ensuring flexible rotation without affecting control (similar to the gap between a door hinge and a door frame). Abnormal clearance, on the other hand, refers to the increased clearance caused by component wear over time (e.g., a damaged ball joint boot or a worn gear surface), similar to a "loose screw." When the driver turns the steering wheel, force is transmitted layer by layer through the steering system to the wheels. However, due to the presence of gaps between components, this transfer process occurs in two stages: 1. Eliminating gaps (dead travel). Initially, the steering wheel's force is used to "fill" the gaps between components (for example, tightening the gears and straightening out any slack in the ball joints). During this period, the wheels don't turn, and the driver experiences "steering wheel spin," much like a loose screw that requires several turns before tightening. 2. Inducing wheel rotation (effective travel). Once the gaps are eliminated (components are in close contact), the steering wheel's rotation is mechanically transmitted to the wheels, causing them to actually turn. Only then does the driver's action produce a steering effect, but due to the initial dead travel, the overall steering response is delayed. Steering wheel free travel (free travel) refers to the angle between the steering wheel's initial neutral position and the wheels' initial rotation. For example, a normal vehicle might have 10-15 degrees of free travel (meaning the wheels don't move when the steering wheel is turned 10-15 degrees left or right), while vehicles with excessive free travel may have over 30 degrees of free travel. Therefore, the larger the gap between components, the greater the rotation angle required to "eliminate the gap," resulting in a significant increase in free travel (virtual position). When the driver gently turns the steering wheel, the vehicle does not respond, and a larger turn is required to steer. This prevents the driver's steering operation from being transmitted instantly and accurately to the wheels, reducing the accuracy and sensitivity of the control. Therefore, an embodiment of the present invention provides a steering control system that, through the configuration of an electric steering gear and an electric power steering pump, electrically controls the steering control system, eliminating mechanical backlash and improving steering accuracy.

[0032] According to an embodiment of the present invention, a steering control system embodiment is provided. It should be noted that, as used below, the term "module" may refer to a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation using hardware, or a combination of software and hardware, is also possible and contemplated.

[0033] In this embodiment, a steering control system is provided, which can be used for the above-mentioned vehicles, such as engineering vehicles such as cranes, Figure 1 is a structural block diagram of a steering control system according to an embodiment of the present invention. Figure 1 As shown, the system includes: a main steering module, an auxiliary steering module and a control module, the control module is connected to the electric steering gear of the main steering module, and is connected to the electric power cylinder of the auxiliary steering module, wherein the electric steering gear is used to provide a first steering assist for the main steering module; the electric power cylinder is used to provide a second steering assist for the auxiliary steering module; the control module is connected to the electric steering gear and the electric power cylinder, and is used to adjust the first steering assist according to the steering condition of the main steering module, and / or adjust the second steering assist according to the steering condition of the auxiliary steering module.

[0034] Specifically, in the embodiment of the present invention, Figure 2 As shown, the main steering module mainly controls the steering of the front wheels (the first wheels, usually two) of the vehicle. Figure 3 As shown, the main steering module also includes: a steering wheel, a steering column, an angle actuator, a steering drive shaft, a steering drop arm, a first steering tie rod, a first steering drive axle, a first angle sensor, a second angle sensor, a third angle sensor, and a torque sensor. The steering wheel, steering column, angle actuator, steering drive shaft, steering drop arm, electric steering gear, first steering tie rod, and first steering drive axle are sequentially connected. An electric power cylinder is connected to the vehicle frame at one end and to the steering rocker arm at the other end, located on the side of the vehicle frame, and is configured to steer a first wheel corresponding to the first steering drive axle based on the steering force acting on the steering wheel and the first steering assist force. The first angle sensor is located at the input end of the steering column and is configured to monitor a first rotation angle and angular velocity of the steering wheel. A second angle sensor is located on the electric steering gear and is configured to monitor a second rotation angle of the electric steering gear input shaft. A torque sensor is located on the electric steering gear and is configured to monitor the current torque of the electric steering gear input shaft. A third angle sensor is located on the first steering drive axle and is configured to monitor a third rotation angle of the first wheel.

[0035] In some optional embodiments, the steering wheel, steering column, angle actuator, and steering drive shaft in the main steering module are control mechanisms for the driver to control the steering gear; the steering drop arm and the first steering tie rod (front axle steering tie rod) are the main turning linkage mechanism, and the front axle steering tie rod is used to be articulated with the front axle (first steering drive axle) and can drive the front axle to steer. The electric steering gear is integrated with a controller for calculation and control, the input end is connected to the control mechanism, and the output end is connected to the steering axle through a tie rod. When steering is required, the driver rotates the steering wheel to generate an initial steering torque, which is transmitted to the steering drive shaft through the steering column and then to the electric steering gear. The second angle sensor and torque sensor in the electric steering gear detect the second rotation angle and current torque of the electric steering gear input shaft (corresponding to the steering wheel) and transmit them to the control module (Electric Power Steering Electronic Control Unit, EPSECU). The EPS ECU calculates the required primary steering assist based on signals such as vehicle speed and the secondary steering angle. It then controls the motor to drive the electric steering gear's rack / pinion, which, through the steering drop arm, translates into lateral swing, pushing the primary steering tie rod (i.e., the front axle's steering tie rod). This primary steering tie rod pulls the knuckle arm on the primary steering drive axle (i.e., the front axle), pivoting the wheel about the kingpin. The angle actuator can also participate in secondary adjustments to angle or torque during this phase (e.g., in all-wheel-steer vehicles).

[0036] In some optional embodiments, the auxiliary steering module mainly controls the steering of the rear wheels (the second wheel, usually two) of the vehicle. The auxiliary steering module has many advantages in controlling the steering of the rear wheels. When driving at low speeds, such as parking or turning in a narrow space, the auxiliary steering module can make the rear wheels turn in the opposite direction of the front wheels, effectively reducing the turning radius of the vehicle and improving the flexibility of the vehicle; when driving at high speeds, such as changing lanes at high speed or encountering interference while driving in a straight line, the auxiliary steering module allows the rear wheels to turn in the same direction as the front wheels, which helps to improve the stability and tracking of the vehicle, reduce the impact of side winds on the vehicle, and improve driving safety and comfort. Figure 4 As shown, the auxiliary steering module also includes: a steering rocker arm, a second steering tie rod, a second steering drive axle and a fourth angle sensor; wherein the electric power cylinder, the steering rocker arm, the second steering tie rod and the second steering drive axle are sequentially connected and arranged to drive the second wheel corresponding to the second steering drive axle to steer according to the steering force acting on the steering wheel and the second steering assist force; the fourth angle sensor is deployed on the second steering drive axle to monitor the fourth rotation angle of the second wheel. Figure 4As shown, the electric power cylinder is connected to the vehicle frame at one end and the steering rocker arm at the other. Positioned on the side of the frame, this allows for flexible torque adjustment by adjusting the arm length compared to a system located on the steering axle, while also reducing the risk of damage caused by road conditions. This embodiment of the present invention uses an electric power cylinder to drive and control the rotation of the auxiliary axle wheels, resulting in faster response and higher transmission efficiency than electro-hydraulic auxiliary systems. Furthermore, the electric power cylinder combines the functions of a centering cylinder and a steering cylinder, resulting in a simpler structure.

[0037] In some optional embodiments, the steering rocker arm and the second steering tie rod (auxiliary swivel axle steering tie rod) form an auxiliary swivel linkage mechanism. The auxiliary swivel axle steering tie rod is articulated with the rear axle (secondary steering drive axle) and can drive the rear axle's steering. In this embodiment of the present invention, the front and rear axle steering linkages are not connected by a mechanical structure, but rather by a control module that connects the electric steering gear of the main steering module and the electric power steering pump of the auxiliary steering module. After the front wheels steer under the action of the electric steering gear, the electric power cylinder serves as the power output source for the auxiliary steering module. It receives instructions from the control module and outputs a corresponding thrust or pull based on the steering force applied to the steering wheel and a preset second steering assist strategy. This force is transmitted to the steering rocker arm, which, centered around a fixed fulcrum, converts the linear motion of the electric power cylinder into a swinging motion. Similar to the principle of a lever, this converts the direction and form of force, providing an appropriate power output method for subsequent steering operations. The swinging steering rocker arm further transmits the force to the second steering drive axle (rear axle / auxiliary swivel axle) via the second steering tie rod (rear axle steering tie rod / auxiliary swivel axle steering tie rod). The secondary steering tie rod acts as a connecting bridge, converting the swing of the steering rocker arm into lateral force that propels the secondary steering drive axle. The secondary steering drive axle integrates steering and drive functions. Under the action of lateral force, it drives the corresponding secondary wheel to deflect, achieving vehicle steering.

[0038] In some optional real-time modes, in order to eliminate excess clearance, an embodiment of the present invention respectively provides an electric steering gear and an electric power steering pump in the main steering module and the auxiliary steering module, thereby realizing electric control of the steering control system. This can avoid mechanical connection between the main steering module and the auxiliary steering module, and reduce the impact of mechanical clearance to a certain extent. However, the mechanical clearance inside the main steering module and the auxiliary steering module will still gradually increase with the increase of usage time. Therefore, an embodiment of the present invention adjusts the first steering assist according to the steering condition of the main steering module, and adjusts the second steering assist according to the steering condition of the auxiliary steering module, so as to flexibly adjust the steering assist, so that the free clearance caused by the control mechanism can be compensated at the steering gear input end through the program, thereby compensating for the steering error caused by the mechanical clearance and making the control more precise.

[0039] In some optional embodiments, for the main steering module, the control module is connected to the first angle sensor, the second angle sensor and the torque sensor (eg Figure 2 The first steering angle, angular velocity, second steering angle, current torque, and current vehicle speed are obtained, and a predetermined standard steering assist curve and a compensated steering assist curve are obtained. The assist curve uses the input torque, steering angular velocity, and vehicle speed parameter provided by the ECU as reference variables to determine the steering assist provided. Different steering assists are adapted for low-speed conditions, high-speed conditions, and emergency conditions. The adaptation process is determined based on the first steering angle of the steering wheel and the second steering angle of the electric steering gear. First, a first angle difference between the first and second steering angles is calculated. If the first angle difference is less than or equal to a first preset angle threshold, the standard steering assist curve is used to determine the first steering assist based on the current torque, current vehicle speed, and the standard steering assist curve. If the first angle difference is greater than the first preset angle threshold, it indicates that the steering wheel angle differs significantly from the electric steering angle due to large mechanical clearance, making it impossible to accurately transmit the driver's steering operation to the wheels. Therefore, the compensated steering assist curve is used to determine the first steering assist based on the first angular velocity, current torque, current vehicle speed, and the compensated steering assist curve. The first preset angle threshold can be determined according to the actual steering effect of the vehicle and is not limited here. By adjusting the first preset angle threshold, the steering response speed can be improved and the clearance effect of the control mechanism can be reduced.

[0040] In some optional embodiments, for the auxiliary steering module, the control module is connected to the third angle sensor and the fourth angle sensor (eg Figure 2 (shown by the middle dotted line), thereby obtaining the third rotation angle of the front wheel and the fourth rotation angle of the rear wheel. The embodiment of the present invention pre-sets that the wheel angles corresponding to the front and rear axles satisfy the Ackerman relationship function, that is, according to the Ackerman relationship function, the theoretical rotation angle of the rear wheel can be calculated based on the third rotation angle of the front wheel. Ideally, the actual fourth rotation angle of the rear wheel should be consistent with the calculated theoretical rotation angle, or within the allowable error range. Therefore, the second angle difference between the third rotation angle and the theoretical rotation angle is calculated. If the second angle difference is less than or equal to the second preset angle threshold, it proves that it is within the allowable error range and no additional steering assist is required at this time, that is, the second steering assist is determined to be a preset value (for example, zero). If the second angle difference is greater than the second preset angle threshold, it proves that the steering error of the rear wheel is large at this time, so the second steering assist is adjusted until the second angle difference is less than or equal to the second preset angle threshold. At this time, through the steering assist adjustment of the main steering module and the auxiliary steering module, it can be ensured that both the front and rear wheels can achieve relatively precise steering control, and the steering error caused by mechanical clearance is eliminated to the greatest extent.

[0041] In some optional implementations, in some wheeled machines, due to the long transmission path of their control mechanisms, once key mechanical transmission components such as the angle steering gear become disconnected due to an accident, the safety of the steering system will face severe challenges. However, in the embodiments of the present invention, steering control is performed using an electric steering gear and an electric power cylinder. Under the precise control of the program, the steering gear can still maintain the dynamic tracking capability of the steering wheel angle changes. Even if the mechanical connection fails, the system can continue to output steering commands through the electronic compensation algorithm, ensuring that the vehicle has basic steering control functions, thereby helping the vehicle to achieve short-distance movement in emergency situations, greatly improving the vehicle's controllability under extreme conditions, and buying valuable time for subsequent rescue and disposal work.

[0042] In some optional embodiments, the electric power cylinder is further equipped with a stroke sensor. A stroke sensor is a sensor used to detect the displacement (stroke) or position change of a mechanical component. In this embodiment of the present invention, it is used to monitor the cylinder position of the electric power cylinder and transmit the cylinder position to the control module. The control module calibrates the electric power cylinder to its neutral position and extreme position based on the cylinder position and the fourth rotation angle, and adjusts the second steering assist based on the extreme position calibration.

[0043] In some optional embodiments, the center calibration is intended to determine the "zero position" of the electric power cylinder, that is, the standard position of the electric power cylinder when the vehicle is traveling in a straight line. The specific steps are as follows: ① Initial condition setting: The vehicle is stationary and the steering wheel is in the middle position (straight-line driving state). At this time, the second wheel should remain facing forward. ② Data acquisition and analysis: The control module reads the data of the current cylinder position sensor and the fourth angle sensor. If the data of both are not at the standard value (theoretically, the cylinder is in the middle position when traveling in a straight line, and the fourth rotation angle is 0° or a specific angle corresponding to the center position), the current deviation is recorded. ③ Calibration adjustment: The control module calculates the displacement that needs to be adjusted for the electric power cylinder based on the deviation, sends a control signal to the electric power cylinder, drives the piston to move to the center standard position, and completes the center calibration. Center calibration can ensure that subsequent steering operations are based on the accurate center position, avoiding steering offset due to initial position deviation.

[0044] In some optional embodiments, the extreme position calibration is used to determine the maximum extension and retraction position of the electric power cylinder to prevent it from exceeding the safe working range. The specific operations are as follows: ① Limit test trigger: The control module first controls the electric power cylinder to slowly extend, while monitoring the cylinder position sensor data and the fourth angle sensor data in real time. When the second wheel reaches the maximum steering angle (i.e., the steering limit of the vehicle design) and the fourth turning angle reaches the preset maximum angle threshold, the control module records the cylinder position at this time as the maximum extension limit position. ② Reverse test: Control the electric power cylinder to retract, repeat the above monitoring process, and when the second wheel reaches the maximum steering angle on the other side, record the cylinder position at this time as the maximum retraction limit position. ③ Data storage and verification: The maximum extension and retraction position data are stored in the memory of the control module, and multiple tests and verifications are performed to ensure the accuracy and consistency of the extreme position data. Extreme position calibration not only protects the electric power cylinder and steering system components, but also provides boundary conditions for subsequent power adjustment.

[0045] In some optional embodiments, after completing the extreme position calibration, the control module optimizes and adjusts the second steering assist based on the extreme position data to improve steering performance and safety. For example, optimization can be performed based on the assist curve: the control module replans the second steering assist output curve based on the extreme position. Approaching the extreme position (maximum or minimum), the assist output is appropriately reduced to allow the driver to more clearly perceive steering resistance and avoid oversteering due to excessive assist. Within the normal steering range, the assist output is maintained at a reasonable level to ensure smooth steering. Alternatively, a safety threshold can be set: based on the extreme position, a safety threshold for assist output is set. When the second wheel approaches the extreme steering angle, if the control module detects abnormal steering force or speed changes, the assist output of the electric power cylinder may be limited or even cut off to prevent the risk of vehicle loss of control due to oversteering. Alternatively, adaptive adjustment can be performed: the control module dynamically adjusts the second steering assist based on vehicle driving conditions (such as speed and road conditions) and extreme position data. For example, at high speeds, the assist adjustment may be more conservative near the extreme position to enhance vehicle stability; at low speeds, the assist adjustment range may be appropriately relaxed to improve steering flexibility. Through the above-mentioned mid-position calibration, extreme position calibration and power assist adjustment processes, the control module can accurately control the working state of the electric power assist cylinder, so that the second steering assist is highly matched with the vehicle steering requirements, thereby improving the vehicle steering accuracy, safety and driving comfort.

[0046] In some optional embodiments, such as Figure 2 As shown, the steering control system also includes: a power supply module and a generator; wherein the power supply module is an emergency battery connected to the generator, and the generator is connected to the electric steering gear and the electric power cylinder (such as Figure 2The electric power steering system (shown by the solid line) is used to provide power to the electric steering gear and the electric power cylinder.

[0047] The steering control system provided by the present invention provides steering assistance to the corresponding primary and secondary steering modules through an electric steering gear and an electric power cylinder. The system is connected to a control module, which adjusts the steering assistance based on the operating conditions of the primary and secondary steering modules. By electrically controlling the steering, the present invention can flexibly adjust the steering assistance according to the steering conditions, resolving the issue of unmanageable backlash during transmission. This improves transmission accuracy and efficiency, allowing the driver's steering operations to be instantly and accurately transmitted to the wheels, significantly enhancing control precision and sensitivity.

[0048] The present invention also provides a vehicle, such as an engineering vehicle such as a wheeled crane, comprising: a frame and the above-mentioned Figure 1 The steering control system shown is configured such that the vehicle frame includes a first wheel and a second wheel.

[0049] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A steering control system comprising: The main steering module, the auxiliary steering module and the control module are characterized in that the control module is connected to the electric steering gear of the main steering module and to the electric power cylinder of the auxiliary steering module, wherein: The electric steering gear is used to provide a first steering assist for the main steering module; The electric power-assisting cylinder is used to provide a second steering assist for the auxiliary steering module; The control module is connected to the electric steering gear and the electric power cylinder, and is used to adjust the first steering assist according to the steering condition of the main steering module, and / or adjust the second steering assist according to the steering condition of the auxiliary steering module.

2. The system according to claim 1, wherein: The main steering module further includes: a steering wheel, a steering column, an angle actuator, a steering transmission shaft, a steering drop arm, a first steering tie rod, a first steering drive axle, a first angle sensor, a second angle sensor, a third angle sensor and a torque sensor; The steering wheel, the steering column, the angle actuator, the steering transmission shaft, the steering drop arm, the electric steering gear, the first steering tie rod and the first steering drive axle are sequentially connected and configured to drive the first wheel corresponding to the first steering drive axle to steer according to the steering force acting on the steering wheel and the first steering assist force; The first angle sensor is arranged at the input end of the steering column, and is used to monitor the first rotation angle and rotation angular velocity of the steering wheel; The second angle sensor is disposed on the electric steering gear and is used to monitor a second rotation angle of an input shaft of the electric steering gear; The torque sensor is disposed on the electric steering gear and is used to monitor the current torque of the electric steering gear input shaft; The third angle sensor is disposed on the first steering drive axle and is used to monitor a third rotation angle of the first wheel.

3. The system according to claim 2, characterized in that The control module is connected to the first angle sensor, the second angle sensor, and the torque sensor, and adjusting the first steering assist according to the steering condition of the main steering module includes: acquiring the first rotation angle, the rotation angular velocity, the second rotation angle, the current torque, and the current vehicle speed, and acquiring a predetermined standard steering power-assistance curve and a compensated steering power-assistance curve; calculating a first angle difference between the first rotation angle and the second rotation angle, and if the first angle difference is less than or equal to a first preset angle threshold, determining the first steering assist according to the current torque, the current vehicle speed, and the standard steering assist curve; If the first angle difference is greater than the first preset angle threshold, the first steering assist force is determined according to the first rotational angular velocity, the current torque, the current vehicle speed, and the compensated steering assist force curve.

4. The system according to claim 2, wherein: The auxiliary steering module further includes: a steering rocker arm, a second steering tie rod, a second steering drive axle and a fourth angle sensor; The electric power cylinder, the steering rocker arm, the second steering tie rod and the second steering drive axle are sequentially connected and configured to drive the second wheel corresponding to the second steering drive axle to steer according to the steering force acting on the steering wheel and the second steering assist force; The fourth angle sensor is disposed on the second steering drive axle and is used to monitor a fourth rotation angle of the second wheel.

5. The system according to claim 4, characterized in that The control module is connected to the third angle sensor and the fourth angle sensor, and adjusting the second steering assist according to the steering condition of the auxiliary steering module includes: Acquiring a third rotation angle and the fourth rotation angle; determining a theoretical rotation angle of the second wheel according to the third rotation angle based on a predetermined wheel angle relationship function; calculating a second angle difference between the third rotation angle and the theoretical rotation angle, and determining that the second steering assist force is a preset value if the second angle difference is less than or equal to a second preset angle threshold; If the second angle difference is greater than the second preset angle threshold, the second steering assist force is adjusted until the second angle difference is less than or equal to the second preset angle threshold.

6. The system according to claim 4, characterized in that The electric booster cylinder is also equipped with a stroke sensor; The stroke sensor is used to monitor the cylinder position of the electric power cylinder and send the cylinder position to the control module; The control module performs mid-position calibration and extreme position calibration on the electric power cylinder according to the cylinder position and the fourth rotation angle, and adjusts the second steering assist based on the extreme position calibration.

7. The system according to claim 6, characterized in that The adjusting the second steering assist based on the limit position calibration includes: If the oil cylinder position exceeds the maximum position or the minimum position after the limit position is calibrated after the electric power cylinder responds to the second steering assist, the second steering assist is reduced.

8. The system according to claim 4, wherein: One end of the electric power cylinder is connected to the vehicle frame, and the other end is connected to the steering rocker arm and is located on the side of the vehicle frame.

9. The system according to claim 1, wherein: Also includes: Power supply modules and generators; The power supply module is connected to the generator, and the generator is connected to the electric steering gear and the electric power cylinder, and is used to provide power to the electric steering gear and the electric power cylinder.

10. A vehicle, characterized in that: include: A vehicle frame and the steering control system according to any one of claims 1 to 9, wherein the vehicle frame includes a first wheel and a second wheel.

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