CN103273960B - Method for arranging power-assisted cylinders of multi-axle steering vehicle and multi-axle steering vehicle - Google Patents

Abstract

The invention discloses a multi-axle steering vehicle and a method for arranging power cylinders of the multi-axle steering vehicle, wherein the multi-axle steering vehicle comprises a plurality of steering axles, each steering axle is provided with two wheels and two power cylinders respectively used for assisting the two wheels to steer, and the method comprises the following steps: and setting the power-assisted cylinders to enable the steering power moment of the two corresponding power-assisted cylinders of each steering axle acting on the steering axle to be matched with the steering resistance moment of the steering axle. By the method, the power-assisted cylinders are arranged at proper positions, so that the steering power moment and the steering resistance moment of each steering axle are matched, the moment transmitted by the steering rod system is reduced, overlarge stress of the steering rod system caused by the moment transmission is avoided, and the safety and the reliability of the steering system are improved.

Description

Arrange method and the multi-shaft steering vehicle of the power-assisted oil cylinder of multi-shaft steering vehicle

Technical field

The present invention relates to multi-shaft steering vehicle, particularly, relate to a kind of arrange the power-assisted oil cylinder of multi-shaft steering vehicle method and use the method to arrange the multi-shaft steering vehicle of power-assisted oil cylinder.

Background technology

As shown in Figure 1, Figure 2 and Figure 3, existing mechanical type multi-axis steering system is generally made up of longitudinal driving rocker mechanism and horizontal transmission tie rod linkage and relies on hydraulic booster to realize turning to: rocker arm body is made up of rocking arm 2,5,7,10,13 and pull bar 1,4,6,8,9,11,12,14, is used for realizing the angle relation between the one-sided wheel of different steeraxle 15,16,17,18,19,20; Tie rod linkage is made up of bridge axle 154, left trapezoidal joint arm 152, the trapezoidal joint arm 157 of intermediate rod 158 and the right side, is used for realizing the angle relation between same steeraxle left wheel 151 and right wheel 156; On each steeraxle, installation one or two oil cylinders (being left and right two power-assisted oil cylinders 153,155 in figure) realize hydraulic power-assisted steering.

In order to realize best steering procedure (when turning to, all wheel flutters are all in pure rolling state or only have minimum slippage), reach the object reducing steering resisting torque and wear on tyres, for multi-shaft steering vehicle, except considering that making the extended line of same bridge left and right wheels axle will meet at same point (as shown in Figure 3) namely meets except Ackerman principle, also will consider the angle relation between different bridge wheel.

For six bridge vehicles that five bridges of Fig. 4 turn to, wherein from head to afterbody, the 4th bridge of (namely in figure from left to right) is the bridge do not turned to, remaining five bridge is steeraxle, the inside and outside corner of taking turns of each bridge obtains using the extended line of the 4th bridge as benchmark, and the inside and outside angle relation of taking turns of same steering shaft should meet Ackerman principle:

$\left\{\begin{array}{c}ctg\left({\mathrm{\β}}_{15}\right)-ctg\left({\mathrm{\α}}_{15}\right)=B/L_1\\ ctg\left({\mathrm{\β}}_{16}\right)-ctg\left({\mathrm{\α}}_{16}\right)=B/L_2\\ ctg\left({\mathrm{\β}}_{17}\right)-ctg\left({\mathrm{\α}}_{17}\right)=B/L_3\\ ctg\left({\mathrm{\β}}_{19}\right)-ctg\left({\mathrm{\α}}_{19}\right)=B/L_4\\ ctg\left({\mathrm{\β}}_{20}\right)-ctg\left({\mathrm{\α}}_{20}\right)=B/L_5\end{array}\right.---\left(1\right)$

The relation that different steeraxle the same sides wheel turning angle should meet:

$\left\{\begin{array}{c}\tan {\mathrm{\α}}_{15}/\tan {\mathrm{\α}}_{16}=L_1/L_2\\ \tan {\mathrm{\α}}_{15}/\tan {\mathrm{\α}}_{17}=L_1/L_3\\ \tan {\mathrm{\α}}_{15}/\tan {\mathrm{\α}}_{19}=L_1/L_4\\ \tan {\mathrm{\α}}_{15}/\tan {\mathrm{\α}}_{20}=L_1/L_5\end{array}\right.---\left(2\right)$

Wherein, α ₁₅to α ₂₀represent the left wheel corner of steeraxle 15 to steeraxle 20 respectively, β ₁₅to β ₂₀represent the right wheel steering angle of steeraxle 15 to steeraxle 20 respectively; In addition, the 4th steeraxle 18 is turning center line, and L1 to L5 is respectively the distance of other each steeraxles to turning center line, and B is the stub ground connection spacing of steeraxle.

As mentioned above, two wheels of each steeraxle carry out servo-steering respectively by two power-assisted oil cylinders, and the power-assisted oil cylinder of different steeraxle generally adopts the power-assisted oil cylinder of same model, and the power output of namely all power-assisted oil cylinders is all equal.Meanwhile, when wheel does not rotate, on each steeraxle, corresponding power-assisted oil cylinder is disposed on identical position, and cause the torque arm length of each power-assisted oil cylinder substantially equal or be more or less the same, therefore the steering power square of each bridge is substantially equal.But vehicle is when turning to, the steering resisting torque that steeraxle is subject to is relevant with the corner size of wheel: M α=f (α)=D × sin (C × arctan (E × α+A)), and according to Ackerman principle, the corner of the wheel of each steeraxle is not identical.This just makes the steeraxle that corner is little, and steering power moment ratio steering resisting torque is large, and unnecessary steering power square just passes through the steeraxle that steering gear connection (i.e. rocking arm, pull bar etc.) passes to other.And the steeraxle that corner is large, steering power square is less than steering resisting torque, needs the help being obtained steering power square on other steeraxle by steering gear connection.In the process of carry-over moment, steering gear connection is stressed excessive, often causes damage, reduces reliability and the safety of steering swivel system.

Summary of the invention

The object of this invention is to provide a kind of method of arranging the power-assisted oil cylinder of multi-shaft steering vehicle, with avoid steering gear connection because of carry-over moment cause stressed excessive.

To achieve these goals, the invention provides a kind of method of arranging the power-assisted oil cylinder of multi-shaft steering vehicle, described multi-shaft steering vehicle comprises multiple steeraxle, each steeraxle is provided with the power-assisted oil cylinder that two wheels and two are respectively used to two wheel steerings described in power-assisted, and described method comprises: described power-assisted oil cylinder is arranged so that the steering power square of two of each described steeraxle corresponding power-assisted oil cylinders to this steeraxle effect and the cornering resistance match by moment of described steeraxle.

The present invention also provides a kind of multi-shaft steering vehicle, described multi-shaft steering vehicle comprises multiple steeraxle, each steeraxle is provided with the power-assisted oil cylinder that two wheels and two are respectively used to two wheel steerings described in power-assisted, and described power-assisted oil cylinder is arranged by method of the present invention.

Pass through technique scheme, by method of the present invention, each power-assisted oil cylinder is arranged the steering power square and the cornering resistance match by moment that make each steeraxle in position, thus decrease the moment of steering gear connection transmission, and avoid steering gear connection because of carry-over moment cause stressed excessive, improve the safety and reliability of steering swivel system.

Other features and advantages of the present invention are described in detail in detailed description of the invention part subsequently.

Accompanying drawing explanation

Accompanying drawing is used to provide a further understanding of the present invention, and forms a part for specification sheets, is used from explanation the present invention, but is not construed as limiting the invention with detailed description of the invention one below.In the accompanying drawings:

Fig. 1 is the structural representation of longitudinal transmission that multi-shaft steering vehicle is described;

Fig. 2 is the structural representation of the horizontal transmission of the multi-shaft steering vehicle of instruction diagram 1;

Fig. 3 is the schematic diagram of the installation relation that the parts such as power-assisted oil cylinder, steeraxle are described;

Fig. 4 is the schematic diagram of the Ackerman principle that multi-shaft steering vehicle is described;

Fig. 5 illustrates that the power-assisted oil cylinder of i-th steeraxle of the present invention is arranged and turns to the schematic diagram of front and back position of articulating point relation.

Detailed description of the invention

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in detail.Should be understood that, detailed description of the invention described herein, only for instruction and explanation of the present invention, is not limited to the present invention.

In the present invention, when not doing contrary explanation, the noun of locality such as " upper and lower, left and right " of use typically refers to reference to upper and lower, left and right shown in the drawings; " inside and outside " refers to profile inside and outside relative to each parts itself.

According to an aspect of the present invention, a kind of method of arranging the power-assisted oil cylinder of multi-shaft steering vehicle is provided, described multi-shaft steering vehicle comprises multiple steeraxle, each steeraxle is provided with the power-assisted oil cylinder that two wheels and two are respectively used to two wheel steerings described in power-assisted, and described method comprises: described power-assisted oil cylinder is arranged so that the steering power square of two of each described steeraxle corresponding power-assisted oil cylinders to this steeraxle effect and the cornering resistance match by moment of described steeraxle.

By suitably arranging power-assisted oil cylinder, make steering power square and the cornering resistance match by moment of each steeraxle, can reduce steering gear connection transmission moment and avoid steering gear connection because of carry-over moment cause stressed excessive, improve the safety and reliability of steering swivel system.

Preferably, described method comprises and first sets benchmark bridge, the quantity of described steeraxle to be P, P be greater than 2 natural number, power-assisted oil cylinder corresponding for i-th steeraxle is arranged so that value minimum as the steering power square of described i-th steeraxle and the standard of cornering resistance match by moment, wherein, i is greater than the natural number that 1 is less than or equal to P, represents i-th steeraxle, m be greater than 0 natural number and represent the single wheel angle range of described benchmark bridge is divided into m numerical value, n _ijfor being the steering resisting torque of i-th steeraxle and the ratio of the steering resisting torque of described benchmark bridge described in during the jth in a described m numerical value value when the described single wheel corner of described benchmark bridge, N _ijfor two the power-assisted oil cylinders that are i-th steeraxle described in during the jth in a described m numerical value value when the described single wheel corner of described benchmark bridge to two power-assisted oil cylinders of the steering power square of described i-th steeraxle and described benchmark bridge to the ratio of the steering power square of described benchmark bridge.

Particularly, a steeraxle first can be selected as benchmark bridge, and by the angle range decile of the single wheel of benchmark bridge, such as can by the scope decile of the corner of left wheel.Such as, this angle range is-35 ° to 35 °, then can be difference decile with 1 ° by angle range, m be 70.Calculate from-35 ° | N _ij-n _ij| and sue for peace.Certainly, also can by the scope decile of the corner of right wheel.

Wherein, the steering power square of each steeraxle be the oil pressure × action section of power-assisted oil cylinder amass × power-assisted oil cylinder is to total arm of force of this steeraxle.

Due to the layout more complicated that oil pressure and the action section of power-assisted oil cylinder amass, the arm of force of preferred arrangements power-assisted oil cylinder of the present invention, namely the specification of the corresponding power-assisted oil cylinder of each steeraxle is identical with operation pressure, therefore: N _ijtwo the power-assisted oil cylinders being i-th steeraxle to two power-assisted oil cylinders of total arm of force of described i-th steeraxle and described benchmark bridge to the ratio of total arm of force of described benchmark bridge, wherein: when the corner of the described single wheel of described benchmark bridge is jth value, the total arm of force of two power-assisted oil cylinders to described i-th steeraxle of described i-th steeraxle is l _{ij α}and l _{ij β}sum, wherein, l _{ij α}for the arm of force of power-assisted oil cylinder corresponding to the left wheel of described i-th steeraxle when the corner of the described single wheel of described benchmark bridge is jth value to described i-th steeraxle, l _{ij β}for the arm of force of power-assisted oil cylinder corresponding to the right wheel of described i-th steeraxle when the corner of the described single wheel of described benchmark bridge is jth value to described i-th steeraxle; The steering resisting torque of described i-th steeraxle is M _ijα and M _ijβ sum, wherein, M _ijto be described i-th steeraxle be a jth value and the corner of the left wheel of described i-th steeraxle is α at the corner of the described single wheel of described benchmark bridge to α _jtime the resisting moment that is subject to, M _ijto be described i-th steeraxle be a jth value and the corner of the right wheel of described i-th steeraxle is β at the corner of the described single wheel of described benchmark bridge to β _jtime the resisting moment that is subject to.As mentioned above, M _ijα and M _ijβ is α respectively _jand β _jfunction, can α be used _jand β _jrepresent, such as, can with reference to method, that is: M disclosed in " heavy multi-shaft steering vehicle tire pivot stud resisting moment " (Transactions of the Chinese Society of Agricultural Engineering, volume the 10th phase October the 26th in 2010) _ijα=f (α _j)=D × sin (C × arctan (E × α _j+ A)), M _ijβ=f (β _j)=D × sin (C × arctan (E × β _j+ A)), M _ijα and M _ijβ all meets a zeroaxial relationships of increase function, and wherein, D is fitting parameter undetermined, determines the peak of curve of described increasing function; C, E are fitting parameter undetermined, and determine rigidity and the shape of described curve respectively, A is fitting parameter undetermined, determines the initial value of described curve.By the curve function of MATLAB software, obtain the numerical value of each undetermined parameter in described resisting moment functional expression according to the matching of experimental test result.Wherein, parameter D is comprised the influence factors such as vertical load, friction coefficient, tire pressure, different loads operating mode, and parameter D is change.In addition, the process of experimental test is as follows: for arranged multiple-axle vehicle, choose a steeraxle, and in the angle range of this steeraxle, get multiple corner value (such as 8 corner values respectively, i.e. α 1 to α 8) and measure the resisting moment (such as M1 to M8) corresponding when corresponding corner, thus obtain corner value corresponding to many groups and resisting moment data.By the multi-group data of mensuration is substituted into above-mentioned formula, and set vertical load, friction coefficient, tire pressure, namely obtain A, C, D, E value determined by curve, namely determine M _ijα and M _ijβ.

It is to be appreciated that the invention is not restricted to above-mentioned fitting formula and method, those skilled in the art also can adopt additive method to carry out matching M _ijα and M _ijβ.

Wherein, l _{ij α}and l _{ij β}can represent with the position of corresponding power-assisted oil cylinder respectively, i.e. l _{ij α}and l _{ij β}can be the function of the position of corresponding power-assisted oil cylinder respectively.In one embodiment of the invention, l _{ij α}=f (α _j, A _x, A _y, B _x, B _y); l _{ij β}=f (β _j, C _x, C _y, D _x, D _y), with the intersection point of the axis of i-th steeraxle and vehicle frame line of centers for the center of circle, vehicle heading is X-axis, and vehicle-width direction is in the system of axes of Y-axis, (A _x, A _y) for power-assisted oil cylinder corresponding to left wheel is when left wheel zero corner and the coordinate of the hinge A of track arm, (B _x, B _y) be the coordinate of the hinge B (not different with corner and change) of this power-assisted oil cylinder and this steeraxle, (C _x, C _y) for power-assisted oil cylinder corresponding to right wheel is when right wheel zero corner and the coordinate of the hinge C of track arm, (D _x, D _y) be the coordinate of the hinge D (not different with corner and change) of this power-assisted oil cylinder and this steeraxle.When the single wheel corner of benchmark bridge is jth value, the left wheel corner of described i-th steeraxle is α _j, now the position of hinge A forwards A' to, and the coordinate of A point becomes (A'x, A' _y); Meanwhile, the right wheel steering angle of described i-th steeraxle is β _j, now the position of hinge C forwards C' to, and the coordinate of C point becomes (C' _x, C' _y), as shown in Figure 5.

Wherein, l _{ij α}and l _{ij β}can the coordinate of two power-assisted oil cylinders be utilized express by suitable function.Such as, when the single wheel corner of benchmark bridge is jth value, described i-th steeraxle left wheel corner is α _j, now hinge A position forward A' point to, coordinate becomes (A'x, A' _y), wherein, A ' _x=A _x-[sin (φ-α _j)-sin φ] × R, A ' _y=A _y-[cos (φ-α _j)-cos φ] × R; When the single wheel corner of benchmark bridge is jth value, the right vehicle wheel rotation angle of i-th steeraxle is β _j, now the position of hinge C forwards C' point to, coordinate becomes (C' _x, C' _y), wherein, C ' _x=C _x-[sin (ψ-β _j)-sin ψ] × r, C ' _y=C _y-[cos (ψ-β _j)-cos ψ] × r, φ is the angle of steeraxle left stub earth point (the trapezoidal joint arm be connected with the power-assisted oil cylinder of left wheel and the hinge of the steeraxle) line segment that O' and A hinge is formed and Y-axis, R is the length of O'A, ψ is steeraxle right stub earth point (the trapezoidal joint arm be connected with the power-assisted oil cylinder of right wheel and the hinge of steeraxle) O " and the angle of the line segment that formed of C hinge and Y-axis, r is O " length of C;

F (α _j, A _x, A _y, B _x, B _y) represent and be a jth value and the left wheel pivot angle of described i-th steeraxle is α at the corner of the described single wheel of described benchmark bridge _jtime, left stub earth point O' to the formula of the distance of line segment A'B, i.e. arm of force computing formula now, f (β _j, C _x, C _y, D _x, D _y) represent and be a jth value and the right vehicle wheel rotation angle of described i-th steeraxle is β at the corner of the described single wheel of described benchmark bridge _jtime, right stub earth point O " to the formula of the distance of line segment C'D, i.e. arm of force computing formula now.

In plane coordinate system, can represent through this straight line formula of 2 according to two point coordinate, namely can according to the coordinate (A' of A' point _x, A' _y) and the coordinate (B of B point _x, B _y) formula of A'B place straight line can be represented.In addition, the coordinate of O' point is predetermined.Thus, the distance of an O' to line segment A'B can be tried to achieve according to the formula of the coordinate of O' point and A'B place straight line.In like manner, can in the hope of O " point is to the distance of line segment C'D.These distances obviously can with corresponding corner (i.e. α _jand β _j) and the initial coordinate (i.e. the coordinate of A, B, C, D point) of power-assisted oil cylinder represent.Particularly, l _{ij α}=f (α _j, A _x, A _y, B _x, B _y); l _{ij β}=f (β _j, C _x, C _y, D _x, D _y).Thus, the steering power square of described i-th steeraxle, the ratio of the steering power square between steering resisting torque and the steeraxle of first steeraxle, the ratio of steering resisting torque and E _ivalue can represent by the initial coordinate of corner and power-assisted oil cylinder.At specifying constraint such as A _xmin≤ A _x≤ A _xmax, A _ymin≤ A _y≤ A _ymax, B _xmin≤ B _x≤ B _xmax, B _ymin≤ B _y≤ B _ymax, C _xmin≤ C _x≤ C _xmax, C _ymin≤ C _y≤ C _ymax, D _xmin≤ D _x≤ D _xmax, D _ymin≤ D _y≤ D _ymaxwhen, can in the hope of the suitable initial coordinate of power-assisted oil cylinder to meet E _ibe worth minimum, arrange power-assisted oil cylinder according to this initial coordinate, can E be made _ibe worth minimum, thus the steering power square of this steeraxle is mated with resisting moment, reduce the stressed of steering gear connection, improve stability and the reliability of steering swivel system.It should be noted that, constraint condition can be also the parameters such as angle range, the present invention is not limited thereto.

In above-mentioned embodiment, employ plane coordinate system to represent the coordinate of power-assisted oil cylinder, but also can adopt polar coordinate system to represent.In addition, the initial point of plane coordinate system, coordinate axle also can change as required.These changes obviously all belong to scope of the present invention.

In addition, preferably, described method can comprise the power-assisted oil cylinder setting gradually each steeraxle from the head of described multi-shaft steering vehicle to afterbody.

Particularly, in one embodiment, preset the initial coordinate (i.e. the coordinate of A, B, C, D of given first steeraxle) of two power-assisted oil cylinders of first steeraxle from head to afterbody, then optimized the initial coordinate of the power-assisted oil cylinder of other steeraxles by the initial coordinate of these two power-assisted oil cylinders.That is, benchmark bridge is first bridge from head to afterbody.The left wheel steering range of first bridge to be divided into the situation of the arithmetic progression with m numerical value, particularly: when the power-assisted oil cylinder of optimization second steeraxle, i=1, target makes minimum, wherein, N _1jthe ratio of the steering power square of second steeraxle and the steering power square of first steeraxle during for being jth value at first steeraxle left wheel corner, n ₁for the now steering resisting torque of second steeraxle and the ratio of the steering resisting torque of first steeraxle.Wherein, when the left wheel corner of first steeraxle is jth value, the left wheel corner value α of second steeraxle _1jcan draw according to Acker principle.E _ivalue can be represented by the coordinate of the power-assisted oil cylinder of second steeraxle (i.e. the coordinate of A, B, C, D), by suitable coordinate, can make E _ibe worth minimum, then the initial position of the power-assisted oil cylinder of the second steeraxle is arranged according to this suitable coordinate.Wherein, the angle range of the left wheel of first steeraxle is divided into the jth numerical value in arithmetic progression that m numerical value forms by j.Then, the initial position of the power-assisted oil cylinder of the 3rd steeraxle can be optimized, i.e. i=2, n ₂be the steering power square of the 3rd steeraxle and the ratio of the steering power square of first steeraxle, n ₂it is the steering resisting torque of the 3rd steeraxle and the ratio of the steering resisting torque of first steeraxle.Selectively, after the initial coordinate of the power-assisted oil cylinder of such as second steeraxle is determined, the 3rd steeraxle can be that benchmark is optimized layout by the initial coordinate of the power-assisted oil cylinder of second steeraxle.Such as, when the power-assisted oil cylinder of optimization the 3rd steeraxle, i=1, n ₁be the steering power square of the 3rd steeraxle and the ratio of the steering power square of second steeraxle, n ₁it is the steering resisting torque of the 3rd steeraxle and the ratio of the steering resisting torque of second steeraxle.

In another embodiment, the coordinate (coordinate of A, B, C, D) of two power-assisted oil cylinders of first steeraxle can be optimized together when the power-assisted oil cylinder of optimization second steeraxle, thus determines the optimization initial coordinate of the power-assisted oil cylinder of the first steeraxle and the second steeraxle simultaneously.Wherein, the constraint condition providing first steeraxle and second steeraxle is needed.Then, identical with above-mentioned embodiment, the power-assisted oil cylinder optimizing other steeraxles can be continued.

Selectively, in the method for the invention, also can preset the initial coordinate of the power-assisted oil cylinder of any one steeraxle, or the initial coordinate of the first power-assisted oil cylinder of any two steeraxles of optimization, then optimize the power-assisted oil cylinder of other steeraxles so that E value is minimum for target.

Method of the present invention is suitable for the initial position of the power-assisted oil cylinder optimized on each steeraxle of multi-shaft steering vehicle, and the position of each steeraxle is predetermined.Such as, the position of each steeraxle can as graphic prior art, described multi-shaft steering vehicle comprises five steeraxles, the 4th bridge along direction from head to afterbody is not steeraxle, can using its vertical line as turning center line, along direction from head to afterbody, other steeraxles are respectively L1, L2, L3, L4, L5 to the distance of turning center line, thus the relation between the corner that can represent each steeraxle according to Ackerman principle.Arranging according to car load wheelbase, each steeraxle can being carried out size sequence to the distance of turning center line, as in Fig. 4 being L1 > L2 > L5 > L4 > L3.

According to a further aspect in the invention, a kind of multi-shaft steering vehicle is provided, described multi-shaft steering vehicle comprises multiple steeraxle, each steeraxle is provided with the power-assisted oil cylinder that two wheels and two are respectively used to two wheel steerings described in power-assisted, and described power-assisted oil cylinder is arranged by method according to the present invention.

In addition, in the present invention, the installation relation of the parts such as power-assisted oil cylinder, wheel, steeraxle, trapezoidal joint arm can adopt mode of the prior art, such as, connect according to the mode shown in Fig. 3.

Below by specific embodiment, method for arranging of the present invention is described.

In an embodiment of the present invention, as shown in Figure 4, multi-shaft steering vehicle comprises six bridges, wherein five is steeraxle, the 4th bridge along direction from head to afterbody be not steeraxle, using its vertical line as turning center line, and the direction of edge from head to afterbody, determined that other steeraxles are respectively L1, L2, L3, L4, L5 to the distance of turning center line, the stub ground connection spacing of steeraxle is B.

First, first steeraxle 15 preset along the direction from head to afterbody is benchmark bridge, and set its power-assisted oil cylinder in the position of initial position, namely with the intersection point of the axis of first steeraxle 15 and vehicle frame line of centers for center of circle O, vehicle heading is X-axis, vehicle-width direction is in the system of axes of Y-axis, and the hinge coordinate of two power-assisted oil cylinders of first steeraxle 15 is expressed as A ₁₅, B ₁₅, C ₁₅and D ₁₅.Particularly, setting m value, makes m the angle range of the left wheel of first steeraxle 15 can be divided into the arithmetic progression with m numerical value.By the jth of a described arithmetic progression value, suppose that now corner is α ₁₅, substitute into l _{α 15}=f (α ₁₅, A _x, A _y, B _x, B _y), l _{β 15}=f (β ₁₅, C _x, C _y, D _x, D _y), M α ₁₅=f (α ₁₅), M β ₁₅=f (β ₁₅) try to achieve first steeraxle 15 steering power square now and steering resisting torque.Wherein, β ₁₅can by the α of Ackerman principle (other steeraxles known are respectively L1, L2, L3, L4, L5 to the distance of turning center line, and the stub ground connection spacing of steeraxle is B) by correspondence ₁₅calculate.

When to optimize the power-assisted oil cylinder of second steeraxle 16 for benchmark with first steeraxle, i=1.Each j value of corresponding described arithmetic progression, the left wheel corner that can obtain the second steeraxle 16 by Ackerman principle α one to one with it ₁₆and β ₁₆, and can by the hinge coordinate A of two power-assisted oil cylinders of the second steeraxle 16 ₁₆, B ₁₆, C ₁₆and D ₁₆represent when first steeraxle 15 when left wheel turns to jth value (if now corner is α ₁₅), the steering power arm that the second steeraxle 16 is subject to and resisting moment.Thus, A can be used ₁₆, B ₁₆, C ₁₆and D ₁₆coordinate represent by providing A ₁₆, B ₁₆, C ₁₆and D ₁₆the constraint condition of coordinate, can obtain under the prerequisite meeting constraint condition and make minimum A ₁₆, B ₁₆, C ₁₆and D ₁₆coordinate figure, thus complete the optimization of initial positions of the power-assisted oil cylinder of second steeraxle 16.

Then, the initial position that above-mentioned steps continues the power-assisted oil cylinder optimizing other steeraxles can be followed.During optimization, can with first steeraxle 15 for benchmark, or with second steeraxle 16 for benchmark carries out.

Above-mentioned optimizing process can utilize suitable Optimization Software to carry out, the nonlinear function that is tied of the multivariate in MATLAB is such as utilized to minimize function f mincon, particularly, by setting design variable, restriction relation formula and setting up majorized function, then write and utilize majorized function to write concrete calculation procedure, calculate the corresponding power-assisted oil cylinder position coordinate points of acquisition and make be worth minimum.

Below the preferred embodiment of the present invention is described in detail by reference to the accompanying drawings; but; the present invention is not limited to the detail in above-mentioned embodiment; within the scope of technical conceive of the present invention; can carry out multiple simple variant to technical scheme of the present invention, these simple variant all belong to protection scope of the present invention.

It should be noted that in addition, each the concrete technical characteristic described in above-mentioned detailed description of the invention, in reconcilable situation, can be combined by any suitable mode.In order to avoid unnecessary repetition, the present invention illustrates no longer separately to various possible array mode.

In addition, also can carry out combination in any between various different embodiment of the present invention, as long as it is without prejudice to thought of the present invention, it should be considered as content disclosed in this invention equally.

Claims (9)

1. arrange the method for the power-assisted oil cylinder of multi-shaft steering vehicle for one kind, described multi-shaft steering vehicle comprises multiple steeraxle, each steeraxle is provided with the power-assisted oil cylinder that two wheels and two are respectively used to two wheel steerings described in power-assisted, and described method comprises: described power-assisted oil cylinder is arranged so that the steering power square of two of each described steeraxle corresponding power-assisted oil cylinders to this steeraxle effect and the cornering resistance match by moment of described steeraxle.

2. the method for the power-assisted oil cylinder of layout multi-shaft steering vehicle according to claim 1, wherein, described method comprises first setting benchmark bridge, and the quantity of described steeraxle is P, P be greater than 2 natural number, power-assisted oil cylinder corresponding for i-th steeraxle is arranged so that value minimum as the steering power square of described i-th steeraxle and the standard of cornering resistance match by moment, wherein, i is greater than the natural number that 1 is less than or equal to P, represents i-th steeraxle, m be greater than 0 natural number and represent the single wheel angle range of described benchmark bridge is divided into m numerical value, n _ijfor being the steering resisting torque of i-th steeraxle and the ratio of the steering resisting torque of described benchmark bridge described in during the jth in a described m numerical value value when the described single wheel corner of described benchmark bridge, N _ijfor two the power-assisted oil cylinders that are i-th steeraxle described in during the jth in a described m numerical value value when the described single wheel corner of described benchmark bridge to two power-assisted oil cylinders of the steering power square of described i-th steeraxle and described benchmark bridge to the ratio of the steering power square of described benchmark bridge.

3. the method for the power-assisted oil cylinder of layout multi-shaft steering vehicle according to claim 2, wherein, the specification of the corresponding power-assisted oil cylinder of each steeraxle is identical with operation pressure, N _ijtwo the power-assisted oil cylinders being described i-th steeraxle to two power-assisted oil cylinders of total arm of force of described i-th steeraxle and described benchmark bridge to the ratio of total arm of force of described benchmark bridge, wherein: when the corner of the described single wheel of described benchmark bridge is jth value, the total arm of force of two power-assisted oil cylinders to described i-th steeraxle of described i-th steeraxle is l _{ij α}and l _{ij β}sum, wherein, l _{ij α}for the arm of force of power-assisted oil cylinder corresponding to the left wheel of described i-th steeraxle when the corner of the described single wheel of described benchmark bridge is jth value to described i-th steeraxle, l _{ij β}for the arm of force of power-assisted oil cylinder corresponding to the right wheel of described i-th steeraxle when the corner of the described single wheel of described benchmark bridge is jth value to described i-th steeraxle; The steering resisting torque of described i-th steeraxle is M _ijα and M _ijβ sum, wherein, M _ijto be described i-th steeraxle be a jth value and the corner of the left wheel of described i-th steeraxle is α at the corner of the described single wheel of described benchmark bridge to α _jtime the resisting moment that is subject to, M _ijto be described i-th steeraxle be a jth value and the corner of the right wheel of described i-th steeraxle is β at the corner of the described single wheel of described benchmark bridge to β _jtime the resisting moment that is subject to.

4. the method for the power-assisted oil cylinder of layout multi-shaft steering vehicle according to claim 3, wherein, l _{ij α}=f (α _j, A _x, A _y, B _x, B _y); l _{ij β}=f (β _j, C _x, C _y, D _x, D _y), with the intersection point of the axis of described i-th steeraxle and vehicle frame line of centers for the center of circle, vehicle heading is X-axis, and vehicle-width direction is in the system of axes of Y-axis, (A _x, A _y) for power-assisted oil cylinder corresponding to left wheel is when left wheel zero corner and the coordinate of the hinge A of track arm, (B _x, B _y) be the coordinate of the hinge B of this power-assisted oil cylinder and this steeraxle, (C _x, C _y) for power-assisted oil cylinder corresponding to right wheel is when right wheel zero corner and the coordinate of the hinge C of track arm, (D _x, D _y) be the coordinate of the hinge D of this power-assisted oil cylinder and this steeraxle.

5. the method for the power-assisted oil cylinder of layout multi-shaft steering vehicle according to claim 4, wherein, when the corner of the described single wheel of described benchmark bridge is jth value, the left wheel pivot angle of described i-th steeraxle is α _j, now the position of hinge A forwards A' point to, coordinate becomes (A' _x, A' _y), wherein, A ' _x=A _x-[sin (φ-α _j)-sin φ] × R,

A ' _y=A _y-[cos (φ-α _j)-cos φ] × R, when the corner of the described single wheel of described benchmark bridge is jth value, the right vehicle wheel rotation angle of described i-th steeraxle is β _j, now the position of hinge C forwards C' point to, coordinate becomes (C' _x, C' _y), wherein,

C′ _x＝C _x-[sin(ψ-β _j)-sinψ]×r，

C ' _y=C _y-[cos (ψ-β _j)-cos ψ] × r, φ be the line segment that formed of steeraxle left stub earth point O' and A hinge and the angle of Y-axis, R is the length of O'A, and ψ is steeraxle right stub earth point O " and the line segment of C hinge formation and the angle of Y-axis, r is O " length of C;

F (α _j, A _x, A _y, B _x, B _y) represent and be a jth value and the left wheel pivot angle of described i-th steeraxle is α at the corner of the described single wheel of described benchmark bridge _jtime, left stub earth point O' to the formula of the distance of line segment A'B, f (β _j, C _x, C _y, D _x, D _y) represent and be a jth value and the right vehicle wheel rotation angle of described i-th steeraxle is β at the corner of the described single wheel of described benchmark bridge _jtime, right stub earth point O " to the formula of the distance of line segment C'D.

6. the method for the power-assisted oil cylinder of layout multi-shaft steering vehicle according to claim 5, wherein, A _xmin≤ A _x≤ A _xmax, A _ymin≤ A _y≤ A _ymax, B _xmin≤ B _x≤ B _xmax, B _ymin≤ B _y≤ B _ymax, C _xmin≤ C _x≤ C _xmax, C _ymin≤ C _y≤ C _ymax, D _xmin≤ D _x≤ D _xmax, D _ymin≤ D _y≤ D _ymax.

7. the method for the power-assisted oil cylinder of layout multi-shaft steering vehicle according to claim 3, wherein, described method comprises the power-assisted oil cylinder setting gradually each steeraxle from the head of described multi-shaft steering vehicle to afterbody, wherein, described benchmark bridge is the first bridge from head to afterbody, when the left wheel corner of described first bridge is jth value, the steering resisting torque of described i-th steeraxle is M _ijα and M _ijβ sum, M _ijα=f (α _j)=D × sin (C × arctan (E × α _j+ A)), M _ijβ=f (β _j)=D × sin (C × arctan (E × β _j+ A)),

M _ijα and M _ijβ is zeroaxial increasing function, and wherein, A, C, D, E are fitting parameter undetermined, and D determines the peak of curve of described increasing function; C, E determine rigidity and the shape of described curve respectively, and A determines the initial value of described curve.

8. according to the method for the power-assisted oil cylinder of the layout multi-shaft steering vehicle in claim 2-7 described in any one, wherein, described single wheel is left wheel.

9. a multi-shaft steering vehicle, described multi-shaft steering vehicle comprises multiple steeraxle, each steeraxle is provided with the power-assisted oil cylinder that two wheels and two are respectively used to two wheel steerings described in power-assisted, and described power-assisted oil cylinder is by arranging according to the method in claim 1-8 described in any one.