Four-wheel independent motor drive articulated vehicle steering control method and device and vehicle

Abstract

The application discloses a four-wheel independent motor driving articulated vehicle steering control method and device and a vehicle. The four-wheel independent motor driving articulated vehicle steering control method comprises the following steps: detecting the current steering angle, vehicle speed, displacement direction and size of a valve core of a steering valve of the whole machine in real time; calculating a four-wheel differential auxiliary steering control signal according to the current steering angle, vehicle speed, displacement direction and size of the valve core of the steering valve of the whole machine, and outputting the four-wheel differential auxiliary steering control signal according to a set control strategy, so as to assist the hydraulic system in steering, thereby improving the unstable shaking of the whole machine when starting and stopping steering, reducing the impact when stopping steering, reducing the steering energy consumption, and keeping the hydraulic steering and the differential auxiliary steering synchronous.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of engineering vehicles, and particularly relates to a four-wheel independent motor driving articulated vehicle steering control method and device and vehicle. BACKGROUND

[0002] In the prior art, a large-tonnage articulated steering loader adopts a front and rear four-wheel edge independent motor driving speed reducer driving walking scheme, and four wheel edge motors are powered and driven to walk through large-capacity batteries or engine direct-drive generators. The steering system is a hydraulic flow amplification steering system. Due to the large weight (50t~300t) of the vehicle itself and the load under the condition, the differential auxiliary hydraulic system is driven to steer when steering. However, the following problems still exist during walking and steering: the steering hydraulic cylinder action and the motor driven wheel differential action are out of synchronization at the initial stage of steering start, the motor differential responds first, at this time the cylinder control valve has not yet been actuated, the cylinder is in a locked state, the steering cylinder is momentarily pressurized, and then the cylinder is actuated by the opening of the steering cylinder control valve. Due to the out-of-synchronization of the two actions, the vehicle is not stable during steering start, the vehicle shaking during steering is increased, the driving comfort is reduced, and there is a certain energy loss and tire wear. Or the motor driven wheel differential action is later than the steering cylinder action, at this time the steering hydraulic system drags the motor driven wheel to rotate, the steering cylinder pressure rises rapidly, and then the motor driven wheel differential starts to assist steering. At the moment of motor driven wheel differential action, the machine steering also appears unstable and shaking phenomenon. Since the cab is high (2m~8m), the shaking will be amplified in the cab, the driving comfort is reduced, and there is a certain energy loss and tire wear. The left and right steering limit positions are generally hard limit or rubber pad limit. When the differential auxiliary steering stops at the left and right limit angles, the stopping impact is increased, the vehicle shaking is increased, and the impact on the articulated position is large. Long-term and repeated severe impact reduces the fatigue strength of the articulated position of the front and rear frames, affects the long-term reliability, and the like. SUMMARY

[0003] To solve the problems in the prior art, the present application provides a four-wheel independent motor driving articulated vehicle steering control method, device and vehicle, which improves the unstable shaking of the machine during steering start and stop, reduces the impact during steering stop, reduces the steering energy consumption, and reduces the tire wear caused by the out-of-synchronization of hydraulic steering and differential auxiliary steering.

[0004] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0005] In a first aspect, a four-wheel independent motor-driven articulated vehicle steering control method is provided, comprising: detecting in real time a current steering angle, a vehicle speed, a spool displacement direction and size of a steering valve of the whole machine; calculating a four-wheel differential auxiliary steering control signal according to the current steering angle, the vehicle speed, the spool displacement direction and size of the steering valve of the whole machine, and outputting the four-wheel differential auxiliary steering control signal according to a set control strategy, for assisting the hydraulic system steering, so as to improve the instability and shaking of the whole machine when starting and stopping steering, reduce the impact when stopping steering, reduce the steering energy consumption, and keep the hydraulic steering and the differential auxiliary steering synchronized.

[0006] Further, the vehicle adopts a load-sensitive pump steering system, the steering mode is steering by a steering wheel and / or an electrically-controlled steering handle, and the steering valve is a common steering valve or a flow amplification valve.

[0007] Further, the outputting of the four-wheel differential control signal according to the set control strategy comprises: after the steering wheel or the electrically-controlled steering handle is actuated, the main controller detects a current steering angle of the whole machine. When the steering angle is greater than a first set angle value and less than a second set angle value, the main controller outputs the four-wheel differential auxiliary steering control signal. Meanwhile, the spool of the steering valve is actuated, and the main controller detects a spool displacement direction d and a displacement size Δt of the steering valve. When the displacement size Δt is 0, the main controller does not output the four-wheel differential auxiliary steering control signal or stops the signal output. When the displacement size Δt is not 0, the main controller calculates and outputs the four-wheel differential auxiliary steering control signal according to the current vehicle speed, for assisting the hydraulic system steering. When the steering angle is not greater than the first set angle value or is not less than the second set angle value, the main controller stops outputting the four-wheel differential auxiliary steering control signal, and the steering is continued by relying on the steering hydraulic system and the mass inertia of the whole machine until the steering wheel or the electrically-controlled steering handle stops steering or the main controller detects a limit angle signal of the articulated position angle sensor to stop steering or the vehicle frame hits the limiting device to stop steering. The first set angle value represents a set angle value, the second set angle value represents a left-right steering limit angle of the whole vehicle, and

[0008] the other set angle value represents another set angle value. Further, the outputting of the four-wheel differential control signal according to the set control strategy further comprises: when the steering angle When the steering valve core displacement direction d and displacement magnitude Δt are within the specified range, the main controller detects the displacement direction d and displacement magnitude Δt of the steering valve core and determines whether the displacement direction d and displacement magnitude Δt are 0. When the signal is 0, the main controller outputs no four-wheel differential auxiliary steering control signal or a stop signal. When the signal is not 0, the next action is determined based on the detected steering system pressure p. When the steering system pressure p is not within the pressure range of (A-Δp, A), the main controller outputs no four-wheel differential auxiliary steering control signal. When A-Δp≤p≤A, the main controller calculates and outputs the four-wheel differential auxiliary steering control signal based on the current vehicle speed and then continues to detect the current steering angle of the entire machine. rate of change ,when When the value is not 0, the machine will exhibit a steering action and continue to turn. When the value is 0, the main controller outputs a four-wheel differential auxiliary steering control signal until the entire machine begins to steer; where A represents the high-pressure overflow pressure set by the steering system, and Δp represents a set pressure difference value.

[0009] Furthermore, the vehicle employs an electronically controlled pump steering system, with steering via a steering wheel and / or an electronically controlled steering handle, and the steering valve is either a standard steering valve or a flow amplification valve.

[0010] Furthermore, according to the set control strategy, the four-wheel differential control signal is output, including: the main controller detects the angle sensor signal of the steering wheel or the electric steering handle; when the electrical signal of the angle sensor of the steering wheel or the electric steering handle is 0, the output flow of the electric pump is 0 or maintains a standby flow, and the whole machine has no steering action or the steering stops.

[0011] Furthermore, the output of four-wheel differential control signals according to the set control strategy also includes: when the electrical signal of the angle sensor of the steering wheel or electronic steering handle is not zero, the main controller detects the current steering angle of the entire machine. When the steering angle satisfy: Simultaneously, the steering valve spool actuates, and the main controller detects whether the displacement direction d and displacement magnitude Δt of the steering valve spool are zero. When the signal is zero, the main controller outputs no four-wheel differential auxiliary steering control signal or a stop signal. When the signal is not zero, the main controller calculates and outputs a four-wheel differential auxiliary steering control signal based on the current vehicle speed to assist the hydraulic system in steering. At the same time, the main controller continuously monitors the current steering angle of the entire machine. ,when or When the steering angle is not in the range, the main controller stops outputting the four-wheel differential auxiliary steering control signal, at which time the steering continues to rely on the steering hydraulic system and the mass inertia of the whole machine until the steering wheel or the electric control steering handle stops steering or the main controller stops steering when detecting the limit angle signal of the articulation position angle sensor or the vehicle frame stops steering when hitting the limiting device; wherein, represents a set angle value, represents the left and right steering limit angle of the whole vehicle, represents another set angle value.

[0012] Further, the four-wheel differential control signal output according to the set control strategy also includes: when the steering angle is not in the range , the main controller detects the displacement direction d and the displacement size Δt of the valve core of the steering valve, and judges whether the displacement direction d and the displacement size Δt are 0, when the signal is 0, the main controller has no four-wheel differential auxiliary steering control signal output or stops signal output, when the signal is not 0, according to the detected steering system pressure p to determine the next action, when the steering system pressure p is not in the pressure range (A-Δp, A), the main controller has no four-wheel differential auxiliary steering control signal output, when A-Δp≤p≤A, the main controller calculates the four-wheel differential auxiliary steering control signal according to the current vehicle speed state and outputs, and then continues to detect the change rate of the steering angle of the whole machine, when is not 0, the whole machine appears steering action and continues to steer, when is equal to 0, the main controller outputs the four-wheel differential auxiliary steering control signal until the whole machine starts to steer; wherein A represents the set high pressure overflow pressure of the steering system, and Δp represents a set pressure difference value.

[0013] In the second aspect, a four-wheel independent motor driven articulated vehicle steering control device is provided, comprising: a data acquisition module for real-time detection of the current steering angle, vehicle speed, displacement direction and size of the valve core of the steering valve of the whole machine; an auxiliary steering module for calculating the four-wheel differential auxiliary steering control signal according to the current steering angle, vehicle speed, displacement direction and size of the valve core of the steering valve of the whole machine, and outputting the four-wheel differential auxiliary steering control signal according to the set control strategy, for assisting the hydraulic system to steer, so as to improve the unstable shaking of the whole machine at the steering start and stop, reduce the impact at the steering stop, reduce the steering energy consumption and keep the hydraulic steering and differential auxiliary steering synchronous.

[0014] In the third aspect, a four-wheel independent motor driven articulated vehicle is provided, which is configured with the four-wheel independent motor driven articulated vehicle steering control device of the second aspect.

[0015] Compared with the prior art, the present application has the beneficial effects: according to the current steering angle, vehicle speed, valve core displacement direction and size of the steering valve of the whole machine, the four-wheel differential auxiliary steering control signal is calculated and obtained, and the four-wheel differential auxiliary steering control signal is output according to the set control strategy, which is used for auxiliary hydraulic system steering, improves the unstable shaking of the whole machine during steering start and steering stop, reduces the impact during steering stop, reduces the steering energy consumption, and reduces the tire wear problem caused by the asynchronization of hydraulic steering and differential auxiliary steering. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is the steering system principle schematic diagram of the four-wheel independent motor driven articulated vehicle in the embodiment of the present application;

[0017] Figure 2 is the main flow schematic diagram of the four-wheel independent motor driven articulated vehicle steering control method provided by the embodiment of the present application;

[0018] Figure 1 In the middle: 1, hydraulic oil tank; 2, steering pump; 3, steering valve; 31, valve core displacement sensor; 4, steering oil cylinder; 5, steering wheel; 6, angle sensor; 7, steering gear; 8, electric control steering handle; 9, electric control steering pilot valve; 10, pressure sensor. DETAILED DESCRIPTION

[0019] The present application will be further described below in combination with the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and cannot be used to limit the protection scope of the present application.

[0020] Embodiment one

[0021] The main structure of the four-wheel independent motor driven articulated vehicle in the present application includes: front frame, rear frame, four wheel edge drive motors and four wheel edge drive motor reducers respectively arranged on the front frame and the rear frame, four wheel assemblies, four drive motor controllers; further including a main controller, a front and rear frame hinged position angle sensor; as Figure 1Also shown, further comprising: a steering pump 2 (electric control plunger pump or load sensitive plunger pump), a pressure sensor 10 arranged at the outlet of the steering pump 2, a steering wheel 5 matched with a hydraulic control steering gear 7 with an angle sensor 6 or an electric control steering handle 8 (integrated angle sensor), an electric control steering pilot valve 9 (used with the electric control steering handle 8), a steering valve 3 (ordinary steering valve or steering flow amplification valve, configured with a valve core displacement sensor 31), a steering cylinder 4. The inlet of the steering pump 2 is connected to the hydraulic oil tank 1, the outlet of the steering pump 2 is connected to the P port of the steering valve 3, the T port of the steering valve 3 is connected to the hydraulic oil tank 1, the CR port and the CL port of the steering valve 3 are connected to the steering cylinder 4; the L port of the steering valve 3 is respectively connected to the L port of the steering gear 7 and the L port of the electric control steering pilot valve 9; the R port of the steering valve 3 is respectively connected to the R port of the steering gear 7 and the R port of the electric control steering pilot valve 9; the input end of the steering gear 7 is connected to the angle sensor 6 and the steering wheel 5; the input end of the electric control steering pilot valve 9 is connected to the electric control steering handle 8.

[0022] The displacement sensor is integrated on the main valve stem of the steering valve 3 (common steering valve or flow amplification type steering valve), the main controller detects the valve core displacement sensor signal of the steering valve 3 to determine the valve core displacement information, including the valve core displacement direction and the displacement size, the valve core displacement direction can determine the steering direction, the valve core displacement size can determine the valve core opening size, the larger the displacement, the larger the valve core opening, the larger the flow of the steering oil cylinder 4, the faster the steering speed, the larger the valve opening, the faster the steering speed expected by the driver. According to the valve core displacement sensor signal and the vehicle speed signal, the main controller calculates the required differential speed of the four wheels, and controls the motor controller to output the control voltage corresponding to the required differential speed to the four motors to obtain the differential torque, and completes the differential auxiliary steering control. After detecting the displacement signal of the valve core displacement sensor 31 of the steering valve 3 and the vehicle speed signal, the main controller will output the differential control voltage to the four motors within 100ms (main controller response time), the wheel differential action and the steering oil cylinder 4 action are almost synchronous (the faster the main controller response, the more synchronous the differential auxiliary steering and hydraulic steering), avoiding the energy loss, unstable starting process and tire wear caused by the out-of-sync control action of the two. At the same time, the steering angle is detected, the steering limit angle of the articulated vehicle at the middle position is generally less than or equal to 45°, when the steering is detected to be close to the left and right limit positions, the wheel differential auxiliary steering is stopped, and the steering oil cylinder continues to act and the inertia of the whole vehicle makes the whole vehicle turn to the left and right limit positions, and hits the limit to stop steering or the main controller stops steering according to the limit angle signal of the articulated position angle sensor, at this time the differential auxiliary stops when the whole vehicle has not turned to the limit angle, which can reduce the impact force when the front and rear frames are suddenly stopped when the articulated position is turned to the limit, thereby improving the durability of the articulated position and reducing the shaking of the whole vehicle, improving driving comfort and energy utilization. When the steering angle of the whole vehicle is near the limit angle, the main controller detects the steering hydraulic system pressure, when the pressure is lower than the set pressure value (less than the system maximum pressure), only the hydraulic system steering is used; when the pressure is higher than this value and lower than the system set maximum overflow pressure, the main controller only provides lower differential torque to assist steering, while detecting the change of the whole vehicle angle and dynamically increasing the differential auxiliary steering torque to make the whole machine turn. It can reduce the impact and damage to the articulated frame when the steering is turned to the limit position and stopped instantly, and the wear of the tire caused by the delay of the differential stop, and also reduce the energy loss.

[0023] A steering control method for a four-wheel independent motor driven articulated vehicle includes: real-time detection of the vehicle's current steering angle, vehicle speed, and the direction and magnitude of the steering valve core displacement; calculation of a four-wheel differential auxiliary steering control signal based on the vehicle's current steering angle, vehicle speed, and the direction and magnitude of the steering valve core displacement; and outputting the four-wheel differential auxiliary steering control signal according to a set control strategy to assist the hydraulic system steering, thereby improving the vehicle's unstable swaying during steering start-up and steering stop, reducing the impact during steering stop, reducing steering energy consumption, and maintaining synchronization between hydraulic steering and differential auxiliary steering.

[0024] like Figure 1 , Figure 2 As shown, when the steering system is a load-sensitive pump steering system, and the steering method is steering wheel, electric steering lever, or both, an angle sensor 6 is not required between the steering wheel 5 and the steering gear 7. When the steering valve 3 is a standard steering valve, the steering gear 7 used in this case is a steering gear without an LS signal output port. When the steering wheel 5 rotates, it drives the shaft of the steering gear 7 to rotate. The L or R port of the steering gear 7 outputs a left or right steering pilot hydraulic signal to the steering valve 3, controlling the movement of the valve core of the steering valve 3. This causes the valve core displacement sensor 31 to activate and output an electrical signal. After the valve core moves, it connects the steering pump 2 and the steering cylinder 4. At the same time, the load-sensitive steering pump receives the high-pressure hydraulic signal from the steering cylinder transmitted by the steering valve 3 and performs variable displacement control. The steering cylinder 4 begins to move. The faster the steering wheel 5 rotates, the greater the displacement of the valve core, the greater the displacement of the load-sensitive pump, and the faster the overall vehicle steering speed. Similarly, the slower the steering wheel rotates, the slower the overall vehicle steering speed. When steering valve 3 is a regular steering valve and the steering method is electric steering handle, the electric steering handle outputs different electrical signals to the electric steering pilot valve after moving left or right. After receiving the electrical signal, the electric steering pilot valve activates and outputs pilot oil to the steering valve through its L or R port, controlling the steering valve 3 to move. The steering valve 3 then activates the valve core displacement sensor 31 and outputs an electrical signal. After the steering valve 3 moves, the steering pump 2 is connected to the steering cylinder 4, and the steering cylinder 4 begins to move. At the same time, the load-sensitive steering pump receives the high-pressure oil signal from the steering cylinder transmitted by the steering valve 3 and performs variable displacement control. The larger the angle of rotation of the electric steering handle, the greater the displacement of the steering valve core, the greater the displacement of the load-sensitive pump, and the faster the vehicle steering speed. Similarly, the smaller the rotation angle of the electric steering lever, the slower the vehicle's steering speed. Steering wheel steering and electric steering lever steering can coexist, achieved by connecting the L and R ports of the steering gear 7 in parallel with the L and R ports of the electric steering pilot valve 9, and then connecting them to the L and R ports of the steering valve 3.

[0025] When the steering valve 3 is a flow amplification type steering valve, the steering gear with LS signal port is used when the steering wheel is steered. When the steering wheel 5 rotates, the steering gear 7 is rotated, and the L or R port of the steering gear 7 outputs a left or right steering pilot oil signal to the L or R port of the flow amplification type steering valve. At the same time, the LS oil signal of the steering gear is transmitted to the flow amplification type steering valve and the load sensing steering pump, controlling the movement of the valve core of the flow amplification type steering valve, and driving the valve core displacement sensor 31 to act and output an electric signal. After the movement of the valve core, the steering pump 2 and the steering cylinder 4 are connected, and the steering cylinder 4 starts to act. The faster the steering wheel 5 rotates, the greater the displacement of the valve core, and the greater the displacement of the load sensing pump, and the faster the steering speed of the whole vehicle. Similarly, the slower the steering wheel rotates, the slower the steering speed of the whole vehicle. When the steering mode is electric control steering handle steering, the electric control steering handle rotates to the left or right and outputs different electric signals to the electric control steering pilot valve. After receiving the electric signal, the electric control steering pilot valve acts, and the L or R port of the electric control steering pilot valve outputs a corresponding pilot oil to the L or R port of the flow amplification type steering valve. At the same time, the LS oil signal of the electric control steering pilot valve is transmitted to the flow amplification type steering valve and the load sensing steering pump, controlling the movement of the valve core of the flow amplification type steering valve, and driving the valve core displacement sensor to act and output an electric signal. After the movement of the valve core, the steering pump and the steering cylinder are connected, and the steering cylinder starts to act. The greater the angle of the electric control steering handle, the greater the displacement of the valve core of the flow amplification type steering valve, and the greater the displacement of the load sensing pump, and the faster the steering speed of the whole vehicle. Similarly, the smaller the angle of the electric control steering handle, the slower the steering speed of the whole vehicle. The steering wheel steering and the electric control steering handle steering can also coexist, and the L, R and LS ports of the steering gear are connected in parallel with the L, R and LS ports of the electric control steering pilot valve, and then connected to the L, R and LS ports of the flow amplification valve.

[0026] As shown in Figure 2 The above load sensing pump steering system with ordinary steering valve or flow amplification type steering valve, when the steering wheel or electric control steering handle acts, the main controller detects the current steering angle of the whole machine When the steering angle satisfies: Meanwhile, the diverter or the electrically controlled steering pilot valve is actuated, the main valve core of the steering valve is actuated after the steering valve receives the LS and L or R hydraulic oil signals, meanwhile, the proportional output flow is given to the steering valve by the load sensing pump after the load sensing pump receives the pilot LS oil pressure signal from the steering valve or the diverter or the electrically controlled steering pilot valve, the main controller detects the displacement direction and size signals of the displacement sensor of the steering valve, and judges whether the displacement direction d and the displacement size Δt are 0, when the signals are 0, the main controller does not output or stops outputting the four-wheel differential auxiliary steering control signal, when the signals are not 0, the main controller calculates and outputs the four-wheel differential auxiliary steering control signal according to the current vehicle speed, which is used to assist the steering of the hydraulic system; meanwhile, the main controller detects the current steering angle of the whole machine in real time When or , the main controller stops outputting the four-wheel differential auxiliary steering control signal, at this time, the steering relies on the steering hydraulic system and the mass inertia of the whole machine to continue steering until the steering wheel or the electrically controlled steering handle stops steering or the main controller stops steering when detecting the limit angle signal of the hinged position angle sensor or the vehicle frame stops steering when hitting the limiting device; wherein represents a set angle value, , represents the left and right steering limit angles of the whole vehicle, represents another set angle value, When the steering angle is not in the range of , the diverter or the electrically controlled steering pilot valve is actuated, and then the main valve core of the steering valve is actuated after the steering valve receives the LS hydraulic oil signal, meanwhile, the proportional output flow is given to the steering valve by the load sensing pump after the load sensing pump receives the pilot LS oil pressure signal from the steering valve or the diverter or the steering pilot valve, the main controller detects the displacement direction d and the displacement size Δt of the valve core of the steering valve, and judges whether the displacement direction d and the displacement size Δt are 0, when the signals are 0, the main controller does not output or stops outputting the four-wheel differential auxiliary steering control signal, when the signals are not 0, the next action is determined according to the detected steering system pressure p, when the steering system pressure p is not in the pressure range of (A-Δp, A), the main controller does not output the four-wheel differential auxiliary steering control signal, when A-Δp≤p≤A, the main controller calculates and outputs the weakened four-wheel differential auxiliary steering control signal according to the current vehicle speed state (the weakened four-wheel differential auxiliary steering control signal can be 1 / 10, 1 / 5, 1 / 4, 1 / 3, 1 / 2……, or other certain fixed value, etc. of the calculated value), then, the change rate of the current steering angle of the whole machine is detected , when When equal to 0, the main controller outputs enhanced four-wheel differential auxiliary steering control signal (enhanced method including: enhanced in equal ratio series, such as enhanced signal can be 1.1 times, 1.2 times, 1.3 times of the weakening signal; enhanced in equal difference series, such as enhanced signal can be the current weakening signal plus a certain fixed value; enhanced in other function form, etc.), until the whole machine steering can rotate and continue to steer; wherein, A represents the high pressure overflow pressure set by the steering system, Δp represents a set pressure difference, 0Mpa < Δp ≤ 8Mpa.

[0027] Example two

[0028] The difference between this embodiment and example one is that the electric control pump steering system is used in this embodiment, the steering mode is steering by steering wheel or electric control steering handle or coexistence of the two steering modes, at this time the angle sensor needs to be connected between the steering wheel and the steering gear, and the steering valve is a common steering valve or a flow amplification valve.

[0029] When the steering valve is a common steering valve, the steering gear used at this time is a steering gear without LS signal output port, when the steering wheel rotates, the angle sensor and the steering gear shaft rotate, the L or R port of the steering gear outputs left or right steering pilot oil signal to the steering valve, controls the movement of the valve core of the steering valve, and drives the valve core displacement sensor to act and output an electric signal, after the movement of the valve core, the steering pump and the steering oil cylinder are connected, at the same time, the electric control steering pump receives the angle sensor electric signal of the steering wheel for variable displacement control, the steering oil cylinder starts to act, the faster the steering speed of the steering wheel, the greater the displacement of the electric control pump, and the faster the steering speed of the whole vehicle. Similarly, the slower the steering speed of the steering wheel, the slower the steering speed of the whole vehicle; when the steering valve is a common steering valve and the steering mode is electric control steering handle steering, the electric control steering handle outputs different electric signals to the electric control steering pilot valve after moving left or right, the electric control steering pilot valve acts according to the received electric signal, the L or R port of the electric control steering pilot valve outputs corresponding pilot oil to the steering valve, controls the movement of the steering valve, and drives the valve core displacement sensor to act and output an electric signal, after the movement of the steering valve, the steering pump and the steering oil cylinder are connected, at the same time, the electric control steering pump receives the rotation angle electric signal of the electric control steering handle for variable displacement control, the steering oil cylinder starts to act, the greater the angle of the electric control steering handle, the greater the displacement of the electric control pump, and the faster the steering speed of the whole vehicle. Similarly, the smaller the rotation angle of the electric control steering handle, the slower the steering speed of the whole vehicle; the steering wheel steering and the electric control steering handle steering can also coexist, and the L and R ports of the steering gear are connected to the L and R ports of the electric control steering pilot valve respectively in parallel, and then connected to the L and R ports of the steering valve.

[0030] When the steering valve is a flow amplification type steering valve, the steering is adopted by the steering wheel, at this time, the steering gear with LS signal port is used in cooperation, the steering wheel is rotated to drive the angle sensor and the steering gear to rotate, the L or R port of the steering gear outputs the left or right steering pilot oil signal to the L or R port of the flow amplification type steering valve, the LS oil signal of the steering gear is transmitted to the flow amplification type steering valve, and the angle sensor electrical signal is output to the electric control pump to control the movement of the valve core of the flow amplification type steering valve, and the valve core displacement sensor is driven to act and output an electrical signal, after the movement of the valve core, the steering pump and the steering oil cylinder are connected, at the same time, the electric control steering pump receives the angle sensor electrical signal of the steering wheel to control the variable displacement, and the steering oil cylinder starts to act, the faster the steering speed of the steering wheel, the greater the displacement of the electric control steering pump, and the faster the steering speed of the whole vehicle. Similarly, the slower the steering speed of the steering wheel, the slower the steering speed of the whole vehicle; when the steering mode is electric control steering handle steering, the electric control steering handle outputs different electrical signals to the electric control steering pilot valve after being rotated to the left or right, the electric control steering pilot valve acts after receiving the electrical signal, the L or R port of the electric control steering pilot valve corresponds to output the pilot oil to the L or R port of the flow amplification type steering valve, at the same time, the LS oil signal of the electric control steering handle is transmitted to the flow amplification type steering valve to control the movement of the valve core of the flow amplification type steering valve, and the valve core displacement sensor is driven to act and output an electrical signal, after the movement of the valve core, the steering pump and the steering oil cylinder are connected, at the same time, the electric control steering pump receives the angle sensor electrical signal of the electric control steering handle to control the variable displacement, and the steering oil cylinder starts to act, the greater the angle of the electric control steering handle, the greater the displacement of the electric control steering pump, and the faster the steering speed of the whole vehicle. Similarly, the smaller the angle of the electric control steering handle, the slower the steering speed of the whole vehicle; the steering wheel steering and the electric control steering handle steering can also coexist, and the L, R and LS ports of the steering gear are connected to the L, R and LS ports of the electric control steering pilot valve in parallel, and then connected to the L, R and LS ports of the flow amplification type steering valve.

[0031] As shown in Figure 2 , the above electric control pump steering system with ordinary steering valve or flow amplification type steering valve, when the steering wheel or electric control steering handle acts, first, the main controller detects the angle sensor signal of the steering wheel or electric control steering handle, when the angle sensor electrical signal of the steering wheel or electric control steering handle is 0, the output flow of the electric control pump is 0 or standby flow, and the whole machine has no steering action or steering stops. When the angle sensor electrical signal of the steering wheel or electric control steering handle is not 0, the main controller detects the current steering angle of the whole machine , when the steering angle satisfies: After the steering gear or electronic steering pilot valve actuates, the steering valve receives LS and L or R hydraulic oil signals and then the main valve spool actuates. Simultaneously, the electronic steering pump receives an electrical signal from the steering wheel or electronic steering handle angle sensor and proportionally outputs flow to the steering valve. The main controller detects the direction and magnitude of the steering valve spool displacement and determines whether the displacement direction d and displacement magnitude Δt are zero. When the signal is zero, the main controller outputs no four-wheel differential auxiliary steering control signal or a stop signal. When the signal is not zero, the main controller calculates and outputs a four-wheel differential auxiliary steering control signal based on the current vehicle speed to assist the hydraulic system steering. At the same time, the main controller continuously monitors the current steering angle of the entire machine. ,when or When the main controller stops outputting the four-wheel differential auxiliary steering control signal, steering continues relying on the hydraulic system and the machine's mass inertia until the steering wheel or handle stops turning, or the controller stops steering based on the limit angle signal from the hinge position angle sensor, or the chassis hits the limit device and stops steering. After the steering wheel or electric steering handle is moved, the overall steering angle is detected. Not here When the steering gear or electronic steering pilot valve actuates, the steering valve receives LS and L or R hydraulic oil signals and then the main valve core actuates. Simultaneously, the electronic steering pump receives an electrical signal from the steering wheel or electronic steering handle angle sensor and proportionally outputs flow to the steering valve. The main controller detects the displacement direction d and displacement magnitude Δt of the steering valve core and determines whether these values ​​are zero. When the signal is zero, the main controller outputs no four-wheel differential assist steering control signal or a stop signal. When the signal is not zero, the next action is determined based on the detected steering system pressure p. When the steering system pressure p is outside the (A-Δp, A) pressure range, the main controller outputs no four-wheel differential assist steering control signal. When A-Δp ≤ p ≤ A, the main controller calculates the four-wheel differential assist steering control signal based on the current vehicle speed and outputs a weakened four-wheel differential assist steering control signal. Afterward, it continues to detect the current steering angle of the entire system. rate of change ,when When the value is not 0, the machine will exhibit a steering action and continue to turn. When the value is 0, the main controller increases the output of the four-wheel differential auxiliary steering control signal until the entire machine can turn and continue to steer.

[0032] Example 3

[0033] Based on the four-wheel independent motor driving articulated vehicle steering control method described in embodiment one and embodiment two, the embodiment provides a four-wheel independent motor driving articulated vehicle steering control device, comprising:

[0034] A data acquisition module is configured to detect the current steering angle, vehicle speed, displacement direction and size of the valve core of the steering valve of the whole machine in real time.

[0035] An auxiliary steering module is configured to calculate the four-wheel differential auxiliary steering control signal according to the current steering angle, vehicle speed, displacement direction and size of the valve core of the steering valve of the whole machine, and output the four-wheel differential auxiliary steering control signal according to the set control strategy, so as to assist the hydraulic system steering, thereby improving the unstable shaking of the whole machine during steering start and steering stop, reducing the impact during steering stop, reducing the steering energy consumption, and keeping the hydraulic steering and differential auxiliary steering synchronous.

[0036] Embodiment four

[0037] Based on the four-wheel independent motor driving articulated vehicle steering control device described in embodiment three, the embodiment provides a four-wheel independent motor driving articulated vehicle, which is configured with the four-wheel independent motor driving articulated vehicle steering control device described in embodiment three.

[0038] The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the technical principles of the present application, a number of improvements and modifications can be made, and these improvements and modifications should be considered as the protection scope of the present application.

Claims

1. A steering control method for a four-wheel independent motor driven articulated vehicle, characterized in that, include: Real-time detection of the machine's current steering angle, vehicle speed, and the direction and magnitude of the steering valve core displacement; Based on the current steering angle, vehicle speed, and valve core displacement direction and magnitude of the steering valve, the four-wheel differential auxiliary steering control signal is calculated and output according to the set control strategy to assist the hydraulic system steering, thereby improving the unstable shaking of the whole machine when steering starts and stops, reducing the impact when steering stops, reducing steering energy consumption, and keeping the hydraulic steering and differential auxiliary steering synchronized. The vehicle uses a load-sensitive pump steering system, with steering via a steering wheel and / or an electronically controlled steering handle, and the steering valve is either a standard steering valve or a flow amplification valve. The four-wheel differential control signal is output according to the set control strategy, including: When the steering wheel or electric steering lever is moved, the main controller detects the current steering angle of the entire machine. When the steering angle satisfy: Simultaneously, the steering valve spool actuates, and the main controller detects whether the displacement direction d and displacement magnitude Δt of the steering valve spool are zero. When the signal is zero, the main controller outputs no four-wheel differential auxiliary steering control signal or a stop signal. When the signal is not zero, the main controller calculates and outputs a four-wheel differential auxiliary steering control signal based on the current vehicle speed to assist the hydraulic system in steering. At the same time, the main controller continuously monitors the current steering angle of the entire machine. ,when or When the main controller stops outputting the four-wheel differential auxiliary steering control signal, the steering continues to be carried out by relying on the steering hydraulic system and the inertia of the whole machine until the steering wheel or electric steering handle stops steering, or the main controller stops steering when it detects the limit angle signal of the articulation position angle sensor, or the frame hits the limit device and stops steering. in, This represents a set angle value. This indicates the vehicle's maximum left and right turning angles. This indicates another set angle value.

2. The steering control method for a four-wheel independent motor driven articulated vehicle according to claim 1, characterized in that, According to the set control strategy, the four-wheel differential control signal is output, which also includes: When steering angle Not here When the steering valve core displacement direction d and displacement magnitude Δt are within the specified range, the main controller detects the displacement direction d and displacement magnitude Δt of the steering valve core and determines whether the displacement direction d and displacement magnitude Δt are 0. When the signal is 0, the main controller outputs no four-wheel differential auxiliary steering control signal or a stop signal. When the signal is not 0, the next action is determined based on the detected steering system pressure p. When the steering system pressure p is not within the pressure range of (A-Δp, A), the main controller outputs no four-wheel differential auxiliary steering control signal. When A-Δp≤p≤A, the main controller calculates and outputs the four-wheel differential auxiliary steering control signal based on the current vehicle speed and then continues to detect the current steering angle of the entire machine. rate of change ,when When the value is not 0, the machine will exhibit a steering action and continue to turn. When the value is 0, the main controller outputs a four-wheel differential auxiliary steering control signal until the entire machine begins to steer; Where A represents the high-pressure overflow pressure set by the steering system, and Δp represents a set pressure difference value.

3. The steering control method for a four-wheel independent motor driven articulated vehicle according to claim 1, characterized in that, The vehicle uses an electronically controlled pump steering system, with steering via a steering wheel and / or an electronically controlled steering handle, and the steering valve is either a standard steering valve or a flow amplification valve.

4. The steering control method for a four-wheel independent motor driven articulated vehicle according to claim 3, characterized in that, The four-wheel differential control signal is output according to the set control strategy, including: The main controller detects the angle sensor signal of the steering wheel or electric steering handle. When the electrical signal of the angle sensor of the steering wheel or electric steering handle is 0, the output flow of the electric pump is 0 or maintains a standby flow, and the whole machine has no steering action or the steering stops.

5. The steering control method for a four-wheel independent motor driven articulated vehicle according to claim 4, characterized in that, According to the set control strategy, the four-wheel differential control signal is output, which also includes: When the electrical signal from the angle sensor of the steering wheel or electronic steering handle is not zero, the main controller detects the current steering angle of the entire machine. When the steering angle satisfy: Simultaneously, the steering valve spool actuates, and the main controller detects whether the displacement direction d and displacement magnitude Δt of the steering valve spool are zero. When the signal is zero, the main controller outputs no four-wheel differential auxiliary steering control signal or a stop signal. When the signal is not zero, the main controller calculates and outputs a four-wheel differential auxiliary steering control signal based on the current vehicle speed to assist the hydraulic system in steering. At the same time, the main controller continuously monitors the current steering angle of the entire machine. ,when or When the main controller stops outputting the four-wheel differential auxiliary steering control signal, the steering continues to be carried out by relying on the steering hydraulic system and the inertia of the whole machine until the steering wheel or electric steering handle stops steering, or the main controller stops steering when it detects the limit angle signal of the articulation position angle sensor, or the frame hits the limit device and stops steering. in, This represents a set angle value. This indicates the vehicle's maximum left and right turning angles. This indicates another set angle value.

6. The steering control method for a four-wheel independent motor driven articulated vehicle according to claim 5, characterized in that, According to the set control strategy, the four-wheel differential control signal is output, which also includes: When steering angle Not here When the steering valve core displacement direction d and displacement magnitude Δt are within the specified range, the main controller detects the displacement direction d and displacement magnitude Δt of the steering valve core and determines whether the displacement direction d and displacement magnitude Δt are 0. When the signal is 0, the main controller outputs no four-wheel differential auxiliary steering control signal or a stop signal. When the signal is not 0, the next action is determined based on the detected steering system pressure p. When the steering system pressure p is not within the pressure range of (A-Δp, A), the main controller outputs no four-wheel differential auxiliary steering control signal. When A-Δp≤p≤A, the main controller calculates and outputs the four-wheel differential auxiliary steering control signal based on the current vehicle speed and then continues to detect the current steering angle of the entire machine. rate of change ,when When the value is not 0, the machine will exhibit a steering action and continue to turn. When the value is 0, the main controller outputs a four-wheel differential auxiliary steering control signal until the entire machine begins to steer; Where A represents the high-pressure overflow pressure set by the steering system, and Δp represents a set pressure difference value.

7. A four-wheel independent motor driven articulated vehicle steering control device, characterized in that, include: The data acquisition module is used to detect the current steering angle, vehicle speed, and valve core displacement direction and magnitude of the steering valve in real time. The auxiliary steering module is used to calculate the four-wheel differential auxiliary steering control signal based on the current steering angle of the whole machine, vehicle speed, and the direction and magnitude of the valve core displacement of the steering valve. It then outputs the four-wheel differential auxiliary steering control signal according to the set control strategy to assist the hydraulic system steering, thereby improving the unstable shaking of the whole machine when steering starts and stops, reducing the impact when steering stops, reducing steering energy consumption, and keeping the hydraulic steering and differential auxiliary steering synchronized. The vehicle uses a load-sensitive pump steering system, with steering via a steering wheel and / or an electronically controlled steering handle, and the steering valve is either a standard steering valve or a flow amplification valve. The four-wheel differential control signal is output according to the set control strategy, including: When the steering wheel or electric steering lever is moved, the main controller detects the current steering angle of the entire machine. When the steering angle satisfy: Simultaneously, the steering valve spool actuates, and the main controller detects whether the displacement direction d and displacement magnitude Δt of the steering valve spool are zero. When the signal is zero, the main controller outputs no four-wheel differential auxiliary steering control signal or a stop signal. When the signal is not zero, the main controller calculates and outputs a four-wheel differential auxiliary steering control signal based on the current vehicle speed to assist the hydraulic system in steering. At the same time, the main controller continuously monitors the current steering angle of the entire machine. ,when or When the main controller stops outputting the four-wheel differential auxiliary steering control signal, the steering continues to be carried out by relying on the steering hydraulic system and the inertia of the whole machine until the steering wheel or electric steering handle stops steering, or the main controller stops steering when it detects the limit angle signal of the articulation position angle sensor, or the frame hits the limit device and stops steering. in, This represents a set angle value. This indicates the vehicle's maximum left and right turning angles. This indicates another set angle value.

8. A four-wheel independent motor driven articulated vehicle, characterized in that, The vehicle is equipped with the four-wheel independent motor driven articulated vehicle steering control device as described in claim 7.

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