CN106800040A - A kind of automobile electrically-controlled composite turning system and its Multipurpose Optimal Method - Google Patents

Abstract

The invention discloses a kind of automobile electrically-controlled composite turning system and its Multipurpose Optimal Method, automatically controlled composite turning system includes control module（ECU）, machine driving module, electric-controlled hydraulic power-assisted module and electric boosted module.Machine driving module is including steering wheel, steering column, ball-and-nut steering gear and track rod etc.；Electric-controlled hydraulic power-assisted module is including hydraulic tank, hydraulic pump, hydraulic pump drive motor and rotary valve etc.；Electric boosted module is including arc linear motor etc..The participation method of electro-hydraulic power-assisted in composite turning system is determined according to driver's hobby, road conditions, speed, driver's steering wheel angle and rotating speed etc..And using motor turning road feel, steering sensitivity, turn to energy consumption as optimization aim, using power steering scope as constraints, composite turning system important parameter is optimized by a kind of new Multipurpose Optimal Method, lifts the combination property of composite turning system.

Description

A kind of automobile electrically-controlled composite turning system and its Multipurpose Optimal Method

Technical field

The present invention relates to automobile steering system field, more particularly to a kind of automobile electrically-controlled composite turning system and its multiple target Optimization method.

Background technology

Existing steering uses hydraulic power-assist steering system, Electro-Hydraulic Power Steering System and electric boosted mostly Steering.Traditional hydraulic power-assist steering system, its power steering is provided by engine, and liquid is still driven in the case of non-steering Press pump is worked, and steering situation constitutes about 10% of automobile running working condition or so, therefore certain waste is caused to the energy, and Its assist characteristic is uncontrollable, in automobile low speed, hard steering, and during automobile high-speed, steering sensitivity is too high；Electric-controlled hydraulic power-assisted Steering is controlled according to speed etc. to power-assisted flow, and the size according to required power-assisted controls flow to realize assist characteristic Regulation, but use the Electro-Hydraulic Power Steering System of valve control, its power-assisted is still driven by engine, turns to energy consumption Still higher, using pure motor-driven Electro-Hydraulic Power Steering System, because the limitation of voltage, its power steering is limited； The widely used electric boosting steering system on new-energy automobile, its power steering is provided by motor, and energy consumption is minimum, But the voltage limitation of power supply is constrained to, the power steering provided under existing motor size is relatively small.Automatically controlled composite turning System uses different power-assisted strategies under different steering situations, has had the excellent road of Electro-Hydraulic Power Steering System concurrently Sense, the energy saving of electric boosting steering system is car and lorry in future while compensate for both less defects of power-assisted scope Preferable power-assisted selection.

But in present automatically controlled composite turning systematic research, to the research of its structure also in the starting stage, also permitted More incomplete place is, it is necessary to be improved；Additionally, automatically controlled composite turning system is related to steering response, steering sensitivity, steering The many aspects such as energy consumption, to the operating experience of driver, energy saving tool has a significant impact, and how to improve the maneuverability and warp of automobile The research of Ji property also rarely has open report.

In terms of optimized algorithm, traditional multi-objective optimization algorithm has good optimizing ability, using retaining elite plan Sort method slightly can obtain preferable Pareto disaggregation, but algorithm is easily trapped into part most in itself in the presence of being easy to precocious The problem of excellent solution, and, in optimization process, with optimal solution is approached, optimization efficiency reduction, or even presence cannot finally be found To the problem of optimal solution.

The content of the invention

The technical problems to be solved by the invention are directed to involved defect in background technology, there is provided a kind of automobile electricity Control composite turning system and its Multipurpose Optimal Method.

The present invention uses following technical scheme to solve above-mentioned technical problem：

A kind of automobile electrically-controlled composite turning system, including control module, machine driving module, electric boosted module and electricity Control hydraulic booster module；

Shown machine driving module includes steering wheel, steering column, ball-and-nut steering gear, track rod, steering wheel angle Sensor, torque sensor and vehicle speed sensor；

Described steering column one end is fixedly linked by steering wheel angle sensor and the steering wheel, the other end and described is followed One input of global steering gear is connected；

The ball-and-nut steering gear is using the ball-and-nut steering gear with hydraulic function, its output end and the horizontal drawing of the steering The input of bar is connected；

Two output ends of the track rod are connected with two front-wheels of automobile respectively；

The torque sensor for obtaining the moment of torsion on steering column, and passes it to the control on steering column Molding block；

The steering wheel angle sensor is used to obtain the corner of steering wheel, and passes it to the control module；

The vehicle speed sensor is arranged on automobile, for obtaining the speed of automobile, and passes it to the control mould Block；

The electric boosted module include arc linear motor and reducing gear, the output end of the arc linear motor and Another input of the ball-and-nut steering gear is connected by the reducing gear；

The electric-controlled hydraulic power-assisted module includes hydraulic tank, hydraulic pump, rotary valve and hydraulic pump drive motor；

The output end of the hydraulic pump drive motor and the input of hydraulic pump are fixedly linked；

The oil-feed port of the hydraulic pump is connected with the in-line of the hydraulic tank, fuel-displaced port and the rotary valve enter Hydraulic fluid port pipeline is connected；

The oil-out of the rotary valve is connected with the return line of the hydraulic tank, high-pressure oil outlet and the circulating ball are turned to The oil inlet pipeline of device is connected, low pressure oil-out is connected with the oil-out pipeline of the ball-and-nut steering gear；

The control module respectively with vehicle speed sensor, torque sensor, steering wheel angular displacement sensor, arc straight-line electric Machine, hydraulic pump drive motor are electrically connected, for according to GES, torque sensor signal, the steering wheel angle for receiving Signal control arc linear motor, the work of hydraulic pump drive motor.

As a kind of automobile electrically-controlled further prioritization scheme of composite turning system of the present invention, the ball-and-nut steering gear bag Containing pitman arm, tooth fan, steering screw and steering nut；

Described steering screw one end is connected with the lower end of steering column, on the screw thread and the steering nut on steering screw The screw thread place of nibbling is provided with the steel ball chain of circulation；

Gear on the outside of the steering nut is engaged with tooth fan；

The axle center of tooth fan is connected with one end of pitman arm, the other end of the pitman arm and the horizontal drawing of the steering The input of bar is connected.

The invention also discloses a kind of Multipurpose Optimal Method based on the automobile electrically-controlled composite turning system, comprising following Step：

Step 1), automatically controlled composite turning system model, Full Vehicle Dynamics model and energy consumption model are set up, wherein, it is described Automatically controlled composite turning system model includes steering wheel model, input and output shaft model, hydraulic pump model, circulation spherical model, motor Model, tire model；

Step 2), using the steering response of automobile electrically-controlled composite turning system, steering sensitivity and steering energy consumption as electricity The Performance Evaluating Indexes of composite turning system are controlled, steering response, steering sensitivity is set up, is turned to energy consumption these three performance evaluations and refer to Target quantitative formula；

Step 3), using steering response, steering sensitivity, energy consumption is turned to as optimization aim, with power steering magnitude range With steering sensitivity as constraints, using the frequency domain energy average value of information of road surface effective frequency range as steering response, The optimizing evaluation function of steering sensitivity；

Step 4), by steering screw centre-to-centre spacing r_a, tooth fan pitch radius r_p, steering column stiffness K_s, arc linear motor it is equivalent Rotary inertia J_m2, hydraulic pump drive motor equivalent moment of inertia J_m1, steering nut effective area A_P, tooth fan rotary inertia J_cs、 Hydraulic pump stator thickness B is used as the design variable for being combined automatically controlled steering；

Step 5), by isight optimization softwares, the algorithms of NSGA- II using fused cell film optimized algorithm turn to compound Optimized to the design variable of system, draw optimal pareto disaggregation according to optimum results, and choose optimal solution of compromising；

The algorithms of NSGA- II of the fused cell film optimized algorithm are comprised the following steps that：

Step 5.1), coding：

Span according to design variable and constraints limitation, obtain the feasible solution data of solution space, and by its table The floating type structured data of search space is shown as, the various combination of these string structure data is to constitute different feasible solutions；

Step 5.2), produce initial population：

To randomly generate, for the t=0 moment, it is P that the first generation is individual to initial population₀, population number is N, is specifically randomly generated Feasible solution X_iFor:

X_i=rand (0,1) (X_max-X_min)+X_min

X_maxIt is the coboundary of feasible solution scope, X_minIt is the lower boundary of feasible solution scope；

Step 5.3), fitness is calculated：

The feasible solution that will be obtained substitutes into object function, and resulting target function value corresponds to fitness, target function value More excellent corresponding individuality is used as defect individual；

Step 5.4), selection, intersection, sequence

M defect individual is chosen by tournament method from previous generation colony, M to initial generation is individual, according to miscellaneous Hand over operator to be calculated, produce new population：

P₁ ^new=w₁P₁+(1-w₁)P₂

P₂ ^new=w₂P₂+(1-w₂)P₁

In formula, P₁、P₂It is the two father's individualities randomly selected from population；P₁ ^new、P₂ ^newIt is to be produced by crossover operator Two new individuals, w₁、w₂It is two random numbers randomly generated on [0,1]；

In the new population that hybridization computing is produced, the mutation operator for being given as the following formula carries out mutation operation：

In formula, V is the Mutation parameter chosen, V^newIt is the parameter after variation, sign takes 0 or 1, b at random_up、b_lbRespectively The upper bound of parameter value and lower bound, r are the random number randomly generated on [0,1], and t=gc/gm is the mark of Evolution of Population, its In, g_cIt is population when the algebraically of evolution, g_mIt is the maximum evolutionary generation of population；

Obtain population Q of new generation_tAfterwards, by merging P_tAnd Q_tProduce combination population R_t=P_t∪Q_t；

Finally, using non-dominated ranking method to R_tMiddle individuality is ranked up, and selects M individual composition population of new generation P′_t+1；

Step 5.5), optimizing：

By P_t′₊₁In the individual initial population as cell membrane optimized algorithm carry out optimizing, according to non-dominated ranking and Population dividing is that liposoluble substance, high concentration non-fat-soluble material and low concentration are non-by fitness level height, crowding distance Liposoluble substance；

The parameter of automatically controlled composite turning system is optimized by cell membrane optimized algorithm, obtains multiple-objection optimization disaggregation The solution of gained is concentrated into individual and P ' afterwards_t+1Be merged into new population, using in the algorithms of NSGA- II with elitism strategy based on gathering around The non-dominated ranking method for squeezing degree is ranked up, and obtains new population P_t+1；

Step 5.6), circulation step 5.3) to step 5.5), until number of iterations is equal to default greatest iteration number, otherwise, Proceed iteration, t=t+1；

Step 5.7), decode obtaining optimal Pareto optimization disaggregation, and choose optimal appropriate according to Pareto disaggregation Association's solution.

Further optimize as a kind of Multipurpose Optimal Method based on the automobile electrically-controlled composite turning system of the present invention Scheme, step 2) described in the quantitative formula of steering response be：

In formula, r_aTo turn to pitch in ball-and-nut steering gear away from r_pIt is tooth fan pitch radius in ball-and-nut steering gear, K_sTo turn to column stiffness；T_hS () is steering wheel input torque, T_rS () is the drag torque of steering column output shaft, s is laplace Operator；

θ_rIt is steering screw corner, J_eIt is the equivalent moment of inertia of reducing gear and steering screw, J_m2It is arc straight-line electric Machine equivalent moment of inertia, n₂It is the ratio between wheel steering angle and ball-and-nut steering gear steering screw corner, n_e2For steering screw angle with The ratio between arc linear motor corner, J_m1It is hydraulic pump drive motor equivalent moment of inertia, n_e1It is screw rod angle and hydraulic pump drive The ratio between motor corner, r_aIt is the centre-to-centre spacing of screw rod power, A_PIt is the effective area of steering nut, q is hydraulic pump discharge, B_m2It is arc The equivalent viscous damping ratio of linear electric motors, B_m1It is the equivalent viscous damping ratio of hydraulic pump drive motor, ρ is that hydraulic oil is close Degree, N is rotary valve valve port number, and P is steering screw pitch, C_qIt is discharge coefficient, A₁It is the oily discharge area in rotary valve valve port gap, K_a It is arc linear motor moment coefficient, K is arc linear motor power-assisted coefficient, n_m2It is arc linear motor gearratio, n_m1It is liquid Press pump motor gearratio, m_lmIt is steering nut equivalent mass, J_csFor tooth fans rotary inertia, B is hydraulic pump stator thickness, R₂ It is hydraulic pump stator major axis radius, R₁It is hydraulic pump stator minor axis radius, Z is the hydraulic pump number of blade, and t is thick hydraulic pressure pump blade Degree；B_lm、B_csThe viscosity that respectively steering nut, tooth are fanned, θ_csFor tooth fans corner, T_csFor tooth fans torque, T_pIt is steering drag Equivalent moment of the square on rocker arm shaft.

Further optimize as a kind of Multipurpose Optimal Method based on the automobile electrically-controlled composite turning system of the present invention Scheme, step 2) described in steering sensitivity quantitative formula be：

In formula：

Q₆=B₄X₂

Q₅=B₄Y₂+B₃X₂

Q₄=B₄Z₂+B₃Y₂+B₂X₂

Wherein,

A₂=-I_xzL_βY_δ+I_xzL_δY_β-I_xN_βY_δ+I_xN_δY_β+muL_pN_δ+m_shL_βN_δ-m_shL_δN_β

A₁=L_pN_βY_δ-L_pN_δY_β-muL_δN_φ+muL_φN_δ+m_shuN_δY_φ-m_shuN_φY_δ

A₀=-L_βN_φY_δ+L_βN_δY_φ-L_δN_βY_φ+L_δN_φY_β+L_φN_βY_δ-L_φN_δY_β

B₁=I_zL_βY_φ-I_zL_φY_β+I_xzN_βY_φ-I_xzN_φY_β-L_pN_βY_r+L_pN_rY_β

+muL_pN_β-muL_φN_r+muL_rN_φ+m_shuN_φY_r-m_shuN_rY_φ

B₀=L_βN_φY_r-L_βN_rY_φ-L_φN_βY_r+L_φN_rY_β+L_rN_βY_φ-L_rN_φY_β

-muL_βN_φ+muL_φN_β+m_shuN_βY_φ-m_shuN_φY_β

F₁=-I_zL_δY_φ+I_zL_φY_δ-I_xzN_δY_φ+I_xzN_φY_δ+L_pN_δY_r-L_pN_rY_δ-muL_pN_δ

F₀=-L_δN_φY_r+L_δN_rY_φ+L_φN_δY_r-L_φN_rY_δ-L_rN_δY_φ+L_rN_φY_δ

+muL_δN_φ-muL_φN_δ+m_shuN_φY_δ-m_shuN_δY_φ

N_β=-a (k₁+k₂)+b(k₃+k₄)

N_φ=-aE₁(k₁+k₂)+bE₂(k₃+k₄)

N_δ=a (k₁+k₂)；

Y_β=-(k₁+k₂+k₃+k₄)

Y_φ=-(k₁+k₂)E₁-(k₃+k₄)E₂

Y_δ=k₁+k₂；

L_β=-(k₁+k₂+k₃+k₄)h

L_θ=-[(C₂₁-C₂₂)a+(C₂₃-C₂₄)b]d

L_δ=(k₁+k₂)h

L_p=-(D₂₁+D₂₂+D₂₃+D₂₄)d²

L_e=-[(D₂₁-D₂₂)a+(D₂₃-D₂₄)b]d

θ_hS () is through the steering wheel angle after Laplace transform, ω_rS () is through the yaw angle speed after Laplace transform Degree, n is gearratio of the output shaft to front-wheel, and a is automobile barycenter to front axle distance, and u is automobile speed, and d is the wheelspan of vehicle 1/2, E₁It is roll steer coefficient, k₁、k₂The respectively cornering stiffness of automobile the near front wheel and off-front wheel；H is the rolling moment arm of automobile；M is The complete vehicle quality of automobile；m_sIt is the spring carried mass of automobile；I_xIt is the sprung mass of automobile to the rotary inertia of x-axis；I_yIt is automobile Rotary inertia of the sprung mass to y-axis；I_zIt is the sprung mass of automobile to the rotary inertia of z-axis；I_xzIt is the sprung mass of automobile To x, the product of inertia of z-axis；E₁It is the preceding roll steer coefficient of automobile；E₂It is the rear roll steer coefficient of automobile；C_a1It is automobile Front suspension QS angular rigidity；C_a2It is the rear suspension QS angular rigidity of automobile；C21, C22 are respectively a left side for automobile Front suspension rigidity and right front suspension rigidity；C23, C24 are respectively the left rear suspension rigidity and right rear suspension rigidity of automobile；D₂₁、D₂₂ The respectively left front suspension damping coefficient and right front suspension damped coefficient of automobile；D₂₃、D₂₄The respectively left rear suspension damping of automobile Coefficient and right rear suspension damped coefficient.

Further optimize as a kind of Multipurpose Optimal Method based on the automobile electrically-controlled composite turning system of the present invention Scheme, step 2) described in turn to energy consumption quantitative formula be：

In formula, E_lossIt is system total energy consumption power, P_ECU-lossFor ECU consumes power, P_m1-lossHydraulic pump drive motor is damaged Wasted work rate, P_m2-lossIt is arc linear motor loss power, P_v-lossRotary valve loss power, P_p-lossIt is hydraulic pump loss power, U_A It is hydraulic pump drive motor work effective voltage, I_AIt is hydraulic pump drive current of electric, U_SIt is hydraulic pump drive motor power electricity Pressure, R_elecIt is the resistance on the non-armature supply of hydraulic pump drive motor, Q_sIt is hydraulic pump flow, P_eIt is the work(of arc linear motor Rate.

Further optimize as a kind of Multipurpose Optimal Method based on the automobile electrically-controlled composite turning system of the present invention Scheme, step 3) described in information of road surface effective frequency range be 0 to 40Hz；

The evaluation function of road feel is：

The evaluation index of sensitivity is：

Be combined automatically controlled steering multiple-objection optimization target be：

The present invention uses above technical scheme compared with prior art, with following technique effect：

1) to possess good road feel, power steering characteristics design adjustable excellent for present invention synthesis Electro-Hydraulic Power Steering System Point and the relatively low advantage of electric power steering energy consumption, meanwhile, the combination of two kinds of assist types also overcomes two kinds of force aid systems The less shortcoming of power-assisted scope, its flexible assist type can both be provided in low-speed big by electric-hydraulic combined power-assisted Suitable power-assisted size, again can be in the small moment of torsion of high speed with the pure electric boosted economy for improving steering, can also be Under different drive demands in rational proportion composite turning system electro-hydraulic power-assisted participation ratio, for driver provides more comfortable Improved on the basis of operating experience and turn to economy.

2) present invention considers the energy ezpenditure during motor turning, and allowing for driver's steering feeling is received, and proposes electricity The main performance evaluation index of composite turning system is controlled, and sets up its quantitative formula；It is sensitive with steering steering response, steering Degree, steering energy consumption are optimization aim, and the multiple parameters to composite turning system carry out multi-objective optimization design of power so that steering Ensure that driver obtains good steering feel with less energy ezpenditure.

3) automatically controlled composite turning system Multipurpose Optimal Method proposed by the present invention, many mesh are implanted into by cell membrane optimization method In mark optimized algorithm NSGA- II.The method is selected the individuality in population using multi-objective Genetic mechanism, is intersected, is made a variation Operation, the breadth first search for carrying out the overall situation is transported to the of new generation individual of optimization formation using cell membrane optimized algorithm according to cell membrane Opinion in the wrong carries out local optimal searching, realizes the global optimization of population and the cooperative development of local discovery learning, can be with larger journey The range of the globally optimal solution search of the raising algorithm of degree and the depth of local optimal solution search, improve convergence, enter The robust stability of the algorithm that one step is improved, so as to improve the multiple-objection optimization efficiency and optimization effect of automatically controlled composite turning system Really.

Brief description of the drawings

Fig. 1 is automatically controlled composite turning system construction drawing；

Fig. 2 is automatically controlled composite turning system optimization method flow chart；

Fig. 3 is the algorithm flow charts of NSGA- II of fused cell film optimized algorithm.

In figure, 1- steering wheels, 2- steering wheel angle sensors, 3- steering columns, 4- torque sensors, 5- rotary valves, 6- hydraulic pressure Pump, 7- hydraulic pump drive motors, 8- return lines, 9- in-lines, 10- hydraulic tanks, 11- track rods, 12- circulating balls turn To device, 12.1- pitman arms, 12.2- rack tooths fan, 12.3- steering screws, 12.4- steering nuts, 13- reducing gears, 14- Arc linear motor, 15- wheels.

Specific embodiment

Technical scheme is described in further detail below in conjunction with the accompanying drawings：

As shown in figure 1, the invention discloses a kind of automobile electrically-controlled composite turning system, including control module (ECU), machinery Transmission module, electric boosted module and electric-controlled hydraulic power-assisted module.

Shown machine driving module includes steering wheel, steering column, ball-and-nut steering gear, track rod, steering wheel angle Sensor, torque sensor and vehicle speed sensor；

Described steering column one end is fixedly linked by steering wheel angle sensor and the steering wheel, the other end and described is followed One input of global steering gear is connected；

The ball-and-nut steering gear is using the ball-and-nut steering gear with hydraulic function, its output end and the horizontal drawing of the steering The input of bar is connected；

Two output ends of the track rod are connected with two front-wheels of automobile respectively；

The torque sensor for obtaining the moment of torsion on steering column, and passes it to the control on steering column Molding block；

The steering wheel angle sensor is used to obtain the corner of steering wheel, and passes it to the control module；

The vehicle speed sensor is arranged on automobile, for obtaining the speed of automobile, and passes it to the control mould Block；

The electric boosted module include arc linear motor and reducing gear, the output end of the arc linear motor and Another output end of the ball-and-nut steering gear is connected by the reducing gear；

The electric-controlled hydraulic power-assisted module includes hydraulic tank, hydraulic pump, rotary valve and hydraulic pump drive motor；

The output end of the hydraulic pump drive motor and the input of hydraulic pump are fixedly linked；

The oil-feed port of the hydraulic pump is connected with the in-line of the hydraulic tank, fuel-displaced port and the rotary valve enter Hydraulic fluid port pipeline is connected；

The oil-out of the rotary valve is connected with the return line of the hydraulic tank, high-pressure oil outlet and the circulating ball are turned to The oil inlet pipeline of device is connected, low pressure oil-out is connected with the oil-out pipeline of the ball-and-nut steering gear；

The control module (ECU) respectively with vehicle speed sensor, torque sensor, steering wheel angular displacement sensor, arc Linear electric motors, hydraulic pump drive motor are electrically connected, for according to GES, torque sensor signal, the direction for receiving Disk angular signal control arc linear motor, the work of hydraulic pump drive motor.

The ball-and-nut steering gear includes pitman arm, tooth bar, tooth fan, steering screw and steering nut, under steering column End is joined directly together with the input shaft of ball-and-nut steering gear, and input shaft is connected by circulating ball with tooth bar, and tooth bar is directly nibbled with tooth fan Displacement is passed to pitman arm by merging, and track rod is driven by pitman arm, meanwhile, hydraulic oil passes through oil pipe and circulating ball The oil-feed oil-out of steering gear is connected, and two hydraulic fluid ports are communicated with ball-and-nut steering gear or so oil cylinder chamber respectively, by hydraulic cylinder cavity The pressure difference of body provides hydraulic booster to turn to.

The automatically controlled composite turning system of the present embodiment is compared to traditional Electro-Hydraulic Power Steering System, electric power steering system System, composite turning system has taken into account both excellent road feel, the more preferable advantages of economy, while it is smaller to overcome both power-assisted scopes Shortcoming.Electric-hydraulic combined steering, by different electro-hydraulic participation ratios, is driver while ensureing to turn to economy More preferable driving experience is provided.

The invention also discloses a kind of optimization method based on the automatically controlled composite turning system, the modeling software for being used is MATLAB-simulink, optimization software is isight, as shown in Fig. 2 comprising the following steps that：

Step 1), foundation《The design studies of Electro-Hydraulic Power Steering System》(monarch Mr. Zhang, Jiangsu University),《Electronic liquid Pressure servo steering system control strategy and its energy consumption analysis method》(Su Jiankuan etc., machine design and manufacture),《Before automobile active Rotate and control research to system force and displacement coupling》(Li Yijun, Nanjing Aero-Space University) method disclosed in document, sets up electricity Control composite turning system model, Full Vehicle Dynamics model and energy consumption model, wherein, automatically controlled composite turning system model includes turning It is automatically controlled by setting up to disk model, input and output shaft model, hydraulic pump model, circulation spherical model, motor model, tire model Composite turning system model, is that follow-up automatically controlled composite turning system emulation and optimization lay the foundation；

Step 2), using the steering response of automobile electrically-controlled composite turning system, steering sensitivity and steering energy consumption as electricity The Performance Evaluating Indexes of composite turning system are controlled, and sets up three quantitative formulas of Performance Evaluating Indexes：

Wherein, the quantitative formula of steering response is：

r_aTo turn to pitch in ball-and-nut steering gear away from r_pIt is tooth fan pitch radius, K in ball-and-nut steering gear_sTo turn To column stiffness；T_hS () is steering wheel input torque, T_rS () is the drag torque of steering column output shaft, s is laplace operators；

θ_rIt is steering screw corner, J_eIt is the equivalent moment of inertia of reducing gear and steering screw, J_m2It is arc straight-line electric Machine equivalent moment of inertia, n₂It is the ratio between wheel steering angle and ball-and-nut steering gear steering screw corner, n_e2For steering screw angle with The ratio between arc linear motor corner, J_m1It is hydraulic pump drive motor equivalent moment of inertia, n_e1It is screw rod angle and hydraulic pump drive The ratio between motor corner, r_aIt is the centre-to-centre spacing of screw rod power, A_PIt is the effective area of steering nut, q is hydraulic pump discharge, B_m2It is arc The equivalent viscous damping ratio of linear electric motors, B_m1It is the equivalent viscous damping ratio of hydraulic pump drive motor, ρ is that hydraulic oil is close Degree, N is rotary valve valve port number, P steering screw pitch, C_qDischarge coefficient, A₁The oily discharge area of valve clearance, K_aIt is arc straight-line electric Machine moment coefficient, K is arc linear motor power-assisted coefficient, n_m2It is arc linear motor gearratio, n_m1It is hydraulic pump drive motor Gearratio, m_lmIt is steering nut equivalent mass, J_csFor tooth fans rotary inertia, B is hydraulic pump stator thickness, R₂It is stator major axis half Footpath, R₁It is stator minor axis radius, Z is vane pump blade number, and t is vane thickness；B_lm、B_csWhat respectively steering nut, tooth were fanned is viscous Property coefficient, θ_csFor tooth fans corner, T_csFor tooth fans torque, T_pThe equivalent moment for being steering resisting moment on rocker arm shaft；

Steering sensitivity quantitative formula is：

Q₆=B₄X₂

Q₅=B₄Y₂+B₃X₂

Q₄=B₄Z₂+B₃Y₂+B₂X₂

A₂=-I_xzL_βY_δ+I_xzL_δY_β-I_xN_βY_δ+I_xN_δY_β+muL_pN_δ+m_shL_βN_δ-m_shL_δN_β

A₁=L_pN_βY_δ-L_pN_δY_β-muL_δN_φ+muL_φN_δ+m_shuN_δY_φ-m_shuN_φY_δ

A₀=-L_βN_φY_δ+L_βN_δY_φ-L_δN_βY_φ+L_δN_φY_β+L_φN_βY_δ-L_φN_δY_β

B₁=I_zL_βY_φ-I_zL_φY_β+I_xzN_βY_φ-I_xzN_φY_β-L_pN_βY_r+L_pN_rY_β

+muL_pN_β-muL_φN_r+muL_rN_φ+m_shuN_φY_r-m_shuN_rY_φ

B₀=L_βN_φY_r-L_βN_rY_φ-L_φN_βY_r+L_φN_rY_β+L_rN_βY_φ-L_rN_φY_β

-muL_βN_φ+muL_φN_β+m_shuN_βY_φ-m_shuN_φY_β

F₁=-I_zL_δY_φ+I_zL_φY_δ-I_xzN_δY_φ+I_xzN_φY_δ+L_pN_δY_r-L_pN_rY_δ-muL_pN_δ

F₀=-L_δN_φY_r+L_δN_rY_φ+L_φN_δY_r-L_φN_rY_δ-L_rN_δY_φ+L_rN_φY_δ

+muL_δN_φ-muL_φN_δ+m_shuN_φY_δ-m_shuN_δY_φ

N_β=-a (k₁+k₂)+b(k₃+k₄)

N_φ=-aE₁(k₁+k₂)+bE₂(k₃+k₄)

N_δ=a (k₁+k₂)；

Y_β=-(k₁+k₂+k₃+k₄)

Y_φ=-(k₁+k₂)E₁-(k₃+k₄)E₂

Y_δ=k₁+k₂；

L_β=-(k₁+k₂+k₃+k₄)h

L_θ=-[(C₂₁-C₂₂)a+(C₂₃-C₂₄)b]d

L_δ=(k₁+k₂)h

L_p=-(D₂₁+D₂₂+D₂₃+D₂₄)d²

L_e=-[(D₂₁-D₂₂)a+(D₂₃-D₂₄)b]d

θ_hS () is through the steering wheel angle after Laplace transform, ω_rS () is through the yaw angle speed after Laplace transform Degree, n is gearratio of the output shaft to front-wheel, and a is automobile barycenter to front axle distance, and u is automobile speed, and d is the wheelspan of vehicle 1/2, E₁It is roll steer coefficient, k₁、k₂The respectively cornering stiffness of automobile the near front wheel and off-front wheel；H is the rolling moment arm of automobile；M is The complete vehicle quality of automobile；m_sIt is the spring carried mass of automobile；I_xIt is the sprung mass of automobile to the rotary inertia of x-axis；I_yIt is automobile Rotary inertia of the sprung mass to y-axis；I_zIt is the sprung mass of automobile to the rotary inertia of z-axis；I_xzIt is the sprung mass of automobile To x, the product of inertia of z-axis；E₁It is the preceding roll steer coefficient of automobile；E₂It is the rear roll steer coefficient of automobile；C_a1It is automobile Front suspension QS angular rigidity；C_a2It is the rear suspension QS angular rigidity of automobile；C21, C22 are respectively a left side for automobile Front suspension rigidity and right front suspension rigidity；C23, C24 are respectively the left rear suspension rigidity and right rear suspension rigidity of automobile；D₂₁、D₂₂ The respectively left front suspension damping coefficient and right front suspension damped coefficient of automobile；D₂₃、D₂₄The respectively left rear suspension damping of automobile Coefficient and right rear suspension damped coefficient.

Turning to energy consumption quantitative formula is：

In formula, E_lossIt is system total energy consumption power, P_ECU-lossFor ECU consumes power, P_m1-lossHydraulic pump drive motor is damaged Wasted work rate, P_m2-lossIt is arc linear motor loss power, P_v-lossRotary valve loss power, P_p-lossIt is hydraulic pump loss power, U_A It is motor work effective voltage, I_AIt is current of electric, U_SIt is supply voltage, R_elecIt is the resistance on non-armature supply, Q_sIt is hydraulic pressure Pump discharge, P_eIt is arc-shaped motor power；

Step 3), using steering response, steering sensitivity, energy consumption is turned to as optimization aim, with power steering magnitude range With steering sensitivity as constraints, with information of road surface effective frequency range (0, ω₀) frequency domain energy average value as road Sense, the optimizing evaluation function of sensitivity；

The sensitivity of steering needs to keep within the specific limits, the lifting for so contributing to pilot control to experience, And too high sensitivity can increase the tension of driver in galloping, accordingly, it would be desirable to steering sensitivity is suitable Scope it is as far as possible small, so steering sensitivity is not only as optimization aim but also as constraints.

ω in prioritization scheme₀=40Hz.

The evaluation function of road feel is converted into：

The evaluation index of sensitivity is converted into：

Therefore the multiple-objection optimization target of compound automatically controlled steering is：

Step 4), by r_aSteering screw centre-to-centre spacing, r_pTooth fan pitch radius, K_sTurn to column stiffness, J_m2Arc linear motor etc. Effect rotary inertia, J_m1Hydraulic pump drive motor equivalent moment of inertia, r_aThe centre-to-centre spacing of screw rod power, A_PThe significant surface of steering nut Product, J_csTooth fan rotary inertia, B hydraulic pump stators thickness are used as the design variable for being combined automatically controlled steering；

Step 5), by isight optimization softwares, the algorithms of NSGA- II using fused cell film optimized algorithm turn to compound Optimized to the design variable of system, draw optimal pareto disaggregation according to optimum results, and choose optimal solution of compromising.

Fig. 3 is the algorithm flow charts of NSGA- II of fused cell film optimized algorithm, is comprised the following steps that：

Step 5.1), coding：

Span according to design variable and constraints limitation, obtain the feasible solution data of solution space, and by its table The floating type structured data of search space is shown as, the various combination of these string structure data is to constitute different feasible solutions；

Step 5.2), produce initial population：

To randomly generate, for the t=0 moment, it is P that the first generation is individual to initial population₀, population number is N, is specifically randomly generated Feasible solution X_iFor:

X_i=rand (0,1) (X_max-X_min)+X_min

X_maxIt is the coboundary of feasible solution scope, X_minIt is the lower boundary of feasible solution scope；

Step 5.3), fitness is calculated：

The feasible solution that will be obtained substitutes into object function, and resulting target function value corresponds to fitness, target function value More excellent corresponding individuality is used as defect individual；

Step 5.4), selection, intersection, sequence

M defect individual is chosen by tournament method from previous generation colony, M to initial generation is individual, according to miscellaneous Hand over operator to be calculated, produce new population：

P₁ ^new=w₁P₁+(1-w₁)P₂

P₂ ^new=w₂P₂+(1-w₂)P₁

In formula：P₁、P₂It is the two father's individualities randomly selected from population；P₁ ^new、P₂ ^newIt is to be produced by crossover operator New individual, w₁、w₂It is the random number randomly generated on [0,1]；

In the new population that hybridization computing is produced, the mutation operator for being given as the following formula carries out mutation operation：

In formula：V is the Mutation parameter chosen, V^newIt is the parameter after variation, sign takes 0 or 1, b at random_up、b_lbRespectively The upper bound of parameter value and lower bound, r are the random number randomly generated on [0,1], and t=gc/gm is the mark of Evolution of Population, its In, g_cIt is population when the algebraically of evolution, g_mIt is the maximum evolutionary generation of population；

Population Q of new generation is obtained with this_t, by merging P_tAnd Q_tProduce combination population R_t=P_t∪Q_t；

Using non-dominated ranking method to R_tMiddle individuality is ranked up, and selects M individual composition population P ' of new generation_t+1。

Step 5.5), cell membrane optimized algorithm optimizing：

By P '_t+1In the individual initial population as cell membrane optimized algorithm carry out optimizing, according to non-dominated ranking and Population dividing is that liposoluble substance, high concentration non-fat-soluble material and low concentration are non-by fitness level height, crowding distance Liposoluble substance.The parameter of automatically controlled composite turning system is optimized by cell membrane optimized algorithm, obtains multiple-objection optimization Disaggregation.The solution of gained is concentrated into individual and P '_t+1Be merged into new population, using in the algorithms of NSGA- II with elitism strategy based on The non-dominated ranking method of crowding is ranked up, and obtains new population P_t+1。

Step 5.6), circulation step 5.3) to step 5.5) default greatest iteration number is equal to until number of iterations, otherwise, after It is continuous to be iterated, t=t+1.

Step 5.7), decode obtaining optimal Pareto optimization disaggregation, and choose optimal appropriate according to Pareto disaggregation Association's solution.

Those skilled in the art of the present technique it is understood that unless otherwise defined, all terms used herein (including skill Art term and scientific terminology) have with art of the present invention in those of ordinary skill general understanding identical meaning.Also It should be understood that those terms defined in such as general dictionary should be understood that with the context of prior art in The consistent meaning of meaning, and unless defined as here, will not be explained with idealization or excessively formal implication.

Above-described specific embodiment, has been carried out further to the purpose of the present invention, technical scheme and beneficial effect Describe in detail, should be understood that and the foregoing is only specific embodiment of the invention, be not limited to this hair Bright, all any modification, equivalent substitution and improvements within the spirit and principles in the present invention, done etc. should be included in the present invention Protection domain within.

Claims (7)

1. a kind of automobile electrically-controlled composite turning system, it is characterised in that including control module, machine driving module, electric boosted Module and electric-controlled hydraulic power-assisted module；

Shown machine driving module includes steering wheel, steering column, ball-and-nut steering gear, track rod, steering wheel angle sensing Device, torque sensor and vehicle speed sensor；

Described steering column one end is fixedly linked by steering wheel angle sensor and the steering wheel, the other end and the circulating ball One input of steering gear is connected；

The ball-and-nut steering gear using the ball-and-nut steering gear with hydraulic function, its output end and the track rod Input is connected；

Two output ends of the track rod are connected with two front-wheels of automobile respectively；

The torque sensor for obtaining the moment of torsion on steering column, and passes it to the control mould on steering column Block；

The steering wheel angle sensor is used to obtain the corner of steering wheel, and passes it to the control module；

The vehicle speed sensor is arranged on automobile, for obtaining the speed of automobile, and passes it to the control module；

The electric boosted module includes arc linear motor and reducing gear, the output end of the arc linear motor and described Another input of ball-and-nut steering gear is connected by the reducing gear；

The electric-controlled hydraulic power-assisted module includes hydraulic tank, hydraulic pump, rotary valve and hydraulic pump drive motor；

The output end of the hydraulic pump drive motor and the input of hydraulic pump are fixedly linked；

The oil-feed port of the hydraulic pump is connected with the in-line of the hydraulic tank, the oil inlet of fuel-displaced port and the rotary valve Pipeline is connected；

The oil-out of the rotary valve is connected with the return line of the hydraulic tank, high-pressure oil outlet and the ball-and-nut steering gear Oil inlet pipeline is connected, low pressure oil-out is connected with the oil-out pipeline of the ball-and-nut steering gear；

The control module respectively with vehicle speed sensor, torque sensor, steering wheel angular displacement sensor, arc linear motor, Hydraulic pump drive motor is electrically connected, for according to GES, torque sensor signal, the steering wheel angle signal for receiving Control arc linear motor, the work of hydraulic pump drive motor.

2. automobile electrically-controlled composite turning system according to claim 1, it is characterised in that the ball-and-nut steering gear is included Pitman arm, tooth fan, steering screw and steering nut；

Described steering screw one end is connected with the lower end of steering column, the screw thread on screw thread and the steering nut on steering screw The place of nibbling is provided with the steel ball chain of circulation；

Gear on the outside of the steering nut is engaged with tooth fan；

The axle center of tooth fan is connected with one end of pitman arm, the other end of the pitman arm and the track rod Input is connected.

3. the Multipurpose Optimal Method of the automobile electrically-controlled composite turning system being based on described in claim 2, it is characterised in that include Following steps：

Step 1), automatically controlled composite turning system model, Full Vehicle Dynamics model and energy consumption model are set up, wherein, it is described automatically controlled Composite turning system model include steering wheel model, input and output shaft model, hydraulic pump model, circulation spherical model, motor model, Tire model；

Step 2), using the steering response of automobile electrically-controlled composite turning system, steering sensitivity and energy consumption is turned to as automatically controlled multiple The Performance Evaluating Indexes of steering are closed, steering response, steering sensitivity is set up, is turned to energy consumption these three Performance Evaluating Indexes Quantitative formula；

Step 3), using steering response, steering sensitivity, energy consumption is turned to as optimization aim, with power steering magnitude range and turn To sensitivity as constraints, using the frequency domain energy average value of information of road surface effective frequency range as steering response, turn to The optimizing evaluation function of sensitivity；

Step 4), by steering screw centre-to-centre spacing r_a, tooth fan pitch radius r_p, steering column stiffness K_s, arc linear motor Equivalent Rotational Inertia J_m2, hydraulic pump drive motor equivalent moment of inertia J_m1, steering nut effective area A_P, tooth fan rotary inertia J_cs, hydraulic pressure Pump stator thickness B is used as the design variable for being combined automatically controlled steering；

Step 5), by isight optimization softwares, using the algorithms of NSGA- II of fused cell film optimized algorithm to composite turning system The design variable of system is optimized, and draws optimal pareto disaggregation according to optimum results, and choose optimal solution of compromising；

The algorithms of NSGA- II of the fused cell film optimized algorithm are comprised the following steps that：

Step 5.1), coding：

Span and constraints limitation according to design variable, obtains the feasible solution data of solution space, and be expressed as The floating type structured data of search space, the various combination of these string structure data is to constitute different feasible solutions；

Step 5.2), produce initial population：

To randomly generate, for the t=0 moment, it is P that the first generation is individual to initial population₀, population number is N, and what is specifically randomly generated can Row solution X_iFor:

X_i=rand (0,1) (X_max-X_min)+X_min

X_maxIt is the coboundary of feasible solution scope, X_minIt is the lower boundary of feasible solution scope；

Step 5.3), fitness is calculated：

The feasible solution that will be obtained substitutes into object function, and resulting target function value corresponds to fitness, and target function value is more excellent Corresponding individuality is used as defect individual；

Step 5.4), selection, intersection, sequence

M defect individual is chosen by tournament method from previous generation colony, M to initial generation is individual, is calculated according to hybridization Son is calculated, and produces new population：

P₁ ^new=w₁P₁+(1-w₁)P₂

P₂ ^new=w₂P₂+(1-w₂)P₁

In formula, P₁、P₂It is the two father's individualities randomly selected from population；P₁ ^new、P₂ ^newIt is two produced by crossover operator New individual, w₁、w₂It is two random numbers randomly generated on [0,1]；

In the new population that hybridization computing is produced, the mutation operator for being given as the following formula carries out mutation operation：

$V^{new}=\left\{\begin{array}{cc}V+(b_{up}-V){\[r(1-t)\]}^2,& sign=0\\ V-(V-b_{lb}){\[r(1-t)\]}^2,& sign=1\end{array}\right.$

In formula, V is the Mutation parameter chosen, V^newIt is the parameter after variation, sign takes 0 or 1, b at random_up、b_lbRespectively parameter takes The upper bound of value and lower bound, r are the random number randomly generated on [0,1], and t=gc/gm is the mark of Evolution of Population, wherein, g_cIt is Population is when the algebraically of evolution, g_mIt is the maximum evolutionary generation of population；

Obtain population Q of new generation_tAfterwards, by merging P_tAnd Q_tProduce combination population R_t=P_t∪Q_t；

Finally, using non-dominated ranking method to R_tMiddle individuality is ranked up, and selects M individual composition population P ' of new generation_t+1；

Step 5.5), optimizing：

By P '_t+1In the individual initial population as cell membrane optimized algorithm carry out optimizing, according to non-dominated ranking and adaptation Population dividing is liposoluble substance, high concentration non-fat-soluble material and the non-liposoluble of low concentration by degree level height, crowding distance Property material；

The parameter of automatically controlled composite turning system is optimized by cell membrane optimized algorithm, is incited somebody to action after obtaining multiple-objection optimization disaggregation The solution of gained concentrates individual and P '_t+1Be merged into new population, using in the algorithms of NSGA- II with elitism strategy based on crowding Non-dominated ranking method be ranked up, obtain new population P_t+1；

Step 5.6), circulation step 5.3) to step 5.5), until number of iterations is equal to default greatest iteration number, otherwise, continue It is iterated, t=t+1；

Step 5.7), decode obtaining optimal Pareto optimization disaggregation, and optimal solution of compromising is chosen according to Pareto disaggregation.

4. the Multipurpose Optimal Method of the automobile electrically-controlled composite turning system being based on described in claim 3, it is characterised in that step 2) quantitative formula of steering response described in is：

$\frac{T_h\left(s\right)}{T_r\left(s\right)}=\frac{r_a{K}_s}{r_p}\·\frac{1}{X_1{s}^2+Y_{1}s+Z_1}$

In formula, r_aTo turn to pitch in ball-and-nut steering gear away from r_pIt is tooth fan pitch radius, K in ball-and-nut steering gear_sFor Turn to column stiffness；T_hS () is steering wheel input torque, T_rS () is the drag torque of steering column output shaft, s is laplace operators；

$\left\{\begin{array}{c}{X}_1=J_m{\stackrel{\·\·}{\mathrm{\θ}}}_r+J_{m2}\·n_2\·n_{e2}+J_{m1}\·n_{e1}\·\frac{r_a\·A_P}{q}\\ Y_1=B_m{\stackrel{\·}{\mathrm{\θ}}}_r+B_{m2}\·n_2\·n_{e2}+B_{m1}\·n_{e1}\·\frac{r_a\·A_P}{q}+\frac{r_a{A_P}^2\mathrm{\ρ}qNP}{4\mathrm{\π}{(C_q\·A_1)}^2}\\ Z_1=K_s{\mathrm{\θ}}_r+K_a{\mathrm{KK}}_s(n_{m2}\·n_2+\frac{r_a{A}_p}{q}{n}_{m1})\\ J_m=J_e+m_{lm}\·r_a\frac{P}{2\mathrm{\π}}+J_{cs}\·\frac{r_a}{{r_p}^2}\·\frac{P}{2\mathrm{\π}}\\ B_m=B_{1g}+B_{lm}\·r_a\frac{P}{2\mathrm{\π}}+B_{cs}\·\frac{r_a}{{r_p}^2}\·\frac{P}{2\mathrm{\π}}\\ q=2B\[\frac{1}{2}(R_2^2-R_1^2)\mathrm{\π}-(R_2-R_1)Zt\]\end{array}\right.$

θ_rIt is steering screw corner, J_eIt is the equivalent moment of inertia of reducing gear and steering screw, J_m2For arc linear motor is equivalent Rotary inertia, n₂It is the ratio between wheel steering angle and ball-and-nut steering gear steering screw corner, n_e2For steering screw angle and arc are straight The ratio between line motor corner, J_m1It is hydraulic pump drive motor equivalent moment of inertia, n_e1It is that screw rod angle and hydraulic pump drive motor turn The ratio between angle, r_aIt is the centre-to-centre spacing of screw rod power, A_PIt is the effective area of steering nut, q is hydraulic pump discharge, B_m2It is arc straight-line electric The equivalent viscous damping ratio of machine, B_m1It is the equivalent viscous damping ratio of hydraulic pump drive motor, ρ is hydraulic oil density, and N is to turn Valve valve port number, P is steering screw pitch, C_qIt is discharge coefficient, A₁It is the oily discharge area in rotary valve valve port gap, K_aFor arc is straight Line motor torque coefficient, K is arc linear motor power-assisted coefficient, n_m2It is arc linear motor gearratio, n_m1It is hydraulic pump drive Motor gearratio, m_lmIt is steering nut equivalent mass, J_csFor tooth fans rotary inertia, B is hydraulic pump stator thickness, R₂It is hydraulic pump Stator major axis radius, R₁It is hydraulic pump stator minor axis radius, Z is the hydraulic pump number of blade, and t is hydraulic pump vane thickness；B_lm、B_csPoint Wei not steering nut, the viscosity of tooth fan, θ_csFor tooth fans corner, T_csFor tooth fans torque, T_pIt is steering resisting moment in rocker arm shaft On equivalent moment.

5. the Multipurpose Optimal Method of the automobile electrically-controlled composite turning system being based on described in claim 4, it is characterised in that step 2) steering sensitivity quantitative formula described in is：

$\frac{{\mathrm{\ω}}_r\left(s\right)}{{\mathrm{\θ}}_h\left(s\right)}=\frac{A_3{s}^3+A_2{s}^2+A_{1}s+A_0}{Q_6{s}^6+Q_5{s}^5+Q_4{s}^4+Q_3{s}^3+Q_2{s}^2+Q_{1}s+Q_0}\·Z_1$

In formula：

Q₆=B₄X₂

Q₅=B₄Y₂+B₃X₂

Q₄=B₄Z₂+B₃Y₂+B₂X₂

$Q_3=B_3{Z}_2+B_2{Y}_2+B_1{X}_2+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}{F}_3+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}\frac{a}{V}{A}_3$

$Q_2=B_2{Z}_2+B_1{Y}_2+B_0{X}_2+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}{F}_2+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}\frac{a}{V}{A}_2+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}{E}_1{H}_2$

$Q_1=B_1{Z}_2+B_0{Y}_2+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}{F}_1+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}\frac{a}{V}{A}_1+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}{E}_1{H}_1$

$Q_0=B_0{Z}_2+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}{F}_0+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}\frac{a}{V}{A}_0+\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}{E}_1{H}_0$

$\left\{\begin{array}{c}{X}_2={\mathrm{nX}}_1\\ Y_2={\mathrm{nY}}_1\\ Z_2={\mathrm{nZ}}_1-\frac{r_a}{r_p}\·\frac{2{\mathrm{dk}}_1}{n}\end{array}\right.;$

Wherein,

$A_3=-{\mathrm{muI}}_{xz}{L}_{\mathrm{\δ}}--{\mathrm{muI}}_x{N}_{\mathrm{\δ}}+m_s^2{h}^2{\mathrm{uN}}_{\mathrm{\δ}}-m_s{\mathrm{huI}}_{xz}{Y}_{\mathrm{\δ}}$

A₂=-I_xzL_βY_δ+I_xzL_δY_β-I_xN_βY_δ+I_xN_δY_β+muL_pN_δ+m_shL_βN_δ-m_shL_δN_β

A₁=L_pN_βY_δ-L_pN_δY_β-muL_δN_φ+muL_φN_δ+m_shuN_δY_φ-m_shuN_φY_δ

A₀=-L_βN_φY_δ+L_βN_δY_φ-L_δN_βY_φ+L_δN_φY_β+L_φN_βY_δ-L_φN_δY_β

$B_4={{\mathrm{muI}}^2}_{xz}+m_s^2{h}^2{\mathrm{uI}}_z-{\mathrm{muI}}_x{I}_z$

$\begin{array}{c}{B}_3=-{I^2}_{xz}{Y}_{\mathrm{\β}}+I_x{I}_z{Y}_{\mathrm{\β}}-m_s^2{h}^2{\mathrm{uN}}_r+m_s{\mathrm{hI}}_z{L}_{\mathrm{\β}}+m_s{\mathrm{hI}}_{xz}{N}_{\mathrm{\β}}+m_s{\mathrm{huI}}_{xz}{Y}_r\\ +{\mathrm{muI}}_z{L}_p+{\mathrm{muI}}_{xz}{L}_r+{\mathrm{muI}}_x{N}_r\end{array}$

$\begin{array}{c}{B}_2=-I_z{L}_p{Y}_{\mathrm{\β}}+I_{xz}{L}_{\mathrm{\β}}{Y}_r-I_{xz}{L}_r{Y}_{\mathrm{\β}}+I_x{N}_{\mathrm{\β}}{Y}_r-I_x{N}_r{Y}_{\mathrm{\β}}+m_s^2{h}^2{\mathrm{uN}}_{\mathrm{\β}}\\ +{\mathrm{muI}}_{xz}{N}_{\mathrm{\φ}}-{\mathrm{muI}}_{xz}{L}_{\mathrm{\β}}+{\mathrm{muI}}_z{L}_{\mathrm{\φ}}-{\mathrm{muI}}_x{N}_{\mathrm{\β}}-{\mathrm{muL}}_p{N}_r\\ -m_s{\mathrm{hL}}_{\mathrm{\β}}{N}_r+m_s{\mathrm{hL}}_r{N}_{\mathrm{\β}}-m_s{\mathrm{huI}}_{xz}{Y}_{\mathrm{\β}}+m_s{\mathrm{huI}}_z{Y}_{\mathrm{\φ}}\end{array}$

B₁=I_zL_βY_φ-I_zL_φY_β+I_xzN_βY_φ-I_xzN_φY_β-L_pN_βY_r+L_pN_rY_β

+muL_pN_β-muL_φN_r+muL_rN_φ+m_shuN_φY_r-m_shuN_rY_φ

B₀=L_βN_φY_r-L_βN_rY_φ-L_φN_βY_r+L_φN_rY_β+L_rN_βY_φ-L_rN_φY_β

-muL_βN_φ+muL_φN_β+m_shuN_βY_φ-m_shuN_φY_β

F₃=I² _xzY_δ-I_xI_zY_δ-m_shI_zL_δ-m_shI_xzN_δ

$\begin{array}{c}{F}_2=I_z{L}_p{Y}_{\mathrm{\δ}}-I_{xz}{L}_{\mathrm{\δ}}{Y}_r+I_{xz}{L}_r{Y}_{\mathrm{\δ}}-I_x{N}_{\mathrm{\δ}}{Y}_r+I_x{N}_r{Y}_{\mathrm{\δ}}\\ +{\mathrm{muI}}_{xz}{L}_{\mathrm{\δ}}+{\mathrm{muI}}_x{N}_{\mathrm{\δ}}-m_s^2{h}^2{\mathrm{uN}}_{\mathrm{\δ}}+m_s{\mathrm{hL}}_{\mathrm{\δ}}{N}_r-m_s{\mathrm{hL}}_r{N}_{\mathrm{\δ}}+m_s{\mathrm{huI}}_{xz}{Y}_{\mathrm{\δ}}\end{array}$

F₁=-I_zL_δY_φ+I_zL_φY_δ-I_xzN_δY_φ+I_xzN_φY_δ+L_pN_δY_r-L_pN_rY_δ-muL_pN_δ

F₀=-L_δN_φY_r+L_δN_rY_φ+L_φN_δY_r-L_φN_rY_δ-L_rN_δY_φ+L_rN_φY_δ

+muL_δN_φ-muL_φN_δ+m_shuN_φY_δ-m_shuN_δY_φ

$N_r=-\frac{a^2(k_1+k_2)+b^2(k_3+k_4)}{u}$

N_β=-a (k₁+k₂)+b(k₃+k₄)

N_φ=-aE₁(k₁+k₂)+bE₂(k₃+k₄)

N_δ=a (k₁+k₂)；

$Y_r=-\frac{(k_1+k_2)a-(k_3+k_4)b}{u}$

Y_β=-(k₁+k₂+k₃+k₄)

Y_φ=-(k₁+k₂)E₁-(k₃+k₄)E₂

Y_δ=k₁+k₂；

$L_r=-\frac{(k_1+k_2)a-(k_3+k_4)b}{u}h$

L_β=-(k₁+k₂+k₃+k₄)h

$L_{\mathrm{\φ}}=-\[(k_1+k_2)E_{1}h+(k_3+k_4)E_{2}h+(C_{21}+C_{22}+C_{23}+C_{24}+\frac{C_{a1}+C_{a2}}{d^2})d^2-m_{s}gh\]$

L_θ=-[(C₂₁-C₂₂)a+(C₂₃-C₂₄)b]d

L_δ=(k₁+k₂)h

L_p=-(D₂₁+D₂₂+D₂₃+D₂₄)d²

L_e=-[(D₂₁-D₂₂)a+(D₂₃-D₂₄)b]d

θ_hS () is through the steering wheel angle after Laplace transform, ω_rS () is through the yaw velocity after Laplace transform, n It is the gearratio of output shaft to front-wheel, a is automobile barycenter to front axle distance, and u is automobile speed, and d is the wheelspan of vehicle 1/2, E₁For Roll steer coefficient, k₁、k₂The respectively cornering stiffness of automobile the near front wheel and off-front wheel；H is the rolling moment arm of automobile；M is automobile Complete vehicle quality；m_sIt is the spring carried mass of automobile；I_xIt is the sprung mass of automobile to the rotary inertia of x-axis；I_yIt is the suspension of automobile Rotary inertia of the quality to y-axis；I_zIt is the sprung mass of automobile to the rotary inertia of z-axis；I_xzIt is the sprung mass of automobile to x, z The product of inertia of axle；E₁It is the preceding roll steer coefficient of automobile；E₂It is the rear roll steer coefficient of automobile；C_a1It is the front suspension of automobile QS angular rigidity；C_a2It is the rear suspension QS angular rigidity of automobile；C21, C22 are respectively the left front suspension of automobile Rigidity and right front suspension rigidity；C23, C24 are respectively the left rear suspension rigidity and right rear suspension rigidity of automobile；D₂₁、D₂₂Respectively The left front suspension damping coefficient and right front suspension damped coefficient of automobile；D₂₃、D₂₄Respectively the left rear suspension damped coefficient of automobile and Right rear suspension damped coefficient.

6. the Multipurpose Optimal Method of the automobile electrically-controlled composite turning system being based on described in claim 5, it is characterised in that step 2) described in turn to energy consumption quantitative formula be：

$\begin{array}{c}{E}_{loss}=P_{ECU-loss}+P_{m1-loss}+P_{m2-loss}+P_{v-loss}+P_{p-loss}\\ =U_A{I}_A+R_A{I}_A^2+\frac{U_S}{R_{elec}^2}+{\∫}_0^t{P}_e\left(t\right)\frac{dt}{t}+\frac{\mathrm{\ρ}}{8{\left(C_q{A}_1\right)}^2}{(\frac{Q_a}{4}+A_p\frac{{\mathrm{dx}}_r}{dt})}^3\\ +\frac{\mathrm{\ρ}}{8{\left(C_q{A}_2\right)}^2}{(\frac{Q_s}{4}-A_p\frac{{\mathrm{dx}}_r}{dt})}^3+\frac{\mathrm{\ρ}}{8C_q^2}\[{\left(\frac{Q_S-A_P{\stackrel{\·}{\mathrm{\θ}}}_{P}P}{A_2}\right)}^2+{\left(\frac{Q_S+A_P{\stackrel{\·}{\mathrm{\θ}}}_{P}P}{A_1}\right)}^2\]({\mathrm{qn}}_p-Q_S)\end{array}$

In formula, E_lossIt is system total energy consumption power, P_ECU-lossFor ECU consumes power, P_m1-lossHydraulic pump drive loss of electric machine work( Rate, P_m2-lossIt is arc linear motor loss power, P_v-lossRotary valve loss power, P_p-lossIt is hydraulic pump loss power, U_AIt is liquid Press pump motor work effective voltage, I_AIt is hydraulic pump drive current of electric, U_SIt is hydraulic pump drive motor power voltage, R_elecIt is the resistance on the non-armature supply of hydraulic pump drive motor, Q_sIt is hydraulic pump flow, P_eIt is the power of arc linear motor.

7. the Multipurpose Optimal Method of the automobile electrically-controlled composite turning system being based on described in claim 6, it is characterised in that step 3) information of road surface effective frequency range described in is 0 to 40Hz；

The evaluation function of road feel is：

The evaluation index of sensitivity is：

Be combined automatically controlled steering multiple-objection optimization target be：

$\left\{\begin{array}{c}Max:Wlugan\\ Min:E_{loss}Wlmd\\ \begin{array}{cc}s.t.& L_1<Wlmd<H_1\\ & L_2<zhuli<H_2\end{array}\end{array}\right..$