CN113895511B - Electro-hydraulic integrated steering system and multi-parameter coupling optimization method thereof - Google Patents
Electro-hydraulic integrated steering system and multi-parameter coupling optimization method thereof Download PDFInfo
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
- B62D5/0457—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear characterised by control features of the drive means as such
- B62D5/046—Controlling the motor
- B62D5/0463—Controlling the motor calculating assisting torque from the motor based on driver input
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D3/00—Steering gears
- B62D3/02—Steering gears mechanical
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
- B62D5/061—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle provided with effort, steering lock, or end-of-stroke limiters
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D6/00—Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/40—Engine management systems
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Abstract
The invention discloses an electro-hydraulic integrated steering system and a multi-parameter coupling optimization method thereof, wherein the electro-hydraulic integrated steering system comprises a mechanical transmission module, an electric power-assisted module, a hydraulic power-assisted module and a control module. In addition, the system also has the advantages that multiple actuating mechanisms are mutually redundant, the planet gear speed reducer eliminates the hidden danger of system jamming and keeps the low failure rate of the mechanical rotary valve structure, and the like, and the system is optimized through multi-parameter coupling, so that the cost, the reliability and the road feel can be guaranteed, and the economical efficiency of the system can be maximized.
Description
Technical Field
The invention relates to the technical field of vehicle steering, in particular to an electro-hydraulic integrated steering system and a multi-parameter coupling optimization method thereof.
Background
At present, the research and development progress of automobile electromotion is promoted by each large automobile enterprise, and the existing electric automobile technology is gradually improved due to small volume and light weight of a passenger automobile. However, for commercial vehicles and special vehicles, the vehicle has the characteristics of large volume, large mass and the like, is limited by the power level limitation of the battery and the motor at present, and is difficult to realize the electric operation of the whole vehicle, particularly, a steering system which is one of the core chassis components is limited by the fact that the electric operation cannot be realized due to the overlarge load of the front axle of the vehicle, and the energy consumption problem caused by the electric operation is difficult to follow the national strategic development requirement of the commercial vehicles and the special vehicles.
In view of the success of the hybrid power technology, a set of electric power steering system is added to the original hydraulic power steering system, and the electric power steering system and the hydraulic power steering system are coordinated to realize partial electric driving of the steering systems of commercial vehicles and special vehicles, and the energy-saving advantage of the electric power steering system is utilized to reduce the steering energy consumption of the existing vehicles.
The design scheme of the current electro-hydraulic combined steering system mainly comprises the following steps: for example, chinese patent publication No. CN111055917A, published japanese 2020.04.24, entitled "an electro-hydraulic coupling intelligent steering system and mode switching control method", which discloses a structure in which an electric power steering mechanism is additionally installed on a steering column and an original hydraulic power steering mechanism is retained, but in this scheme, on one hand, because an electric power-assisted mechanism is additionally installed on the steering column, steering feedback from a road surface is isolated, a driver has poor road feel, and two systems have low space utilization in a dispersed layout, and on the other hand, a worm gear reducer of an existing electric power-assisted part also has a problem of power failure or fault self-locking, and once the additionally installed electric power-assisted mechanism fails, the system has a serious consequence of incapability of steering; the chinese patent publication No. CN113212543A, entitled "a variable transmission ratio recirculating ball type electro-hydraulic steering system and control method thereof", discloses a structure in which an electric power-assisted mechanism is installed at the lower end of an original hydraulic steering gear, and a rotary valve therein is replaced by an electromagnetic valve, but this scheme, on one hand, adopts the electromagnetic valve to control, requires a plurality of electromagnetic valve assemblies with complicated structure and high cost, and the reliability problem is difficult to ignore, and on the other hand, the installation position of the electric power-assisted mechanism can ensure good road feel and high space utilization, but still has the problem of power failure or dead locking of a fault system.
In summary, although research on the electro-hydraulic hybrid steering system has been advanced to some extent, the overall scheme is not optimal, and further design optimization is needed to achieve partial electric energy saving and more integration of the system, and meanwhile, the problems of cost, reliability and safety are not brought. In addition, considering that the electro-hydraulic combined steering system has two independent mechanisms, a certain coupling relation exists between the energy management strategy and the structural assembly parameters, and the existing structural optimization method only optimizes the system structure without considering the coupling relation, so that the energy-saving performance of the system is difficult to maximize. Therefore, parameters in the adopted energy management strategy are necessarily considered when the system optimization is carried out, and multi-parameter coupling optimization is carried out so as to realize the optimal matching between the energy management strategy and the parameters of the structural assembly, ensure the necessary requirements of the system and maximize the energy-saving effect of the system.
Disclosure of Invention
The invention aims to solve the technical problem of the background technology, and provides an electro-hydraulic integrated steering system and a multi-parameter coupling optimization method thereof, so as to solve the problems that the design scheme of the electro-hydraulic combined type steering system in the prior art is difficult to achieve electric energy conservation, structural integration, safety, reliability, high cost and structure independent optimization. The invention adopts the design scheme that the electric power-assisted mechanism is integrated at the bottom of the original hydraulic system steering gear, the planetary gear reducer replaces the original worm gear reducer and the mechanical rotary valve structure in the original hydraulic power-assisted mechanism is reserved, on one hand, the electric power-assisted mechanism and the hydraulic power-assisted mechanism are highly integrated, the energy consumption can be reduced through coordination work, on the other hand, the road information can be fed back in real time, and the road feeling is clear for a driver. In addition, the system also has the advantages that multiple actuating mechanisms are mutually redundant, the planet gear speed reducer eliminates the hidden danger of system jamming and keeps the low failure rate of the mechanical rotary valve structure, and the like, and the system is optimized through multi-parameter coupling, so that the cost, the reliability and the road feel can be guaranteed, and the economical efficiency of the system can be maximized.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
an electro-hydraulic integrated steering system of the present invention includes: the device comprises a mechanical transmission module, an electric power-assisted module, a hydraulic power-assisted module and a control module;
the mechanical transmission module comprises: the steering wheel, the steering shaft, the universal joint, the recirculating ball steering gear, the steering rocker arm, the steering drag link, the steering knuckle arm, the left steering knuckle, the left trapezoidal arm, the steering tie rod, the right trapezoidal arm, the right steering knuckle, the left wheel and the right wheel;
the upper end of the steering shaft is connected with the steering wheel, and the lower end of the steering shaft is connected with the upper input end of the recirculating ball steering gear through the universal joint;
the input end of the steering rocker arm is connected with the output end of the recirculating ball steering gear, and the output end of the steering rocker arm is connected with the steering knuckle arm through the steering drag link;
the left steering knuckle is connected with the left wheel, and the steering knuckle arm and the left trapezoid arm are fixed on the left steering knuckle;
two ends of the steering tie rod are respectively connected with the left trapezoidal arm and the right trapezoidal arm;
the right steering knuckle is connected with the right wheel, and the right trapezoidal arm is fixed on the right steering knuckle;
the electric power assisting module comprises: the power assisting motor, the planetary gear reducer and the electromagnetic brake block;
the planetary gear reducer comprises a sun gear, a planet carrier and a gear ring;
the input end of the sun gear is fixedly connected with the output end of the power-assisted motor, and the output end of the sun gear is meshed with the planet gear;
the outer ring of the gear presses against the electromagnetic brake block and is in a pressing braking state when not electrified, and the inner ring of the gear is meshed with the planet gear;
the input end of the planet carrier is fixedly connected with the planet wheel, and the output end of the planet carrier is fixedly connected with the lower input end of the recirculating ball steering gear;
the hydraulic power assisting module comprises: the hydraulic control system comprises a power cylinder, a bearing, a steering screw, a steering nut, a sector, a circulating ball guide pipe, a steering valve, an unloading valve, a one-way valve, a pressure limiting valve, an oil can, a hydraulic pipeline, a gear pump and a hydraulic motor;
the power cylinder is an inner cavity of the recirculating ball steering gear;
the bearing is positioned in the power cylinder and sleeved at the upper end and the lower end of the steering screw rod;
the upper and lower input ends of the steering screw are the upper and lower input ends of the recirculating ball steering gear, and the output end of the steering screw is meshed with the steering nut through the recirculating ball;
the circulating ball guide pipe is arranged on the steering nut and is used as a circulating flow channel of the circulating ball;
the input end of the sector gear is meshed with the rack machined on the steering nut, and the output end of the sector gear is connected with the steering rocker arm;
the unloading valve is arranged in the steering nut and is used for balancing the pressure on two sides of the steering nut when the steering nut moves to the limit position;
the input end of the gear pump is connected with the output end of the hydraulic motor, the oil inlet of the gear pump is connected with the oil can through a hydraulic pipeline, and the oil outlet of the gear pump is connected with the steering valve;
an oil return port of the oil can is connected with the steering valve through a hydraulic pipeline, and an oil outlet of the oil can is connected with the gear pump through a hydraulic pipeline;
the pressure limiting valve and the one-way valve are arranged between a hydraulic pipeline for connecting an oil outlet of the gear pump with the steering valve and a hydraulic pipeline for connecting the steering valve with an oil return port of the oil can, the pressure limiting valve is used for limiting the pressure of hydraulic oil in the hydraulic pipeline, and the one-way valve is used for preventing the hydraulic pipeline from being vacuumized;
the control module includes: the device comprises an electronic control unit, a steering wheel angle sensor, a torque sensor and a vehicle speed sensor;
the input end of the electronic control unit is electrically connected with the steering wheel angle sensor, the torque sensor and the vehicle speed sensor, the output end of the electronic control unit is electrically connected with the power-assisted motor and the hydraulic motor, and power-assisted control is performed according to vehicle state-changing parameters obtained from the sensors during steering;
the steering wheel angle sensor is mounted on a steering wheel and used for obtaining a steering wheel angle signal when a vehicle turns and transmitting the steering wheel angle signal to the electronic control unit.
The torque sensor is arranged on the steering shaft and used for acquiring a torque signal and transmitting the torque signal to the electronic control unit;
the vehicle speed sensor is mounted on a vehicle and used for transmitting an obtained vehicle speed signal to the electronic control unit;
in addition, the invention also provides a multi-parameter coupling optimization method of the electro-hydraulic integrated steering system, which comprises the following steps based on the system:
(1) establishing a mathematical model of the electro-hydraulic integrated steering system;
(2) establishing a steering system optimization target according to the system model established in the step (1);
(3) selecting an energy management strategy to be applied in a system, preselecting 15 energy management strategies which possibly influence the system performance and 15 steering system parameters, respectively testing the parameters by taking three levels, namely maximum variation, minimum variation and intermediate value to obtain test data, analyzing the sensitivity of each parameter, and selecting corresponding design variables;
(4) determining the design variables selected in the step (3) and the constraint conditions corresponding to the parameters, and establishing an optimization model according to the system model in the step (1) and the optimization target in the step (2);
(5) solving optimal structure and energy management strategy parameters by adopting an optimization algorithm based on the optimization model established in the step (4);
further, the mathematical model building step of the electro-hydraulic integrated steering system in the step (1) is as follows:
(1.1) mechanical transmission part model
a) Steering wheel and steering shaft model:
considering the moment of inertia and viscous damping of the steering wheel to neglect the rigidity, neglecting coulomb friction force, the mathematical model is as follows:
T s ＝K s (θ w -θ s ) (2)
in the formula, J w Is the moment of inertia of the steering wheel; b w Is the damping coefficient of the steering wheel; k is s Is the torsion bar stiffness in the torque sensor; theta.theta. w Is a steering wheel corner; theta s Is the steering shaft angle; t is w Inputting torque T to steering wheel s Torque is output for the torque sensor.
b) Recirculating ball diverter model:
in the formula, J g Is the equivalent moment of inertia of the steering screw and the electric power-assisted module speed reducing mechanism, B g Is the equivalent viscous damping coefficient, K, of the steering screw and the reduction mechanism w For steering shaft stiffness, θ g Is the angle of rotation, η, of the steering screw g Is the steering screw feed efficiency, d g For the lead of the steering screw, T EPS For assisting the electric power-assisted module with torque, T p Is the equivalent torque of the steering resistance torque on the sector, r p Is the pitch radius of the sector, F HPS Assistance provided for a hydraulic assistance module, d r The random disturbance torque is equivalent to the road surface random disturbance torque on the steering screw rod.
The hydraulic module boost is expressed as:
F HPS ＝A p (P A -P B ) (4)
in the formula, A p Is the effective area of the piston of the hydraulic cylinder, P A 、P B Respectively representing the pressure across the hydraulic cylinder.
(1.2) Hydraulic Power Module model
a) Gear pump model
Gear pump input torque:
T hm ＝qP s (5)
wherein q is the average displacement of the gear pump, P s For gear pump working pressure, T hm Torque is input to the gear pump.
The pressure at which the gear pump operates is expressed as:
P s ＝2πηT hm /q (6)
wherein pi is a circumferential rate constant, and eta is the mechanical efficiency of the hydraulic pump.
The average displacement of the gear pump when operating is expressed as:
q＝ζ2πm 2 Zb (7)
wherein, zeta is compensation coefficient, m is gear module of the gear pump, Z is gear tooth number of the gear pump, b is gear width of the gear,
the output flow during operation of the gear pump is expressed as:
Q＝qnη V ＝2πkm 2 Zbnη V (8)
wherein n is the gear pump rotation speed, eta V For volumetric efficiency of the gear pump, Q is the gear pump output flow.
b) Hydraulic motor model
The mathematical model of the electrical characteristics of the hydraulic motor is as follows:
in the formula, P h For hydraulic motor power, u h For the armature voltage of the hydraulic motor, i h For armature current of hydraulic motors, R h Is the armature resistance of the hydraulic motor, L h Is armature inductance, θ h For hydraulic motorCorner, K h Is the back electromotive force constant.
The mechanical characteristic mathematical model of the hydraulic motor is as follows:
in the formula, J h Is the moment of inertia of the hydraulic motor, theta h Is a hydraulic motor corner, B h Is the damping coefficient, T, of the hydraulic motor shaft h For electromagnetic torque of hydraulic motors, T hm And outputting torque for the hydraulic motor.
The electromagnetic torque equation of the hydraulic motor is as follows:
T h ＝K hi i h (11)
in the formula, K hi Is the torque coefficient of the hydraulic motor.
c) Steering valve model
The steering valve model is represented as:
in the formula, Q V Is the total inlet flow of the valve body, Q L1 、Q L2 Respectively the oil inlet and outlet flow of the power oil cylinder.
The relationship between the hydraulic oil flow and the pressure difference of each valve port of the steering valve is expressed as follows:
in the formula, Q i (i-1, 2,3,4) is the flow rate through the valve port i, C d Is the flow coefficient, Δ P i The pressure difference between the two sides of the ith valve port, rho is the density of hydraulic oil, A i The valve design is generally symmetrical for the restriction area of the ith port, i.e. A 1 ＝A 3 ，A 2 ＝A 4 。
The opening area of each valve port of the steering valve is expressed as:
in the formula, theta g -θ l Indicating the relative angle of rotation, theta, produced between the steering screw and the steering valve l Is the turning angle of the steering valve, R is the matching radius of the steering valve and the steering screw rod, W 1 Width of the slit of the diverter valve, W 2 The pre-opening gap width, L, of the steering valve port at the middle position 1 Is the axial length of the incision, L 2 Is the axial length of the steering valve port.
(1.3) electric power-assisted module model
The power-assisted motor electrical characteristic mathematical model is as follows:
in the formula, P e To boost the motor power, u e To assist the armature voltage of the motor, i e To assist motor armature current, R e Armature resistance, L, for a booster motor e Is armature inductance, θ e For the angle of rotation of the booster motor, K e Is the back electromotive force constant.
The mechanical characteristic mathematical model of the power-assisted motor is as follows:
in the formula, J e To assist the moment of inertia of the motor, theta e Is a rotation angle of the power-assisted motor, B e For the shaft damping coefficient, T, of the power-assisted motor e For assisting electromagnetic torque of dynamo-electric machines, T em And outputting torque for the power-assisted motor.
The electromagnetic torque equation of the power-assisted motor is as follows:
T e ＝K ei i e (17)
in the formula, K ei Is the torque coefficient of the booster motor.
Electric power-assisted moduleProvided assistance T EPS The expression is as follows:
T EPS ＝T em G star (18)
in the formula, G star Is the reduction ratio of the planetary gear reducer.
Further, the optimization goal in step (2) is:
(2.1) steering road feel optimization target f 1 ：
Where ω is the system frequency, ω 0 40Hz, j is an imaginary unit, X 1 、Y 1 、Z 1 Equivalent moment of inertia, damping and stiffness coefficients, respectively.
(2.2) steering sensitivity optimization target f 2 ：
In the formula, A i (i-0, 1,2,3) is the transfer function molecular coefficient, Q i (i ═ 0,1,2,3,4,5) is the transfer function denominator coefficient.
(2.3) steering energy consumption optimization target f 3 ：
In the formula, T n Torque required for steering, n e For assisting the rotation speed of the motor
(2.4) system cost optimization objective:
f 4 ＝C(P e ,P h ,G star ,d g ,d,r p ) (22)
further, the sensitivity analysis step in the step (3) is as follows:
(3.1) performing range analysis on the steering road feel targets by using the 15 parameters respectively to obtain the sequence of the sensitivity of the eight selected system parameters to the steering road feel targets, and determining corresponding design variable parameters;
(3.2) respectively carrying out range analysis on the steering sensitivity targets by using 15 system parameters to obtain the sequence of the sensitivity of the eight selected system parameters to the steering sensitivity targets, and determining corresponding design variable parameters;
(3.3) performing range analysis on the steering energy consumption targets by using 15 system parameters respectively to obtain the sequence of the sensitivity of the eight selected system parameters to the steering energy consumption targets, and determining corresponding design variable parameters;
(3.4) respectively carrying out range analysis on the system cost target by using the 15 system parameters to obtain the sequence of the sensitivity of the eight selected system parameters to the system cost target, and determining corresponding design variable parameters;
further, the energy management strategy selected in the step (3) is an energy management strategy based on a fuzzy rule, and the final design variable is a membership function node O of the output torque of the electric power assisting module in the fuzzy rule e Membership function node O of hydraulic power assisting module h Membership function node O of the required torque n Hydraulic motor power P h Power P of booster motor e Planetary gear reduction ratio G star Steering screw lead d g Pitch radius r of sector p Gear pump diameter d;
further, the optimization model established in the step (4) is as follows:
in the formula (f) 1 (X) as a steering road feel optimization target, f 2 (X) optimization target for steering sensitivity index, f 3 (X) as steering energy consumption optimization goal, f 4 (X) is a system cost optimization objective.
Further, the optimization method used in the step (5) selects a multi-objective particle swarm optimization algorithm, and specifically comprises the following steps:
(5.1) initializing the particle population m and randomly generating an initial position X 0 And an initial velocity V 0 Initial individual optimal position P of the particle best ＝X 0 ：
External file N s If the number of iterations is null, the number of iterations is set to M, and the position and velocity vector of the ith particle in the iteration process is represented as:
in the formula, P bestK (K ═ X) is the optimum position component for the design variable, X iK (K ═ X) is the position component, V, corresponding to each design variable iK And (K ═ X) is a velocity component corresponding to each design variable.
(5.2) calculating an objective function of each particle, and storing the non-dominated solution into an external file;
(5.3) calculating the distance of each individual in the external file from the center X of the particle center Euclidean distance of (c):
d ij ＝||X i -X center || (26)
according to the roulette selection method, individuals in an external profile are randomly selected as historical global optimum positions G for the particles best ：
(5.4) updating the position X and velocity V of the particle according to equation (27) while updating the P of the particle best And updating the external file N by using the non-dominated solution in the current particle swarm s ：
In the formula, c 1 And c 2 Is a learning factor, r 1 And r 2 To be a random number with a value between 0 and 1, Δ t is the time interval.
(5.5) judging whether the number of individuals in the external file exceeds the given maximum capacity, if so, deleting the individual with the minimum distance from the center, and if not, carrying out the next step;
(5.6) randomly selecting a part of individuals from an external archive to carry out chaotic variation and searching for a non-dominated solution of a nearby area;
(5.7) if the end condition is met, stopping searching, and outputting the Pareto optimal solution set from the external archive, otherwise, repeating the step (5.3) until the Pareto optimal solution set is output;
(5.8) setting priority weight w of each objective function 1 、w 2 、w 3 、w 4 And selecting a final optimization result from the Pareto solution set solved in the step (5.7) according to the target weight.
Compared with the prior art, the invention adopting the technical scheme has the following beneficial effects:
1. the invention adopts the structural schemes of integrating the electric power-assisted mechanism at the bottom of the original hydraulic system steering gear, adopting the planetary gear reducer to replace the original worm gear reducer, retaining the mechanical rotary valve structure in the original hydraulic power-assisted mechanism and the like, thereby not only realizing the high integration of the steering system power-assisted mechanism, but also eliminating the road feel isolation problem under the scheme of adding a tubular column, providing good road feel for drivers, simultaneously, the system can electrify and disconnect the electromagnetic brake block to limit the gear under the fault of the electric power-assisted mechanism, and add a degree of freedom in the reducer, realizing the fault follow-up of the electric power-assisted part and eliminating the hidden trouble of system jamming.
2. The system provided by the invention can further improve the reliability of the steering system by mutually redundant multiple actuating mechanisms and reserving a mechanical rotary valve structure.
3. The invention can improve the system performance without increasing the total cost of the system by optimizing the structure and the power of the system, and has the advantages of great technical advantage and high feasibility.
4. The multi-parameter coupling optimization method provided by the invention can realize the common optimization of the structure assembly parameters and the energy management strategy, so that the energy management strategy and the structure assembly parameters are matched with each other, and the economy of the system is maximized.
Drawings
FIG. 1 is a schematic view of an electro-hydraulic integrated steering system of the present invention;
FIG. 2 is a schematic view of a planetary gear reducer of the present invention;
FIG. 3 is a flow chart of a method for optimizing the configuration of an electro-hydraulic integrated steering system of the present invention;
FIG. 4 is a flow chart of an optimization algorithm of the present invention;
in the figure, 1-steering wheel, 2-steering wheel angle sensor, 3-torque sensor, 4-steering shaft, 5-universal joint, 6-bearing, 7-sector, 8-steering rocker arm, 9-steering drag link, 10-left wheel, 11-left steering knuckle, 12-left trapezoidal arm, 13-steering knuckle arm, 14-steering tie rod, 15-electromagnetic brake block, 16-steering valve, 17-power motor, 18-planetary gear reducer, 19-circulating ball, 20-unloading valve, 21-electronic control unit, 22-gear pump, 23-vehicle speed sensor, 24-right trapezoidal arm, 25-right steering knuckle, 26-right wheel, 27-hydraulic motor, 28-circulating ball conduit, 29-steering nut, 30-one-way valve, 31-hydraulic pipeline, 32-pressure limiting valve, 33-oilcan, 34-power cylinder, 35-circulating ball steering gear, 36-steering screw, 37-gear ring, 38-sun gear, 39-planet gear and 40-planet carrier.
Detailed Description
The technical scheme of the invention is further explained in detail by combining the attached drawings:
the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
Specific implementation 1:
the method for establishing the mathematical model of the electro-hydraulic integrated steering system comprises the following steps:
(1.1) mechanical transmission part model
a. Steering wheel and steering shaft model:
considering the moment of inertia and viscous damping of the steering wheel to neglect the rigidity, neglecting coulomb friction force, the mathematical model is as follows:
T s ＝K s (θ w -θ s ) (2)
in the formula, J w Is the moment of inertia of the steering wheel; b is w Is the damping coefficient of the steering wheel; k s Is the torsion bar stiffness in the torque sensor; theta w Is a steering wheel corner; theta s Is the steering shaft angle; t is w Inputting torque T to steering wheel s Torque is output for the torque sensor.
b. Recirculating ball redirector model:
in the formula, J g Is the equivalent moment of inertia of the steering screw and the electric power-assisted module speed reducing mechanism, B g Is the equivalent viscous damping coefficient, K, of the steering screw and the reduction mechanism w For steering shaft stiffness, θ g Is the angle of rotation, η, of the steering screw g Is the steering screw feed efficiency, d g For the lead of the steering screw, T EPS For assisting the electric power-assisted module with torque, T p Is the equivalent torque of the steering resistance torque on the sector, r p Is the pitch radius of the sector, F HPS Assistance provided for a hydraulic assistance module, d r The random disturbance torque is equivalent to the road surface random disturbance torque on the steering screw rod.
The hydraulic module boost is expressed as:
F HPS ＝A p (P A -P B ) (4)
in the formula, A p Is the effective area of the piston of the hydraulic cylinder, P A 、P B Respectively representAnd (4) pressure at two ends of the hydraulic cylinder.
(1.2) Hydraulic Power Module model
a. Gear pump model
Gear pump input torque:
T hm ＝qP s (5)
wherein q is the average displacement of the gear pump, P s For gear pump working pressure, T hm Torque is input to the gear pump.
The pressure at which the gear pump operates is expressed as:
P s ＝2πηT hm /q (6)
wherein pi is a circumferential rate constant, and eta is the mechanical efficiency of the hydraulic pump.
The average displacement of the gear pump when operating is expressed as:
q＝ζ2πm 2 Zb (7)
wherein, zeta is compensation coefficient, m is gear module of the gear pump, Z is gear tooth number of the gear pump, b is gear width of the gear,
the output flow during operation of the gear pump is expressed as:
Q＝qnη V ＝2πkm 2 Zbnη V (8)
wherein n is the gear pump rotation speed, eta V For volumetric efficiency of the gear pump, Q is the gear pump output flow.
b. Hydraulic motor model
The mathematical model of the electrical characteristics of the hydraulic motor is as follows:
in the formula, P h For hydraulic motor power, u h For the armature voltage of the hydraulic motor, i h For armature current of hydraulic motors, R h Is the armature resistance of the hydraulic motor, L h Is armature inductance, θ h Is a hydraulic motor corner, K h Is the back electromotive force constant.
The mechanical characteristic mathematical model of the hydraulic motor is as follows:
in the formula, J h Is the moment of inertia of the hydraulic motor, theta h Is a hydraulic motor corner, B h For the damping coefficient of the hydraulic motor shaft, T h For electromagnetic torque of hydraulic motors, T hm And outputting torque for the hydraulic motor.
The electromagnetic torque equation of the hydraulic motor is as follows:
T h ＝K hi i h (11)
in the formula, K hi Is the torque coefficient of the hydraulic motor.
c. Steering valve model
The steering valve model is represented as:
in the formula, Q V Is the total inlet flow of the valve body, Q L1 、Q L2 Respectively the oil inlet and outlet flow of the power oil cylinder.
The relationship between the hydraulic oil flow and the pressure difference of each valve port of the steering valve is expressed as follows:
in the formula, Q i (i-1, 2,3,4) is the flow rate through the valve port i, C d Is the flow coefficient, Δ P i The pressure difference between the two sides of the ith valve port, rho is the density of hydraulic oil, A i For the restriction area of the ith port, the valve structure is generally of symmetrical design, i.e. A 1 ＝A 3 ，A 2 ＝A 4 。
The opening area of each valve port of the steering valve is expressed as:
in the formula, theta g -θ l Indicating the relative angle of rotation, theta, produced between the steering screw and the steering valve l Is the turning angle of the steering valve, R is the matching radius of the steering valve and the steering screw rod, W 1 Width of the slit of the diverter valve, W 2 The pre-opening gap width, L, of the steering valve port at the middle position 1 Is the axial length of the incision, L 2 Is the axial length of the steering valve port.
(1.3) electric power-assisted module model
The power-assisted motor electrical characteristic mathematical model is as follows:
in the formula, P e To boost the motor power, u e To assist the armature voltage of the motor, i e To assist motor armature current, R e Armature resistance, L, for a booster motor e Is armature inductance, θ e For the angle of rotation of the booster motor, K e Is the back electromotive force constant.
The mechanical characteristic mathematical model of the power-assisted motor is as follows:
in the formula, J e To assist the moment of inertia of the motor, theta e For the angle of rotation of the booster motor, B e For the shaft damping coefficient, T, of the power-assisted motor e For assisting electromagnetic torque of dynamo-electric machines, T em And outputting torque for the power-assisted motor.
The electromagnetic torque equation of the power-assisted motor is as follows:
T e ＝K ei i e (17)
in the formula, K ei Is the torque coefficient of the booster motor.
Power-assisted T provided by electric power-assisted module EPS The expression is as follows:
T EPS ＝T em G star (18)
in the formula, G star Is the reduction ratio of the planetary gear reducer.
Specific implementation 2:
the optimization target of the steering system is established as follows:
(2.1) steering road feel optimization target f 1 ：
Where ω is the system frequency, ω 0 40Hz, j is the imaginary unit, X 1 、Y 1 、Z 1 Equivalent moment of inertia, damping and stiffness coefficients, respectively.
(2.2) steering sensitivity optimization target f 2 ：
In the formula, A i (i-0, 1,2,3) is the transfer function molecular coefficient, Q i (i ═ 0,1,2,3,4,5) is the transfer function denominator coefficient.
(2.3) steering energy consumption optimization target f 3 ：
In the formula, T n Torque required for steering, n e For assisting the rotation speed of the motor
(2.4) system cost optimization objective:
f 4 ＝C(P e ,P h ,G star ,d g ,d,r p ) (22)
specific implementation 3:
the optimization method selects a multi-objective particle swarm optimization algorithm, and comprises the following specific steps:
(3.1) initializing the particle population m and randomly generating an initial position X 0 And an initial velocity V 0 Initial population of particlesPreferred position P best ＝X 0 ：
External file N s If the number of iterations is null, the number of iterations is set to M, and the position and velocity vector of the ith particle in the iteration process is represented as:
in the formula, P bestK (K ═ X) is the optimum position component for the design variable, X iK (K ═ X) is a position component, V, corresponding to each design variable iK And (K ═ X) is a velocity component corresponding to each design variable.
(3.2) calculating an objective function of each particle, and storing the non-dominated solution into an external file;
(3.3) calculating the distance of each individual in the external file from the center X of the particle center Euclidean distance of (c):
d ij ＝||X i -X center || (25)
randomly selecting individuals in an external profile as historical global optimum positions G for the particles according to a roulette selection method best ：
(3.4) updating the position X and velocity V of the particle according to equation (26) while updating the P of the particle best And updating the external file N by using the non-dominated solution in the current particle swarm s ：
In the formula, c 1 And c 2 Is a learning factor, r 1 And r 2 Is a value between 0 and 1The number of machines, Δ t, is the time interval.
(3.5) judging whether the number of individuals in the external file exceeds the given maximum capacity, if so, deleting the individual with the minimum distance from the center, and if not, carrying out the next step;
(3.6) randomly selecting part of individuals from an external archive to carry out chaotic variation, and searching a non-dominant solution of a nearby area;
(3.7) if the end condition is met, stopping searching, and outputting the Pareto optimal solution set from the external archive, otherwise, repeating the step (3.3) until the Pareto optimal solution set is output;
(3.8) setting priority weight w of each objective function 1 、w 2 、w 3 、w 4 And selecting a final optimization result from the Pareto solution set solved in the step (3.7) according to the target weight.
The above-mentioned embodiments, objects, technical solutions and advantages of the present invention are further described in detail, it should be understood that the above-mentioned embodiments are only illustrative of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. An electro-hydraulic integrated steering system and a multi-parameter coupling optimization method thereof are characterized by specifically comprising the following steps: the device comprises a mechanical transmission module, an electric power-assisted module, a hydraulic power-assisted module and a control module;
the mechanical transmission module comprises: the steering wheel, the steering shaft, the universal joint, the recirculating ball steering gear, the steering rocker arm, the steering drag link, the steering knuckle arm, the left steering knuckle, the left trapezoidal arm, the steering tie rod, the right trapezoidal arm, the right steering knuckle, the left wheel and the right wheel;
the upper end of the steering shaft is connected with the steering wheel, and the lower end of the steering shaft is connected with the upper input end of the recirculating ball steering gear through the universal joint;
the input end of the steering rocker arm is connected with the output end of the recirculating ball steering gear, and the output end of the steering rocker arm is connected with the steering knuckle arm through the steering drag link;
the left steering knuckle is connected with the left wheel, and the steering knuckle arm and the left trapezoid arm are fixed on the left steering knuckle;
two ends of the steering tie rod are respectively connected with the left trapezoidal arm and the right trapezoidal arm;
the right steering knuckle is connected with the right wheel, and the right trapezoidal arm is fixed on the right steering knuckle;
the electric power assisting module comprises: the power assisting motor, the planetary gear reducer and the electromagnetic brake block;
the planetary gear reducer comprises a sun gear, a planet carrier and a gear ring;
the input end of the sun gear is fixedly connected with the output end of the power-assisted motor, and the output end of the sun gear is meshed with the planet gear;
the outer ring of the gear is pressed against the electromagnetic brake block and is in a pressing braking state when not electrified, and the inner ring of the gear is meshed with the planet gear;
the input end of the planet carrier is fixedly connected with the planet wheel, and the output end of the planet carrier is fixedly connected with the lower input end of the recirculating ball steering gear;
the hydraulic power assisting module comprises: the hydraulic control system comprises a power cylinder, a bearing, a steering screw rod, a steering nut, a sector, a circulating ball guide pipe, a steering valve, an unloading valve, a one-way valve, a pressure limiting valve, an oil can, a hydraulic pipeline, a gear pump and a hydraulic motor;
the power cylinder is an inner cavity of the recirculating ball steering gear;
the bearing is positioned in the power cylinder and sleeved at the upper end and the lower end of the steering screw rod;
the upper and lower input ends of the steering screw are the upper and lower input ends of the recirculating ball steering gear, and the output end of the steering screw is meshed with the steering nut through the recirculating ball;
the circulating ball guide pipe is arranged on the steering nut and is used as a circulating flow channel of the circulating ball;
the input end of the sector gear is meshed with the rack machined on the steering nut, and the output end of the sector gear is connected with the steering rocker arm;
the unloading valve is arranged in the steering nut and is used for balancing the pressure on two sides of the steering nut when the steering nut moves to the limit position;
the input end of the gear pump is connected with the output end of the hydraulic motor, the oil inlet of the gear pump is connected with the oil can through a hydraulic pipeline, and the oil outlet of the gear pump is connected with the steering valve;
an oil return port of the oil can is connected with the steering valve through a hydraulic pipeline, and an oil outlet of the oil can is connected with the gear pump through a hydraulic pipeline;
the pressure limiting valve and the one-way valve are arranged between a hydraulic pipeline for connecting an oil outlet of the gear pump and the steering valve and a hydraulic pipeline for connecting the steering valve and an oil return port of the oil can, wherein the pressure limiting valve is used for limiting the pressure of hydraulic oil in the hydraulic pipeline, and the one-way valve is used for preventing the hydraulic pipeline from being vacuumized;
the control module includes: the device comprises an electronic control unit, a steering wheel angle sensor, a torque sensor and a vehicle speed sensor;
the input end of the electronic control unit is electrically connected with the steering wheel angle sensor, the torque sensor and the vehicle speed sensor, the output end of the electronic control unit is electrically connected with the power-assisted motor and the hydraulic motor, and power-assisted control is carried out according to vehicle state-changing parameters obtained from the sensors during steering;
the steering wheel angle sensor is arranged on a steering wheel and used for acquiring a steering wheel angle signal when a vehicle turns and transmitting the steering wheel angle signal to the electronic control unit;
the torque sensor is arranged on the steering shaft and used for acquiring a torque signal and transmitting the torque signal to the electronic control unit;
the vehicle speed sensor is arranged on a vehicle and used for transmitting an obtained vehicle speed signal to the electronic control unit;
in addition, the invention also provides a multi-parameter coupling optimization method of the electro-hydraulic integrated steering system, which comprises the following steps based on the system:
(1) establishing a mathematical model of the electro-hydraulic integrated steering system;
(2) establishing a steering system optimization target according to the system model established in the step (1);
(3) selecting an energy management strategy based on a fuzzy rule as an energy management strategy to be applied in a system, preselecting 15 energy management strategies which may influence the system performance and 15 steering system parameters, respectively testing the parameters by taking three levels of values, namely maximum variation, minimum variation and intermediate value to obtain test data, analyzing the sensitivity of each parameter, and selecting corresponding design variables;
wherein the sensitivity analysis steps of each parameter are as follows:
(3.1) performing range analysis on the steering road feel targets by using the 15 parameters respectively to obtain the sequence of the sensitivity of the eight selected system parameters to the steering road feel targets, and determining corresponding design variable parameters;
(3.2) respectively carrying out range analysis on the steering sensitivity targets by using 15 system parameters to obtain the sequence of the sensitivity of the eight selected system parameters to the steering sensitivity targets, and determining corresponding design variable parameters;
(3.3) performing range analysis on the steering energy consumption targets by using 15 system parameters respectively to obtain the sequence of the sensitivity of the eight selected system parameters to the steering energy consumption targets, and determining corresponding design variable parameters;
(3.4) respectively carrying out range analysis on the system cost target by using the 15 system parameters to obtain the sequence of the sensitivity of the eight selected system parameters to the system cost target, and determining corresponding design variable parameters;
combining the design variables determined in the steps (3.1) - (3.4) to obtain the design variables selected in the step (3), namely a membership function node Oe of the output torque of the electric power-assisted module, a membership function node Oh of the hydraulic power-assisted module, a membership function node On of the required torque, the power Ph of a hydraulic motor, the power Pe of the power-assisted motor, a planetary gear reduction ratio Gstar, a steering screw lead dg, a sector pitch radius rp and a gear pump diameter d in the fuzzy rule;
(4) determining the design variables selected in the step (3) and the constraint conditions corresponding to the parameters, and establishing an optimization model according to the system model in the step (1) and the optimization target in the step (2);
(5) and (5) solving optimal structure and energy management strategy parameters by adopting an optimization algorithm based on the optimization model established in the step (4).
2. The electro-hydraulic integrated steering system and the multi-parameter coupling optimization method thereof according to claim 1, wherein the step (1) of establishing the mathematical model of the electro-hydraulic integrated steering system comprises the following steps:
step (1.1) mechanical transmission part model
a. Steering wheel and steering shaft model:
considering the moment of inertia and viscous damping of the steering wheel to neglect the rigidity, neglecting coulomb friction force, the mathematical model is as follows:
T s ＝K s (θ w -θ s )
in the formula, J w Is the moment of inertia of the steering wheel; b is w Is the damping coefficient of the steering wheel; k is s Is the torsion bar stiffness in the torque sensor; theta w Is a steering wheel corner; theta.theta. s Is the steering shaft angle; t is w Inputting torque T to steering wheel s Outputting torque for the torque sensor;
b. recirculating ball redirector model:
in the formula, J g Is the equivalent moment of inertia of the steering screw and the electric power module speed reducing mechanism, B g Is the equivalent viscous damping coefficient, K, of the steering screw and the reduction mechanism w For steering shaft stiffness, θ g Is the angle of rotation, η, of the steering screw g Is the steering screw feed efficiency, d g For the lead of the steering screw, T EPS For assisting electricallyModule assistance torque, T p Is the equivalent torque of the steering resistance torque on the sector, r p Is the pitch radius of the sector, F HPS Assistance provided for a hydraulic assistance module, d r The torque is equivalent to the road surface random disturbance torque on the steering screw rod;
the hydraulic module boost is expressed as:
F HPS ＝A p (P A -P B )
in the formula, A p Is the effective area of the piston of the hydraulic cylinder, P A 、P B Respectively representing the pressure at two ends of the hydraulic cylinder;
step (1.2) hydraulic power-assisted module model
a. Gear pump model
Gear pump input torque:
T hm ＝qP s
wherein q is the average displacement of the gear pump, P s For gear pump working pressure, T hm Inputting torque for the gear pump;
the pressure at which the gear pump operates is expressed as:
P s ＝2πηT hm /q
wherein pi is a circumferential rate constant, and eta is the mechanical efficiency of the hydraulic pump;
the average displacement of the gear pump when operating is expressed as:
q＝ζ2πm 2 Zb
wherein, zeta is compensation coefficient, m is gear module of the gear pump, Z is gear tooth number of the gear pump, b is gear width of the gear,
the output flow during operation of the gear pump is expressed as:
Q＝qnη V ＝2πkm 2 Zbnη V
wherein n is the gear pump rotation speed, eta V The volumetric efficiency of the gear pump is shown, and Q is the output flow of the gear pump;
b. hydraulic motor model
The mathematical model of the electrical characteristics of the hydraulic motor is as follows:
P h ＝u h i h
in the formula, P h For hydraulic motor power, u h For the armature voltage of the hydraulic motor, i h For armature current of hydraulic motors, R h Is the armature resistance of the hydraulic motor, L h Is armature inductance, θ h Is a hydraulic motor corner, K h Is the back electromotive force constant;
the mechanical characteristic mathematical model of the hydraulic motor is as follows:
in the formula, J h Is the moment of inertia of the hydraulic motor, theta h Is a hydraulic motor corner, B h For the damping coefficient of the hydraulic motor shaft, T h For electromagnetic torque of hydraulic motors, T hm Outputting torque for the hydraulic motor;
the electromagnetic torque equation of the hydraulic motor is as follows:
T h ＝K hi i h
in the formula, K hi Is the torque coefficient of the hydraulic motor;
c. steering valve model
The steering valve model is represented as:
in the formula, Q V Is the total inlet flow of the valve body, Q L1 、Q L2 The flow rates of the inlet oil and the outlet oil of the power oil cylinder are respectively;
the relationship between the hydraulic oil flow and the pressure difference of each valve port of the steering valve is expressed as follows:
in the formula, Q i (i-1, 2,3,4) is the flow rate through the valve port i, C d Is the flow coefficient, Δ P i The pressure difference between the two sides of the ith valve port, rho is the density of hydraulic oil, A i The valve design is generally symmetrical for the restriction area of the ith port, i.e. A 1 ＝A 3 ，A 2 ＝A 4 ；
The opening area of each valve port of the steering valve is expressed as:
in the formula, theta g -θ l Indicating the relative angle of rotation, theta, produced between the steering screw and the steering valve l Is the turning angle of the steering valve, R is the matching radius of the steering valve and the steering screw rod, W 1 Width of the slit of the diverter valve, W 2 The pre-opening gap width, L, of the steering valve port at the middle position 1 Is the axial length of the incision, L 2 The axial length of the steering valve port;
step (1.3) electric power-assisted module model
The power-assisted motor electrical characteristic mathematical model is as follows:
P e ＝u e i e
in the formula, P e To boost the motor power, u e To assist the armature voltage of the motor, i e To assist motor armature current, R e Armature resistance, L, for a booster motor e Is armature inductance, θ e For the angle of rotation of the booster motor, K e Is the back electromotive force constant;
the mechanical characteristic mathematical model of the power-assisted motor is as follows:
in the formula, J e To assist the moment of inertia of the motor, theta e For the angle of rotation of the booster motor, B e Is a shaft damping coefficient, T, of the booster motor e For assisting electromagnetic torque of dynamo-electric machines, T em Outputting torque for the power-assisted motor;
the electromagnetic torque equation of the power-assisted motor is as follows:
T e ＝K ei i e
in the formula, K ei Is the torque coefficient of the booster motor;
power-assisted T provided by electric power-assisted module EPS The expression is as follows:
T EPS ＝T em G star
in the formula, G star Is the reduction ratio of the planetary gear reducer.
3. The electro-hydraulic integrated steering system and the multi-parameter coupling optimization method thereof according to claim 1, wherein the optimization objective in the step (2) is as follows:
step (2.1) turning road feel optimization target f 1:
in the formula, ω is a system frequency, ω 0 is a cut-off frequency of 40Hz, j is an imaginary unit, and X1, Y1 and Z1 are equivalent rotational inertia, damping and stiffness coefficients, respectively;
step (2.2) steering sensitivity optimization target f 2:
where Ai (i ═ 0,1,2,3) is a transfer function numerator coefficient, and Qi (i ═ 0,1,2,3,4,5) is a transfer function denominator coefficient;
step (2.3) turns to energy consumption optimization objective f 3:
in the formula, T n Torque required for steering, n e For assisting the rotation speed of the motor
Step (2.4) system cost optimization objective:
f 4 ＝C(P e ,P h ,G star ,d g ,d,r p ) 。
4. the electro-hydraulic integrated steering system and the multi-parameter coupling optimization method thereof according to claim 1, wherein the optimization model established in the step (4) is as follows:
in the formula (f) 1 (X) as a steering road feel optimization target, f 2 (X) optimization target for steering sensitivity index, f 3 (X) as steering energy consumption optimization goal, f 4 (X) is a system cost optimization objective.
5. The electro-hydraulic integrated steering system and the multi-parameter coupling optimization method thereof according to claim 1, wherein the optimization method used in the step (5) adopts a multi-objective particle swarm optimization algorithm, and the method comprises the following specific steps:
step (5.1) initializes the particle population m, randomly generates an initial position X0 and an initial velocity V0, and the initial individual optimal position Pbest of the particle is X0:
the external file Ns is empty, the number of iterations is set to M, and the position and velocity vector of the ith particle in the iteration process is represented as:
in the formula, PbestK (K ═ X) is an optimum position component corresponding to a design variable, XiK (K ═ X) is a position component corresponding to each design variable, and ViK (K ═ X) is a velocity component corresponding to each design variable;
step (5.2) calculating the objective function of each particle, and storing the non-dominated solution into an external file;
step (5.3) calculating the Euclidean distance from each individual in the external file to the center Xcenter of the particle:
d ij ＝||X i -X center ||
according to the roulette selection method, individuals in an external file are randomly selected as historical global optimum positions Gbest of the particles:
and (5.4) updating the position X and the speed V of the particle by the formula, updating the Pbest of the particle, and updating the external file Ns by using the non-dominated solution in the current particle swarm:
V i (t+1)＝V i (t)+c 1 *r 1 *[P best (t)-X i (t)]+c 2 *r 2 *[G best (t)-X i (t)]
X i (t+1)＝X i (t)+V i (t+1)Δt
in the formula, c1 and c2 are learning factors, r1 and r2 are random numbers with the value between 0 and 1, and delta t is a time interval;
step (5.5) judging whether the number of individuals in the external archive exceeds the given maximum capacity, if so, deleting the individual with the minimum distance from the center, otherwise, carrying out the next step;
step (5.6) randomly selecting part of individuals from external archives to carry out chaotic variation, and searching non-dominated solutions in the nearby area;
if the end condition is met, stopping searching, and outputting the Pareto optimal solution set from the external archive, otherwise, turning to the step (5.3) to recycle until the Pareto optimal solution set is output;
and (5.8) setting priority weights w1, w2, w3 and w4 of each objective function, and selecting a final optimization result from the Pareto solution set solved in the step (5.7) according to the objective weights.
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| CN114802423B (en) * | 2022-04-29 | 2023-04-28 | 吉林大学 | Drive-by-wire turns to road feel analog system with mechanical redundancy |
| CN116620387B (en) * | 2023-06-06 | 2024-01-12 | 南京航空航天大学 | Redundant electrohydraulic composite steering system and fault-tolerant control method thereof |
| CN116923535B (en) * | 2023-09-18 | 2023-11-17 | 南京航空航天大学 | Distributed four-wheel steering system and double steering domain corner coordination method thereof |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20100072906A (en) * | 2008-12-22 | 2010-07-01 | 영신정공 주식회사 | Power steering system with mdps and ehps' parallel |
| CN106800040A (en) * | 2017-02-24 | 2017-06-06 | 南京航空航天大学 | A kind of automobile electrically-controlled composite turning system and its Multipurpose Optimal Method |
| CN107901979A (en) * | 2017-11-10 | 2018-04-13 | 南京双环电器股份有限公司 | A kind of electro-hydraulic active steering road feel control system of automobile and its control method |
| CN109318982A (en) * | 2018-08-02 | 2019-02-12 | 江苏大学 | A kind of hybrid power steering system characteristic parameter matching method |
| CN109614703A (en) * | 2018-12-11 | 2019-04-12 | 南京天航智能装备研究院有限公司 | A kind of multi- disciplinary integrated modeling of the electric-hydraulic combined steering system of automobile and optimization method |
| CN109733466A (en) * | 2018-12-24 | 2019-05-10 | 南京航空航天大学 | A kind of its Multipurpose Optimal Method of electro-hydraulic intelligent steering system of automobile |
| CN109774785A (en) * | 2019-01-02 | 2019-05-21 | 南京航空航天大学 | A kind of pinion and-rack electric hydraulic steering system and optimization method based on magnetorheological fluid |
| CN113212546A (en) * | 2021-05-21 | 2021-08-06 | 南京航空航天大学 | Commercial vehicle electro-hydraulic composite steering system and segmented energy management method thereof |
| CN113335371A (en) * | 2021-06-30 | 2021-09-03 | 南京航空航天大学 | Multifunctional electric circulating ball steering system of commercial vehicle and control method thereof |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102007012392A1 (en) * | 2006-04-08 | 2007-10-11 | Ixetic Bad Homburg Gmbh | Automotive power steering system has first hydraulic motor engaging with rack and pinion mechanism |
| CN106741132B (en) * | 2016-11-15 | 2022-10-21 | 南京航空航天大学 | Controller of multi-mode active steering system and control method thereof |
| CN110949496B (en) * | 2019-11-15 | 2021-06-18 | 江苏大学 | Double-oil-pump type hybrid electric control steering system and control method thereof |
| CN113895511B (en) * | 2021-10-09 | 2022-09-16 | 南京航空航天大学 | Electro-hydraulic integrated steering system and multi-parameter coupling optimization method thereof |
-
2021
- 2021-10-09 CN CN202111176287.XA patent/CN113895511B/en active Active
-
2022
- 2022-05-16 WO PCT/CN2022/092942 patent/WO2023056751A1/en unknown
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20100072906A (en) * | 2008-12-22 | 2010-07-01 | 영신정공 주식회사 | Power steering system with mdps and ehps' parallel |
| CN106800040A (en) * | 2017-02-24 | 2017-06-06 | 南京航空航天大学 | A kind of automobile electrically-controlled composite turning system and its Multipurpose Optimal Method |
| CN107901979A (en) * | 2017-11-10 | 2018-04-13 | 南京双环电器股份有限公司 | A kind of electro-hydraulic active steering road feel control system of automobile and its control method |
| CN109318982A (en) * | 2018-08-02 | 2019-02-12 | 江苏大学 | A kind of hybrid power steering system characteristic parameter matching method |
| CN109614703A (en) * | 2018-12-11 | 2019-04-12 | 南京天航智能装备研究院有限公司 | A kind of multi- disciplinary integrated modeling of the electric-hydraulic combined steering system of automobile and optimization method |
| CN109733466A (en) * | 2018-12-24 | 2019-05-10 | 南京航空航天大学 | A kind of its Multipurpose Optimal Method of electro-hydraulic intelligent steering system of automobile |
| CN109774785A (en) * | 2019-01-02 | 2019-05-21 | 南京航空航天大学 | A kind of pinion and-rack electric hydraulic steering system and optimization method based on magnetorheological fluid |
| CN113212546A (en) * | 2021-05-21 | 2021-08-06 | 南京航空航天大学 | Commercial vehicle electro-hydraulic composite steering system and segmented energy management method thereof |
| CN113335371A (en) * | 2021-06-30 | 2021-09-03 | 南京航空航天大学 | Multifunctional electric circulating ball steering system of commercial vehicle and control method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 朱庆华 ; 闵永军 ; 张涌 ; 赵万忠 ; 陈鹏.A型纯电动客车EHPS助力电机转速控制优化.《森林工程》.2019, * |
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