CN102632924B - Control strategy for sliding steering of four-wheel-hub motor driven vehicles - Google Patents

Abstract

The invention discloses a control strategy capable of realizing sliding steering in allusion to the conventional four-wheel-hub motor driven vehicles with wire controlled four-wheel steering. According to the control strategy, a sliding steering mode can be switched through a steering switch when a steering system of a vehicle is in failure, the operation space of the vehicle is limited, and the vehicle encounters a special road surface; a comprehensive electronic controller is used for judging the steering trend of the vehicle according to a corner displacement signal of a steering wheel; and output torques of four hub motors are directly controlled through a sliding steering torque distributor and then the speed difference requirements between the wheels at two sides during the steering are satisfied, so that the sliding steering with different turning radius can be realized. Through the sliding steering control strategy provided by the invention, the direction controllability of vehicles can be fully ensured on the basis of the conventional four-wheel steering.

Description

A four-wheel wheel-hub motor driven vehicle skid steer control policy

Technical field

The present invention relates to a kind of skid steer control policy, this skid steer control policy is applied in the skid steer that can realize vehicle on the four-wheel wheel-hub motor driven vehicle of line traffic control four-wheel steering.

Background technology

The In-wheel motor driving of the four-wheel wheel-hub motor driven vehicle of four-wheel steering four wheel employing same structure forms, rely on four wheel steering angles of steering swivel system change to realize and turn to, improved to a great extent low-speed maneuverability and the high-speed handing stability of automobile.The structure of conventional four-wheel steering system roughly has: mechanical type, fluid pressure type, electrodynamic type etc.Line traffic control four-wheel steering major part is to adopt four steer motor to control the deflection of four wheels.Once but the problem existing is to break down when steering swivel system, cannot make wheel deflect time, the direction of vehicle has just lost controllability; Or some Special Roads as snowfield, muddy road on four-wheel steering vehicle be difficult to control the travel direction of vehicle by changing wheel steering angle; Or will in the situation that running space is restricted, improve the manoevreability of four-wheel steering vehicle, the suspension system to vehicle and steering swivel system require very high." skid steered all terrain vehicle " (national patent, application number: CN200880122976.9) and " for thering is the power drive system of vehicle of sliding steering " (national patent, application number: CN200480031625.9) when having studied both sides wheel and deflection not occurring, the output torque of controlling both sides motor ensures that the speed between left and right sides drive wheel or crawler belt is poor, realizes skid steer.This pattern that turns to even can realize pivot stud, can improve the manoevreability of vehicle in the time that running space is restricted.Current this skid steer form only limits to be used on some special cars, such as the lunar rover vehicle, heavy tank, vehicle for construction, construction machinery and equipment or crawler-mounted snow wagon, " skid steer loader-unloader " (national patent, application number: 200380100778.X) is exactly to have introduced a kind of skid steer loader-unloader.And at present, four-wheel wheel-hub motor driven vehicle is realized the technology of skid steer and is not also appeared in the newspapers.Existing patent is mainly to have studied the vehicle structure of realizing skid steer, the control policy of skid steer is not studied.In sum, the present invention relates to a kind of skid steer control policy, this skid steer control policy is applied in the skid steer that can realize vehicle on the four-wheel wheel-hub motor driven vehicle of four-wheel steering, turn to pattern comprehensively on an automobile two kinds of four-wheel steering and skid steers, when road pavement has higher requirements, steering swivel system is switched to four-wheel steering pattern while normally work, and in the time that steering swivel system is malfunctioning, running space is restricted or run into Special Road, switches to skid steer pattern.

Summary of the invention

The object of the invention is: for the four-wheel wheel-hub motor driven vehicle of existing line traffic control four-wheel steering, when steering swivel system is malfunctioning, running space is restricted or run into the uppity problem of Special Road direction, design a kind of control policy that can realize skid steer, but do not need to add special steering hardware and extra actuating device.

Its basic thought is: integrated electronics controller is according to turning to mode switch to select the different patterns that turns to.In the time that road pavement has higher requirements, select four-wheel steering pattern, utilize steer motor to control the deflection of four wheels, realize Vehicular turn; In the time that steering swivel system is malfunctioning, running space is restricted or meet Special Road, be switched to skid steer pattern, quit work by integrated electronics controller control steer motor, and according to driver information, directly control the output torque of both sides motor by skid steer torque divider, ensure to have certain torque differences between the wheel of both sides, meet the poor requirement of speed between the wheel of both sides while turning to, thereby realize the skid steer of different turn radiuss.In the time of both sides wheel velocity equal and opposite in direction, opposite direction, can realize no-radius turns to.These two kinds turn to pattern by turning to mode switch to switch, fully ensure the direction controllability of automobile.

Realize technical scheme of the present invention as follows:

Integrated electronics controller, according to steering wheel angle displacement signal, judges that vehicle is turn left or turn right, taking vehicle right hand steering as example; Integrated electronics controller judges that according to acceleration pedal displacement signal and brake pedal displacement signal vehicle is accelerate or slow down, taking vehicle acceleration as example; T _in, T _outthe inside and outside both sides of representative wheel hub motor is always exported torque, T respectively ₁, T ₃and n ₁, n ₃represent respectively the output torque and rotational speed of front and back, left side two wheel hub motors, T ₂, T ₄and n ₂, n ₄represent respectively the output torque and rotational speed of front and back, right side two wheel hub motors.Define the positive and negative of torque: if the variation tendency direction of Torque and speed or rotating speed is consistent, this torque is positive torque so, is driving torque; In like manner, if the variation tendency opposite direction of Torque and speed or rotating speed, this torque, for negative torque, is braking torque so.

According to skid steer control principle drawing as shown in Figure 1, chaufeur is by turning to mode switch to select skid steer pattern ' 1 ', and by integrated electronics controller, steering swivel system is quit work, and control the output torque that distributes four wheel hub motors, realize the skid steer of vehicle.Acceleration pedal displacement pickup expects that by vehicle tach signal sends into integrated electronics controller, steering wheel angle displacement pickup is sent expectation Turning radius signal into integrated electronics controller, and integrated electronics controller calculates respectively the now inside and outside required total torque value T of both sides motor according to skid steer control policy _in, T _out, and give respectively two wheel hub electric machine controller input torque signal T before and after inner side _in/ 2, give respectively outside two wheel hub electric machine controller input torque signal T _out/ 2, export respectively torque T thereby control four wheel hub motors ₁=T _out/ 2, T ₂=T _in/ 2, T ₃=T _out/ 2, T ₄=T _in/ 2, make to occur certain torque differences between the wheel of automobile both sides, utilize this torque differences to realize the skid steer of different turn radiuss.

Figure 2 shows that the steering wheel angle displacement input that the present invention defines.θ ₁, θ ₂, θ ₃be respectively three steering wheel angle displacement critical values of definition, when | θ | at three different interval (0, θ of the skid steer torque divider shown in Fig. 3 ₁), (θ ₁, θ ₂), (θ ₂, θ ₃) time, torque, the rotary speed property difference of the output of inside and outside both sides motor.

The output torque of acceleration pedal, brake pedal displacement and motor is linear, when chaufeur bend the throttle, and motor output drive strength, direction is identical with motor speed direction; When chaufeur is stepped on brake pedal, motor output braking force, direction and motor speed opposite direction.T _maxit is the maximum output torque of four wheel hub motors.

Acceleration pedal displacement signal control coefficient A:

$A=\frac{\mathrm{\α}-{\mathrm{\α}}_0}{{\mathrm{\α}}_{\max }-{\mathrm{\α}}_0}$

In formula, α is acceleration pedal displacement, α ₀for accelerator free travel displacement, α _maxfor the range displacement of acceleration pedal.The span of A is [0,1], and its corresponding single motor output torque is [0, T so _max].

Brake pedal displacement signal control coefficient B:

$B=-\frac{\mathrm{\β}-{\mathrm{\β}}_0}{{\mathrm{\β}}_{\max }-{\mathrm{\β}}_0}$

In formula, β is brake pedal displacement, β ₀for brake pedal free stroke displacement, β _maxfor the range displacement of brake pedal.The span of B is [1,0], and its corresponding single motor output torque is [T so _max, 0].

Steering wheel angle displacement signal control coefficient x:

$x=\left\{\begin{array}{cc}0& 0\&le;\left|\mathrm{\&theta;}\right|\&le;{\mathrm{\&theta;}}_1\\ 1-\frac{\mathrm{\&theta;}-{\mathrm{\&theta;}}_1}{{\mathrm{\&theta;}}_2-{\mathrm{\&theta;}}_1}& {\mathrm{\&theta;}}_1<\left|\mathrm{\&theta;}\right|\&le;{\mathrm{\&theta;}}_2\\ -\frac{\mathrm{\&theta;}-{\mathrm{\&theta;}}_2}{{\mathrm{\&theta;}}_3-{\mathrm{\&theta;}}_2}& {\mathrm{\&theta;}}_2\left|\mathrm{\&theta;}\right|\&le;{\mathrm{\&theta;}}_3\end{array}\right.$

Further, utilization of the present invention skid steer torque divider as shown in Figure 3, by integrated electronics controller according to steering wheel angle displacement signal, acceleration pedal displacement signal, electronic gear on-off signal, to total output torque T of inside and outside both sides wheel hub motor _inwith T _outdistribute control.

As 0< θ≤θ ₁time, vehicle straight, the inside and outside both sides of now integrated electronics controller control wheel hub motor is exported total driving torque T _in=2AT _max, T _out=2AT _max, now T _inwith T _outpass be: T _in=T _out, the torque value of four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=AT _max;

Work as θ ₁< θ < θ ₂time, wheel hub motor is exported total driving torque T outside the control of integrated electronics controller _out=2AT _max, make outside motor produce driving torque, control inner side wheel hub motor simultaneously and export total driving torque T _in=2xAT _max, make inner side motor produce driving torque, now T _inwith T _outpass be: T _in<T _out, ensure the torque differences of inside and outside both sides motor, to realize skid steer, the torque value of four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=xAT _max;

As θ=θ ₂time, wheel hub motor is exported total driving torque T outside the control of integrated electronics controller _out=2AT _max, make outside motor produce driving torque, control inner side wheel hub motor simultaneously and export total driving torque T _in=0, now inboard wheel velocity reversal is consistent with outside wheel speed direction, and the torque value of four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=0;

Work as θ ₂< θ < θ ₃time, wheel hub motor is exported total driving torque T outside the control of integrated electronics controller _out=2AT _max, make outside motor produce driving torque, control inner side wheel hub motor output total braking force square T simultaneously _in=-2xAT _max, make inner side motor produce braking torque, now inboard wheel velocity reversal is consistent with outside wheel speed direction, and the torque value of four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=-xAT _max;

As θ=θ ₃time, wheel hub motor is exported total driving torque T outside the control of integrated electronics controller _out=2AT _max, make outside motor produce driving torque, control inner side wheel hub motor output lock torque T simultaneously _in=-2xAT _max, make inner side motor produce braking torque, inner side motor speed n _inthe torque value of=0, four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=-xAT _max;

In like manner, still taking vehicle right-hand rotation as example, in the time that chaufeur is stepped on brake pedal, show that vehicle will reduce speed now; Integrated electronics controller is according to steering wheel angle displacement signal and brake pedal displacement signal, utilize brake pedal displacement signal control coefficient B and steering wheel angle displacement signal control coefficient x, by outside two-wheeled hub motor output total torque T in the control of skid steer torque divider _in=2BT _max, T _out=2xBT _max, export respectively torque value T by four wheel hub motors of four hub motor control devices control ₁=T ₃=xBT _max, T ₂=T ₄=BT _max, ensure to have certain torque differences between the wheel of both sides, meet the poor requirement of speed between the wheel of both sides while turning to, thereby realize the skid steer of different turn radiuss.

Beneficial effect

Skid steer control policy is applied on the four-wheel wheel-hub motor driven vehicle of line traffic control four-wheel steering can ensure vehicle steering capability in all cases.In the good situation of driving conditions, select four-wheel steering mode of operation well to realize the turning efficiency of vehicle; Turn to space to be restricted steering swivel system is malfunctioning or the severe pavement conditions such as ice and snow under, select skid steer pattern, control the directivity of vehicle.These the two kinds controllabilitys that turn to the mutual switching of pattern can fully ensure vehicle heading.

Brief description of the drawings

Fig. 1 is skid steer control principle drawing of the present invention

Fig. 2 is steering wheel angle displacement input

Fig. 3 is skid steer torque divider constructional drawing of the present invention

Fig. 4 is the vehicle structure schematic diagram with skid steer pattern of the present invention

Detailed description of the invention

Below in conjunction with the drawings and specific embodiments, the present invention is further illustrated.

This skid steer control policy is to realize on a line traffic control four-wheel steering four-wheel wheel-hub motor driven vehicle structure platform as shown in Figure 4, this vehicle structure adopts four identical wheel hub motor direct drive of wheels, by bearing circle and corner displacement sensor 1 thereof, acceleration pedal and displacement pickup 2 thereof, brake pedal and displacement pickup 3 thereof, electronic gear switch 4, turn to mode switch 5, energy management unit 6, energy absorbing device 7, hub motor control device 8a, hub motor control device 8b, hub motor control device 8c, hub motor control device 8d, steer motor controller 9a, steer motor controller 9b, steer motor controller 9c, steer motor controller 9d, steer motor 10a, steer motor 10b, steer motor 10c, steer motor 10d, wheel hub motor 11a, wheel hub motor 11b, wheel hub motor 11c, wheel hub motor 11d, battery pack 12, integrated electronics controller 13 forms.Wherein, integrated electronics controller 13 is respectively by CAN bus node 1, CAN bus node 2, CAN bus node 3, CAN bus node 4, CAN bus node 5, CAN bus node 6, CAN bus node 7, CAN bus node 8, CAN bus node 9, CAN bus node 10, CAN bus node 11 and hub motor control device 8d, steer motor controller 9d, hub motor control device 8c, battery management unit 12, steer motor controller 9c, hub motor control device 8b, energy management unit 6, steer motor controller 9b, hub motor control device 8a, energy absorbing device 7, steer motor controller 9a is connected.Control four wheel deflections by steer motor 10a, steer motor 10b, steer motor 10c, steer motor 10d.

Skid steer mode of operation: defined three steering wheel angle critical value θ ₁, θ ₂, θ ₃, integrated electronics controller 13 bases steering wheel angle displacement input as shown in Figure 2, judges that vehicle is turn left or turn right, taking vehicle right hand steering as example; Judge that according to acceleration pedal displacement and brake pedal displacement signal vehicle is accelerate or slow down, taking vehicle acceleration as example;

Acceleration pedal displacement pickup 2 expects that by vehicle rotating speed sends into integrated electronics controller 13, expectation Turning radius is passed to integrated electronics controller 13 by steering wheel angle displacement pickup 1, integrated electronics controller 13, according to steering wheel angle displacement signal skid steer torque divider as shown in Figure 3, calculates respectively the now inside and outside required total torque value T of both sides motor _in, T _out, give two wheel hub electric machine controller 8a, hub motor control device 8b input torque signal T before and after inner side _in/ 2, give outside two wheel hub electric machine controller 8c, hub motor control device 8d input torque signal T _out/ 2.

This skid steer control policy is realized on four-wheel wheel-hub motor driven vehicle as shown in Figure 4.θ ₁=5 °, θ ₂=20 °, θ ₃=45 °, α ₀=6mm, α _max=60mm, β ₀=6mm, β _max=60mm, the maximum output torque of four wheel hub motors is T _max=145Nm.

In the time of θ=3 °, α=30mm, β=0mm, integrated electronics controller 13 obtains steering wheel angle displacement signal by steering wheel angle displacement pickup 1, judges 0< θ < θ ₁, now A=1/2, B=0, x=0, skid steer torque divider is to T _in, T _outcontrol distribution, T _in=T _out=2AT _max=145Nm.Integrated electronics controller 13 is given hub motor control device 8a, hub motor control device 8b, hub motor control device 8c, hub motor control device 8d input torque signal 72.5Nm by CAN node 9, CAN node 6, CAN node 3, CAN node 1 respectively, all exports 72.5Nm thereby control wheel hub motor 11a, wheel hub motor 11b, wheel hub motor 11c, wheel hub motor 11d.

In the time of θ=10 °, α=25mm, β=0mm, integrated electronics controller 13 obtains steering wheel angle displacement signal by steering wheel angle displacement pickup 1, judges θ ₁< θ < θ ₂, now A=5/12, B=0, x=2/3, skid steer torque divider is to T _in, T _outcontrol distribution, T _in=2xAT _max=80.56Nm, T _out=2AT _max=120.8Nm, integrated electronics controller 13 is given hub motor control device 8a, hub motor control device 8b, hub motor control device 8c, hub motor control device 8d input torque signal T by CAN node 9, CAN node 6, CAN node 3, CAN node 1 respectively ₂=T ₄=2xAT _max/ 2=40.28Nm, T ₁=T ₃=2AT _max/ 2=60.4Nm, all exports 40.28Nm thereby control wheel hub motor 11a, wheel hub motor 11b, and wheel hub motor 11c, wheel hub motor 11d all export 60.4Nm;

In the time of θ=-20 °, α=20mm, β=0mm, integrated electronics controller 13 obtains steering wheel angle displacement signal by steering wheel angle displacement pickup 1, judges θ=θ ₂, now A=1/3, B=0, x=0, skid steer torque divider is to T _in, T _outcontrol distribution, T _in=2xAT _max=0Nm, T _out=22AT _max=96.67Nm, integrated electronics controller 13 is given hub motor control device 8a, hub motor control device 8b, hub motor control device 8c, hub motor control device 8d input torque signal T by CAN node 9, CAN node 6, CAN node 3, CAN node 1 respectively ₂=T ₄=2xAT _max/ 2=0Nm, T ₁=T ₃=2AT _max/ 2=48.3Nm, all exports 0Nm thereby control wheel hub motor 11a, wheel hub motor 11b, and wheel hub motor 11c, wheel hub motor 11d all export 48.3Nm;

In the time of θ=30 °, α=18mm, β=0mm, integrated electronics controller 13 obtains steering wheel angle displacement signal by steering wheel angle displacement pickup 1, judges θ ₂< θ < θ ₃, now A=3/10, B=0, x=-2/5, skid steer torque divider is to T _in, T _outcontrol distribution, T _in=2xAT _max=-34.8Nm, T _out=2AT _max=87Nm, integrated electronics controller 13 is given hub motor control device 8a, hub motor control device 8b, hub motor control device 8c, hub motor control device 8d input torque signal T by CAN node 9, CAN node 6, CAN node 3, CAN node 1 respectively ₂=T ₄=2xAT _max/ 2=-17.4Nm, T ₁=T ₃=2AT _max/ 2=21.75Nm, thus wheel hub motor 11a, all export-17.4Nm of wheel hub motor 11b controlled, and wheel hub motor 11c, wheel hub motor 11d all export 43.5Nm;

In the time of θ=45 °, α=15mm, β=0mm, integrated electronics controller 13 obtains steering wheel angle displacement signal by steering wheel angle displacement pickup 1, judges θ=θ ₃, now A=1/4, B=0, x=-1, skid steer torque divider is to T _in, T _outcontrol distribution, T _in=2xAT _max-72.5Nm, T _out=2AT _max=72.5Nm, integrated electronics controller 13 is given hub motor control device 8a, hub motor control device 8b, hub motor control device 8c, hub motor control device 8d input torque signal T by CAN node 9, CAN node 6, CAN node 3, CAN node 1 respectively ₂=T ₄=2xAT _max/ 2=-36.25Nm controls n simultaneously ₂=n ₄=0, T ₁=T ₃=2AT _max/ 2=36.25Nm, thus wheel hub motor 11a, all export-36.25Nm of wheel hub motor 11b controlled, and wheel hub motor 11c, wheel hub motor 11d all export 36.25Nm.

Claims (2)

1. the skid steer control policy based on four-wheel wheel-hub motor driven vehicle, it is characterized in that: this skid steer control policy is applied in the skid steer of realizing vehicle on the four-wheel wheel-hub motor driven vehicle of line traffic control four-wheel steering, it turns to pattern comprehensively to an automobile two kinds of four-wheel steering and skid steers, turning to space to be restricted, under the malfunctioning or ice and snow road condition of steering swivel system, select skid steer pattern to control the directivity of vehicle: integrated electronics controller turns to pattern according to turning to mode switch to switch described two kinds, in the time that having higher requirements, road pavement selects four-wheel steering pattern, utilize steering system to control the deflection of four wheels, realize Vehicular turn, in the time that steering swivel system is malfunctioning, running space is restricted or meet Special Road, be switched to skid steer pattern, do not work by integrated electronics controller control steering swivel system, and according to steering wheel angle displacement signal, acceleration pedal displacement signal, electronic gear on-off signal, directly control total output torque of inside and outside both sides wheel hub motor by skid steer torque divider, ensure to have torque differences between the wheel of both sides, meet the poor requirement of speed between the wheel of both sides while turning to, thereby realize the skid steer of different turn radiuss, in the time of both sides wheel velocity equal and opposite in direction, opposite direction, realizing no-radius turns to.

2. the skid steer control policy based on four-wheel wheel-hub motor driven vehicle according to claim 1, is characterized in that: defined three steering wheel angle displacement critical value θ ₁, θ ₂, θ ₃, when | θ | in three different interval (0, θ ₁), (θ ₁, θ ₂), (θ ₂, θ ₃) time, torque, the rotary speed property difference of the output of inside and outside both sides motor, corresponding turn inside diameter radius is also different; The output torque of acceleration pedal, brake pedal displacement and motor is linear, when chaufeur bend the throttle, and motor output drive strength, direction is identical with motor speed direction; When chaufeur is stepped on brake pedal, motor output braking force, direction and motor speed opposite direction; T _maxfor the maximum output torque of single wheel hub motor; T ₁, T ₃and n ₁, n ₃represent respectively the output torque and rotational speed of front and back, left side two wheel hub motors; T ₂, T ₄and n ₂, n ₄represent respectively the output torque and rotational speed of front and back, right side two wheel hub motors;

Acceleration pedal displacement signal control coefficient A:

$A=\frac{\mathrm{\&alpha;}-{\mathrm{\&alpha;}}_0}{{\mathrm{\&alpha;}}_{\max }-{\mathrm{\&alpha;}}_0}$

In formula, α is acceleration pedal displacement, α ₀for accelerator free travel displacement, α _maxfor the range displacement of acceleration pedal, the span of A is [0,1], and its corresponding single motor output torque is [0, T _max];

Brake pedal displacement signal control coefficient B:

$B=-\frac{\mathrm{\&beta;}-{\mathrm{\&beta;}}_0}{{\mathrm{\&beta;}}_{\max }-{\mathrm{\&beta;}}_0}$

In formula, β is brake pedal displacement, β ₀for brake pedal free stroke displacement, β _maxfor the range displacement of brake pedal, the span of B is [1,0], and its corresponding single motor output torque is [T _max, 0];

Steering wheel angle displacement signal control coefficient x:

$x=\left\{\begin{array}{cc}0& 0\&le;\left|\mathrm{\&theta;}\right|\&le;{\mathrm{\&theta;}}_1\\ 1-\frac{\mathrm{\&theta;}-{\mathrm{\&theta;}}_1}{{\mathrm{\&theta;}}_2-{\mathrm{\&theta;}}_1}& {\mathrm{\&theta;}}_1<\left|\mathrm{\&theta;}\right|\&le;{\mathrm{\&theta;}}_2\\ -\frac{\mathrm{\&theta;}-{\mathrm{\&theta;}}_2}{{\mathrm{\&theta;}}_3-{\mathrm{\&theta;}}_2}& {\mathrm{\&theta;}}_2<\left|\mathrm{\&theta;}\right|\&le;{\mathrm{\&theta;}}_3\end{array}\right.$

Utilize skid steer torque divider, by integrated electronics controller according to steering wheel angle displacement signal control coefficient x, acceleration pedal displacement signal control coefficient A, electronic gear on-off signal, to total output torque T of inside and outside both sides wheel hub motor _inwith T _outdistribute control, first define the positive and negative of torque: if the variation tendency direction of Torque and speed or rotating speed is consistent, this torque is positive torque, is driving torque; If the variation tendency opposite direction of Torque and speed or rotating speed, this torque, for negative torque, is braking torque;

When vehicle is turned right, right motor is inner side motor; When chaufeur bend the throttle, and 0≤θ≤θ ₁time, judge vehicle straight; As θ > θ ₁time, judge vehicle right-hand rotation;

As 0≤θ≤θ ₁time, the inside and outside both sides of integrated electronics controller control wheel hub motor is exported total driving torque T _in=2AT _max, T _out=2AT _max, now T _inwith T _outpass be: T _in=T _out, the torque value of four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=AT _max;

Work as θ ₁< θ < θ ₂time, wheel hub motor is exported total driving torque T outside the control of integrated electronics controller _out=2AT _max, make outside motor produce driving torque, control inner side wheel hub motor simultaneously and export total driving torque T _in=2xAT _max, make inner side motor produce driving torque, now T _inwith T _outpass be: T _in< T _out, ensure the torque differences of inside and outside both sides motor, to realize skid steer, the torque value of four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=xAT _max;

As θ=θ ₂time, wheel hub motor is exported total driving torque T outside the control of integrated electronics controller _out=2AT _max, make outside motor produce driving torque, control inner side wheel hub motor simultaneously and export total driving torque T _in=0, now inboard wheel velocity reversal is consistent with outside wheel speed direction, and the torque value of four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=0;

Work as θ ₂< θ < θ ₃time, wheel hub motor is exported total driving torque T outside the control of integrated electronics controller _out=2AT _max, make outside motor produce driving torque, control inner side wheel hub motor output total braking force square T simultaneously _in=-2xAT _max, make inner side motor produce braking torque, now inboard wheel velocity reversal is consistent with outside wheel speed direction, and the torque value of four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=-xAT _max;

As θ=θ ₃time, wheel hub motor is exported total driving torque T outside the control of integrated electronics controller _out=2AT _max, make outside motor produce driving torque, control inner side wheel hub motor output lock torque T simultaneously _in=-2xAT _max, make inner side motor produce braking torque, inner side motor speed n _inthe torque value of=0, four wheel hub motor outputs is respectively T ₁=T ₃=AT _max, T ₂=T ₄=-xAT _max;

In the time that chaufeur is stepped on brake pedal, show that vehicle will reduce speed now; Integrated electronics controller is according to steering wheel angle displacement signal and brake pedal displacement signal, utilize brake pedal displacement signal control coefficient B and steering wheel angle displacement signal control coefficient x, by outside two-wheeled hub motor output total torque T in the control of skid steer torque divider _in=2BT _max, T _out=2xBT _max, export respectively torque value T by four wheel hub motors of four hub motor control devices control ₁=T ₃=xBT _max, T ₂=T ₄=BT _max, ensure to have torque differences between the wheel of both sides, meet the poor requirement of speed between the wheel of both sides while turning to, thereby realize the skid steer of different turn radiuss.