Automobile cornering rollover prevention control system and control method therefor

Abstract

An automobile cornering rollover prevention control system includes a controller, four hydraulic oil cylinders, a deflection measuring instrument and a rotation speed measuring instrument. The controller is mounted inside the automobile, and includes a data acquisition module, a data processing module and a data execution module, wherein the data acquisition module and the data execution module are connected to the data processing module, an input end of the data acquisition module is electrically connected to the deflection measuring instrument and the rotation speed measuring instrument, and an output end of the data execution module is connected to control ends of the four hydraulic oil cylinders respectively. The deflection measuring instrument and the rotation speed measuring instrument are mounted on a left front wheel of the automobile, and two hydraulic oil cylinders are mounted between an automobile frame and a front axle, and the other two hydraulic oil cylinders are mounted between the automobile frame and a rear axle.

Claims

1. An automobile cornering rollover prevention control system comprising: a controller; four hydraulic oil cylinders; a deflection measuring instrument; and a rotation speed measuring instrument, wherein the controller is mounted inside an automobile, and comprises a data acquisition module, a data processing module, and a data execution module, both the data acquisition module and the data execution module are electrically connected to the data processing module, an input end of the data acquisition module is electrically connected to the deflection measuring instrument and the rotation speed measuring instrument respectively, and an output end of the data execution module is electrically connected to control inputs of the four hydraulic oil cylinders respectively, wherein the deflection measuring instrument is mounted on a left front wheel of the automobile, the rotation speed measuring instrument is mounted on the left front wheel of the automobile, two of the four hydraulic oil cylinders are respectively mounted to and positioned between an automobile frame and a front axle, and the other two of the four hydraulic oil cylinders are mounted to and positioned between the automobile frame and a rear axle, and the four hydraulic oil cylinders are disposed pairwise and symmetrically, two initiation airbags are arranged between and connected to the automobile frame and the front axle, two initiation airbags are also arranged between and connected to the automobile frame and the rear axle, and control inputs of the four initiation airbags are all electrically connected to the data execution module, wherein the deflection measuring instrument is a wheel deflection measuring instrument that monitors automobile declination and gathers a deflection angle .sub.L of the automobile during instantaneous cornering, the rotation speed measuring instrument is an instrument that monitors a rotation speed of a wheel and gathers a speed .sub.L of the automobile during movement, and the controller calculates a position change a of a center of gravity G at the speed .sub.L of the automobile so as to compare the change with a safe position change threshold of the center of gravity G at the speed .sub.L of the automobile, control the four hydraulic oil cylinders to move, promote an automobile body to be lifted for a certain distance h in the opposite direction to the position change a of the center of gravity G, wherein the controller is an electronic control unit, wherein all the hydraulic oil cylinders are provided with a grating ruler for measuring an extending distance of the corresponding hydraulic oil cylinder, and an output end of the grating ruler is electrically connected to the data acquisition module, wherein the controller is configured to perform: step I, manually setting existing parameters that comprise a wheel base B and an axle base L, the center of gravity G of the automobile body, and the safe position change threshold of the center of gravity G, the center of gravity G of the automobile body being composed of half wheel base data a and half axle base data b; step II, obtaining, via the wheel deflection measuring instrument, the deflection angle .sub.L of the wheel and obtaining, via the rotation speed measuring instrument, the speed .sub.L of a left front wheel by the automobile cornering rollover prevention control system during cornering, calculating, by the controller, according to a following formula: ${}_2=\frac{{}_1}{2}-{\tan }^{-1}\left(\frac{B\text{/}2-a}{h_1}\right),r_L=\frac{L}{\sin \left({}_L\right)},{}_{G^{}}=\{\begin{array}{cc}{\tan }^{-1}\left(\frac{L-b}{r_L\cos \left({}_L\right)-\left(a+a\right)+B}\right)& \mathrm{turn}\mathrm{left}\\ {\tan }^{-1}\left(\frac{L-b}{r_L\cos \left({}_L\right)+\left(a+a\right)-B}\right)& \mathrm{turn}\mathrm{right}\end{array},a=2\sqrt{h_1^2+{\left(B\text{/}2-a\right)}^2}\sin \left({}_1\text{/}2\right)\cos \left({}_2\right),h_1=a\tan \left(.Math.{}_2.Math.\right),r_{G^{}}=\frac{L-b}{\sin \left({}_{G^{}}\right)},$ wherein .sub.1 is an included angle between a connecting line of an ascending section and a descending section of two front or rear hydraulic oil cylinders and a horizontal line; wherein .sub.2 is an included angle between a connecting line of the positions of the center of gravity before and after the change of the center of gravity and the horizontal line; wherein h.sub.1 is a distance between the position of the center of gravity G before the change of the center of gravity and the sections of the two front hydraulic cylinders; and wherein .sub.G is an included angle between a connecting line of the position of the center of gravity G after the change and an instantaneous speed center O, which is a point coincident with the front axle or the rear axle, a speed .sub.G and a centripetal force F.sub.G at the center of gravity G of the automobile: $v_{G^{}}=\frac{r_{G^{}}}{r_L}{v}_L,F_{G^{}}=m\frac{v_{G^{}}^2}{r_{G^{}}},$ calculating a centripetal force moment (T.sub.G) in an axle direction of the automobile according to the data above, which is:
T.sub.G(.sub.1)=F.sub.G(h.sub.1+h.sub.2h.sub.1)cos(.sub.G) wherein when the automobile rolls over during concerning, an inside wheel leaves a ground and a rollover torque of the automobile at the moment is: $T_{\mathrm{Gravity}}\left({}_1\right)=\{\begin{array}{cc}\mathrm{mg}\left(a+a\right)& \mathrm{turn}\mathrm{left}\\ \mathrm{mg}\left[B-\left(a+a\right)\right]& \mathrm{turn}\mathrm{right}\end{array},$ based on an equilibrium of forces equation:
T.sub.G(.sub.1)=T.sub.Gravity(.sub.1); and obtaining a critical lifted distance h.sub.Critical:
h.sub.Critical=c tan(.sub.1), wherein c is a distance between a mounting position of the hydraulic cylinder and an axis of symmetry of the automobile; and step III, executing actions based on the critical lifted distance h.sub.Critical, which is calculated in step II, wherein the actions include the data processing module controlling expansion links of the four hydraulic oil cylinders to extend according to an output result of the data processing module of a at the speed .sub.L, so that a lifted distance h of the four hydraulic oil cylinders of the automobile body in opposition to a value of the position change of the center of gravity G is larger than the critical lifted distance h.sub.Critical, wherein r.sub.g, is a distance from the instantaneous speed center O to the position of the center of gravity G after the change in center of gravity, wherein r.sub.L is a distance from the instantaneous speed center O to left front wheel of the automobile, wherein m is a mass of the automobile, wherein q is an acceleration of gravity, wherein c is one-half of the wheel base B.

2. The automobile cornering rollover prevention control system according to claim 1, wherein the expansion links of the four hydraulic oil cylinders are fed back by the grating ruler in real time, and the expansion links of the four hydraulic oil cylinders are adjusted by the controller in real time.

3. The automobile cornering rollover prevention control system according to claim 2, wherein if the lifted distance h of the four hydraulic oil cylinders of the automobile body in opposition to the value of the position change of the center of gravity G is smaller than the critical lifted distance h.sub.Critical, then the controller sends a control signal to an instrument panel, wherein the action further includes the instrument panel flashing for alarming and the initiation airbags initiating.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a module diagram of an automobile cornering rollover prevention control method according to the present invention;

(2) FIG. 2 is a structure diagram of an automobile having a cornering rollover prevention system according to the present invention;

(3) FIG. 3 is a front view of the automobile having the cornering rollover prevention system according to the present invention;

(4) FIG. 4 is a block diagram of the automobile illustrated in FIG. 3 when turning left;

(5) FIG. 5 is a partial enlarged diagram of a hydraulic oil cylinder portion of the automobile when turning left according to the present invention;

(6) FIG. 6 is a partial enlarged diagram of a position change of a centre of gravity of an automobile body when the automobile according to the present invention turns left;

(7) FIG. 7 is a simplified mechanics analysis diagram of the automobile with a deflection measuring instrument and a rotation speed measuring instrument mounted on a left front wheel when turning left; and

(8) FIG. 8 is a simplified mechanics analysis diagram of the automobile with a deflection measuring instrument and a rotation speed measuring instrument mounted on a right front wheel when turning left,

(9) In the figures: 1 refers to left rear wheel; 2 refers to left front wheel; 3 refers to right rear wheel; and 4 refers to right front wheel.

DETAILED DESCRIPTION

(10) The technical solutions of the present invention are further described in details hereunder with reference to the specific embodiments and drawings.

Embodiment 1

(11) An automobile cornering rollover prevention control system (refer to FIG. 1 to FIG. 8) powered up by an automobile power supply includes a controller, four hydraulic oil cylinders, a deflection measuring instrument and a rotation speed measuring instrument, wherein the controller is mounted inside the automobile, and includes a data acquisition module, a data processing module and a data execution module, both the data acquisition module and the data execution module are electrically connected to the data processing module, an input end of the data acquisition module is electrically connected to the deflection measuring instrument and the rotation speed measuring instrument respectively, and an output end of the data execution module is connected to control ends of the four hydraulic oil cylinders respectively; the deflection measuring instrument is mounted on a left front wheel of the automobile, the rotation speed measuring instrument is mounted on the left front wheel of the automobile, two of the four hydraulic oil cylinders are respectively mounted between an automobile frame and a front axle, and the other two of the four hydraulic oil cylinders are mounted between the automobile frame and a rear axle; and the four hydraulic oil cylinders are disposed pairwise and symmetrically. Two initiation airbags are arranged between the automobile frame and the front axle, two initiation airbags are also arranged between the automobile frame and the rear axle, and control ends of the four initiation airbags are all electrically connected to the data execution module. The wheel deflection measuring instrument is a wheel deflection measuring instrument that monitors automobile declination and induces a deflection angle of the automobile during instantaneous cornering, the rotation speed measuring instrument is a rotation speed measuring instrument that monitors a rotation speed of a wheel and induces a speed of the automobile during marching, and the controller is a controller that calculates a position change of a centre of gravity at a current speed of the automobile so as to compare the change with a safe position change threshold of the centre of gravity G at the speed of the automobile, control the hydraulic oil cylinders to move, promote an automobile body to be lifted for a certain distance reversely to the position change of the centre of gravity, and guarantee the safe driving of the automobile. The controller is an ECU. All the hydraulic oil cylinders are provided with a grating ruler for measuring an extending distance of the hydraulic oil cylinder, and an output end of the grating ruler is electrically connected to the data acquisition module.

(12) An automobile cornering rollover prevention control method applicable to the automobile cornering rollover prevention control system above includes the following steps of:

(13) step I, manually setting existing parameters that includes a wheel base and an axle base, a standard centre of gravity of an automobile body, and a safe position change threshold of the centre of gravity, the standard centre of gravity of the automobile body being composed of half wheel base data and half axle base data;
step II, obtaining a deflection angle of the wheel and a speed of a left front wheel by the automobile cornering rollover prevention control system during cornering, wherein .sub.1 is an included angle between a connecting line of an ascending section and a descending section of two front or rear hydraulic oil cylinders and a horizontal line; .sub.2 is an included angle between a connecting line of the positions of the centre of gravity before and after the change of the centre of gravity and the horizontal line; h.sub.1 is a distance between the position of the centre of gravity before the change of the centre of gravity and the sections of the two front hydraulic cylinders; and .sub.G is an included angle between a connecting line of the position of the centre of gravity G after the change and an instantaneous speed centre O, and a wheel axle, a speed .sub.G and a centripetal force F.sub.G at the centre of gravity of the automobile:

(14) $v_{G^{}}=\frac{r_{G^{}}}{r_L}{v}_L,F_{G^{}}=m\frac{v_{G^{}}^2}{r_{G^{}}},$
calculating a centripetal force moment in an axle direction of the automobile according to the data above, which is
T.sub.G(.sub.1)=F.sub.G(h.sub.1+h.sub.2h.sub.1)cos(.sub.G)
wherein when the automobile rolls over during concerning, an inside wheel leaves the ground; and a rollover torque of the automobile at the moment is

(15) $T_{\mathrm{Gravity}}\left({}_1\right)=\{\begin{array}{cc}\mathrm{mg}\left(a+a\right)& \mathrm{turn}\mathrm{left}\\ \mathrm{mg}\left[B-\left(a+a\right)\right]& \mathrm{turn}\mathrm{right}\end{array},$
being concluded from equilibrium of forces:
T.sub.G(.sub.1)=T.sub.Gravity(.sub.1)
and finally obtaining a critical lifted distance h.sub.Critical
h.sub.Critical=c tan(.sub.1)
and c is a distance between a mounting position of the hydraulic cylinder and an axis of symmetry of the automobile; and

(16) step III, executing actions, wherein a data processing module controls expansion links of four hydraulic oil cylinders to extend according to an output result of the data processing module, so that the lifted distance h of the hydraulic oil cylinders of the automobile body reversely to a value of a position change of the centre of gravity is larger than a theoretically critical lifted distance h.sub.Critical.

(17) The content above is explained by taking the left wheel as an example, and if the right wheel is taken an example, then a following formula:

(18) $r_L=\frac{L}{\sin \left({}_L\right)},{}_{G^{}}=\{\begin{array}{cc}{\tan }^{-1}\left(\frac{L-b}{r_L\cos \left({}_L\right)-\left(a+a\right)-B}\right)& \mathrm{turn}\mathrm{left}\\ {\tan }^{-1}\left(\frac{L-b}{r_L\cos \left({}_L\right)+\left(a+a\right)-B}\right)& \mathrm{turn}\mathrm{right}\end{array},v_{G^{}}=\frac{r_{G^{}}}{r_L}{v}_L$
needs to be amended into:

(19) $r_R=\frac{L}{\sin \left({}_R\right)},{}_{G^{}}=\{\begin{array}{cc}{\tan }^{-1}\left(\frac{L-b}{r_R\cos \left({}_R\right)-\left(a+a\right)}\right)& \mathrm{turn}\mathrm{left}\\ {\tan }^{-1}\left(\frac{L-b}{r_R\cos \left({}_R\right)+\left(a+a\right)}\right)& \mathrm{turn}\mathrm{right}\end{array},v_{G^{}}=\frac{r_{G^{}}}{r_R}{v}_R.$

(20) Such an alternation may be understood and implemented by those skilled in the art with reference to the present application; moreover, the rotation speed measuring instrument and the deflection measuring instrument may also be mounted on different wheels, and the rotation speed measuring instrument may also be mounted on the rear wheel in meanwhile, which shall also fall within the protection scope of the present application.

(21) The expansion links of the four hydraulic oil cylinders are fed back by the grating rulers in real time, and the expansion links of the four hydraulic oil cylinders are finely adjusted by the controller in real time.

(22) If the lifted distance h of the hydraulic oil cylinders of the automobile body reversely to the value of the position change of the centre of gravity is smaller than the critical lifted distance h.sub.Critical, then the controller sends a control signal to an instrument panel, and the instrument panel flashes for alarming, and the initiation airbags are initiated.

(23) The embodiment above is merely a preferred solution of the present invention, and is not intended to limit the present invention in any way. Other amendments and modifications without departing from the technical solution recorded in the claims may also be made.