CN102591332B - Device and method for local path planning of pilotless automobile - Google Patents

Abstract

The invention relates to a device and a method for local path planning of a pilotless automobile. The device comprises an environment sensing device, a repulsion force calculating device, a gravitation force calculating device, a resultant force direction angle calculating device and a steering wheel turning angle calculating device, wherein the environment sensing device is used for detecting obstacles and building a road boundary model and a road center line model, the repulsion force calculating device is used for building a repulsion force point function and calculating the repulsion force, the gravitation force calculating device is used for building a gravitation force point function and calculating the gravitation force, the resultant force direction angle calculating device Is used for calculating the resultant force direction angle of the repulsion force and the gravitation force, and the steering wheel turning angle calculating device is used for determining the steering wheel turning angle according to the direction angle of the resultant force and the transmission ratio of a steering system. The method has the advantages that the problems of path oscillation and minimum sunk local part because the repulsion force and the gravitation force are in the same direction in a manual potential field method are eliminated, and in addition, the running path deflection of vehicles caused by uncertain factors can be corrected in real time.

Description

Device and method for intelligent car local paths planning

Technical field

The invention belongs to intelligent vehicle technical field, be specifically related to the device and method for driverless operation local paths planning.

Background technology

Intelligent car system (Autonomous Ground Vehicle is called for short AGV) is a kind ofly according to various sensors, to obtain environmental informations and vehicle-state, position, by the understanding of environment being controlled automatically to the intelligent control system of vehicular drive behavior, mainly by sensor, treater, the installation compositions such as controller.

Local paths planning is one of gordian technique of intelligent car research.Local paths planning refers to: intelligent car is in uncertain road environment, and target that will reach that information, the global path planning that control system provides according to environment sensing system and vehicle-state checking system provides etc. is cooked up the current driving path of vehicle in real time.

Artificial Potential Field Method is comparative maturity and the good planing method of real-time in local paths planning research, it is that the environmental information of Vehicle Driving Cycle is abstract in gravitational field function and repulsion field function, by composite force field function cook up one from initial point to gravitation the collisionless path of point (object point).

Summary of the invention

The object of the present invention is to provide a kind of device and method for intelligent car local paths planning, it is in the situation that not needing to set up complex environment model, calculates the driving path of intelligent car according to environmental characteristic.

For reaching above object, solution of the present invention is:

For a device for intelligent car local paths planning, it comprises:

Environmental perception device, for detecting obstacles thing, sets up road boundary model and road-center line model;

Repulsion computer device, for setting up repulsion point function and calculating repulsion;

Gravitation computer device, for setting up gravitation point function and calculating gravitation;

Resultant direction angle calculation device, for calculating the orientation angle of making a concerted effort of repulsion and gravitation;

Steering wheel angle computer device, orientation angle and the steering swivel system transmitting ratio directions dish corner of for basis, making a concerted effort.

Further, described environmental perception device is vision sensor and radar, vision sensor is surveyed road boundary and is calculated road axis, radar detection obstacle information, the path coordinate dot information that vision sensor is provided fits to repeatedly curve, sets up road boundary model and road-center line model.

Described environmental perception device is radar, radar detection curb, and matching road boundary information, extrapolates road axis information, sets up road boundary model and road-center line model.

The real time information of the environment that described repulsion computer device provides according to environmental perception device determines that the border, two road that vehicle will travel sets up repulsion point function; And according to repulsion point function, calculate the change along with environment, the position of automatic driving car repulsion point and the calculating repulsion point repulsion size to intelligent car.

Described gravitation computer device calculates the transverse distance take between the road axis of road axis that new boundary line is road and current vehicle place road by deviation computer device, by Gauss, being subordinate to composite function will have the information of clear, obstacle distance intelligent car distance to be reflected in real time on gravitation point function simultaneously in road; And calculate the change along with environment according to gravitation point function, the position of automatic driving car gravitation point, and calculate the gravitation size of gravitation point to intelligent car.

For a method for intelligent car local paths planning, it comprises:

Environment sensing step, detecting obstacles thing, sets up road boundary model and road-center line model;

Repulsion calculation procedure, sets up repulsion point function and calculates repulsion;

Gravitation calculation procedure, sets up gravitation point function and calculates gravitation;

Resultant direction angle calculation step, the orientation angle of making a concerted effort of calculating repulsion and gravitation;

Steering wheel angle calculation procedure, according to the orientation angle of making a concerted effort and steering swivel system transmitting ratio directions dish corner.

Further, described environment sensing step is that vision sensor is surveyed road boundary and calculates road axis, radar detection obstacle information, the path coordinate dot information that vision sensor is provided fits to repeatedly curve, sets up road boundary model and road-center line model.

Described environment sensing step is radar detection curb, and matching road boundary information, extrapolates road axis information, sets up road boundary model and road-center line model.

The real time information of the environment that described repulsion calculation procedure provides according to environmental perception device determines that the border, two road that vehicle will travel sets up repulsion point function; And according to repulsion point function, calculate the change along with environment, the position of automatic driving car repulsion point and the calculating repulsion point repulsion size to intelligent car.

Described gravitation calculation procedure is calculated the transverse distance take between the road axis of road axis that new boundary line is road and current vehicle place road by deviation computer device, by Gauss, being subordinate to composite function will have the information of clear, obstacle distance intelligent car distance to be reflected in real time on gravitation point function simultaneously in road; And calculate the change along with environment according to gravitation point function, the position of automatic driving car gravitation point, and calculate the gravitation size of gravitation point to intelligent car.

Owing to having adopted such scheme, the present invention has following characteristics:

1), by utilizing Gauss to combine the method for subordinate function real-time response environmental change, the invention solves in Traditional Man potential field method the problem that is absorbed in local minimum and path concussion producing when the same direction due to repulsion and gravitation;

2) by the selection of repulsion point function, when vehicle departs from target line and sails path because being subject to such as side direction wind, road roughness etc. of interference of uncertain factor, repulsion and gravitation with joint efforts guided vehicle is got back to target driving path, improved the robust performance of vehicle tracking dreamboat driving path;

3) owing to not needing to set up complex environment model, only need constructing environment characteristic model to realize local paths planning, therefore required sensor data information amount requires real-time less, processing data information better, contribute to reduce sensor cost on the one hand, be also conducive to meet on the other hand the requirement of the high real-time responsiveness of vehicle control syetem;

4) the present invention has good compatible with environment, in embodiment of the present invention, lift two kinds of running environments, the present invention, for other running environments, stops up but has such as four corners and can pass through path situation etc., can realize vehicle automatic obstacle-avoiding under multiple environment;

5) by Gauss, combine the setting of subordinate function coefficient, the target path function that travels also can meet vehicle minimum turning radius, vehicle kinematics and dynamic (dynamical) constraint conditions such as front-wheel steering locking angle speed, make controlled object can be good at following the tracks of the expected path providing, thereby realize the optimal control of expection.

Accompanying drawing explanation

Fig. 1 is local paths planning device schematic diagram.

Fig. 2 is environmental characteristic model apparatus for establishing schematic diagram.

Fig. 3 is gravitation point function apparatus for establishing schematic diagram.

Fig. 4 is the track of vehicle comparison diagram that σ gets different value.

Fig. 5 is resultant direction angle calculation device schematic diagram.

Fig. 6 is automatic driving car driving trace simulation result figure under clear environment.

Fig. 7 is automatic driving car expectation steering wheel angle figure under clear environment.

Fig. 8 is automatic driving car driving trace simulation result figure under obstacle environment.

Fig. 9 is automatic driving car expectation steering wheel angle figure under obstacle environment.

The specific embodiment

Below in conjunction with accompanying drawing illustrated embodiment, the present invention is further illustrated.

The present invention is on the basis of Artificial Potential Field APF (Artificial Potential Field) method, utilize Gauss to combine subordinate function and set up the target path function that travels, it is the gravitation point function of Artificial Potential Field Method, the variation real-time embodying of environment, in the variation of gravitation point function, and is calculated to gravitation with this; According to obstacle information and road edge information, obtain repulsion point function, with this, calculate repulsion.By gravitation and repulsion, calculate the suffered resultant direction of intelligent car again, thereby cook up automatic driving car by the path of travelling.When vehicle travels along target driving path, two repulsion are cancelled each other, and gravitation plays a leading role, once vehicle is because the interference that is subject to uncertain factor side direction wind for example, roads roughness etc. depart from target line and sail path, repulsion and gravitation with joint efforts guided vehicle is got back to target driving path.

A kind of device calculating for gravitation in the present invention, comprise gravitation point function apparatus for establishing and gravitation computer device, wherein this gravitation point function device comprises: deviation is calculated, for calculating the transverse distance of take between the road axis of road axis that new boundary line is road and current vehicle place road; By Gauss, being subordinate to composite function will have clear, obstacle distance intelligent car distance etc. to be reflected in real time on gravitation point function in road; Wherein this gravitation computer device clicks and fetches calculating gravitation according to gravitation on gravitation point function.

Wherein, this deviation computer device obtains according to radar (laser or millimeter wave radar) obstacles borders dot information and road-center line computation.

Wherein, this gravitation point function provides road axis according to vision system, according to the variation of real time environment, by the maximum change calculations that solves road axis deviation and the occur value that deviates, and utilize Gauss to be subordinate to the information of composite function real-time embodying obstacle, thereby obtain gravitation point function.

Wherein, the coefficient that this Gauss is subordinate to composite function will make target driving path meet the kinematic and dynamic constraints condition of vehicle.

Wherein, this gravitation point is chosen and will be determined according to the speed of the curvature of road and vehicle.

The device calculating for repulsion, comprises repulsion point function apparatus for establishing and repulsion computer device, and the real time information of the environment that wherein repulsion point function provides according to vision sensor and radar determines that the border, two road that vehicle will travel sets up; Repulsion computer device is for calculating repulsion size according to repulsion point.

The present invention also comprises and by making a concerted effort, is converted into steering wheel angle device, comprise the steps: to establish bodywork reference frame, according to gravitation size and the direction under bodywork reference frame, gravitation is decomposed into the component of orthogonal axis, according to repulsion size and the direction under bodywork reference frame, repulsion is decomposed into the component of orthogonal axis, thereby calculate front wheel angle, then go out steering wheel angle according to steering swivel system gear ratio calculation.

The present invention intends using vision sensor survey road boundary and calculate road axis, use radar (laser or millimeter wave radar) detecting obstacles thing information, the path coordinate dot information that vision system is provided fits to repeatedly curve and (considers the Dynamic Constraints of vehicle, one is three times and usings upper curve) set up road boundary model and road-center line model (also can be only with laser radar as environment sensing system, utilize laser radar detection curb, matching road boundary information, extrapolates road axis information).Based on sensor, obtain environmental characteristic model, Gauss in gravitation point function is subordinate to composite function item by the variation of environment in real-time embodying road, the distance that whether occurs obstacle, obstacle and driverless operation workshop, and calculate gravitation according to the gravitation point function obtaining in real time; According to environment change, set up repulsion point function, and calculate repulsion size according to repulsion point function.Local paths planning device schematic diagram is as Fig. 1.

1, environment sensing:

According to vision system, on bodywork reference frame, set up boundary's function model on both sides of the road

$\left\{\begin{array}{c}{y}_1=a_1{x}^3+b_1{x}^2+c_{1}x+d_1\\ y_2=a_1{x}^3+b_1{x}^2+c_{1}x+d_2\end{array}\right.---\left(1\right)$

A wherein ₁, b ₁, c ₁, d ₁, d ₂for cubic curve coefficient.

By formula (1), release road axis function model

y _centre＝a ₁x ³+b ₁x ²+c ₁x+(d ₁+d ₂)/2 (2)

While having obstacle in road, the Road information data providing by radar scanning and vision system merges, and obtains the real-time coordinate (X of the most dangerous boundary point of obstacle under the same coordinate system in current road _ob, Y _ob), obtain the data message on two borders that can be by road.By above original data, obtain the key model of environmental characteristic.Environmental characteristic model apparatus for establishing schematic diagram is as Fig. 2.

2, gravitation point function is set up

Vehicle travels on structured road, must there is road boundary constraint, and may there is obstacle, exist the situation of obstacle to there are two kinds of possibilities, be that obstacle and road boundary are the widest by a path during as boundary line, a kind of is that two obstacles are the widest path of passing through during as border.Gravitation point function apparatus for establishing is as Fig. 3.

1) in road, there is no obstacle

Now, the constraint that vehicle is subject to boundary line, two road can not drive to beyond road, and therefore, two lane boundary line are repulsion point function, and gravitation point function is road-center line function.

2) while having obstacle in road

While having obstacle in road, first select the widest road passing through, thereby determine road boundary point and deviation ratio.

In road, there is the gravitation point function in the situation of obstacle, be divided into two kinds of situations, a kind of situation obstacle is as a side boundary line, lane boundary line is as opposite side boundary line, be that repulsion point function is respectively lane boundary line and the most dangerous boundary point of obstacle, another kind of situation be two obstacles as boundary line, now with the first situation, described in detail.

Repulsion point function is the real-time coordinate points (X of lane boundary line and obstacle most dangerous point in this case _ob, Y _ob).

Obstacle and on one side Road form and can produce new road axis by the border in path, the required maximum offset of original path line of centers function

Δs＝|(a ₁x _ob ³+b ₁x _ob ²+c ₁x _ob+(d ₁+d ₂)/2)-(y _ob+a ₂x _ob ³+b ₂x _ob ²+c ₂x _ob+d ₂)/2| (3)

The gravitation point function under the edge-restraint condition of vehicle in being obstacles borders is on one side

y _goal＝a ₁x ³+b ₁x ²+c ₁x+(d ₁+d ₂)/2+Δs (4)

But directly add a side-play amount, can cause the discontinuous of path curvature, not meet the kinematical constraint condition of vehicle, to sum up analyze and consider vehicle constraint condition, adopt smooth excessive two objective functions of Gauss member function, therefore revise gravitation point function and be

y _goal＝a ₁x ³+b ₁x ²+c ₁x+(d ₁+d ₂)/2+Δs*exp(-(X-X _ob) ²/2*σ ²) (5)

Wherein σ is the coefficient relevant to the bent curvature of a curve of Gauss member function, in the gravitation point function of gravitation, by the Dynamic Constraints that regulates its value can meet vehicle, is path curvature bounded and path curvature bounded reciprocal, as Fig. 4 σ gets the path locus of different value.The situation that as seen from the above analysis there is no obstacle in road is the special case that has obstacle situation in road, i.e. Δ s*exp ((X-X in the situation that there is no obstacle _ob) ²/ 2* σ ²to go to zero.

To sum up, establishing gravitation point function is

y _goal＝a ₁x ³+b ₁x ²+c ₁x+(d ₁+d ₂)/2+Δs*exp(-(X-X _ob) ²/2*σ ²) (6)

3, repulsion point function is set up

Repulsion point function

1), when there is no obstacle, it is formula (1) that repulsion point function is road boundary

2), while having obstacle in road, according to the widest, by road boundary situation, will introduce obstacle as a lateral boundaries

4, gravitation calculates

In the method intelligent car (controlled object) is reduced to a particle, its space, place is two-dimentional theorem in Euclid space.The position X=[xy of controlled object in space] ^t, in the present invention, because be under bodywork reference frame, so X=[00] ^t.Controlled object is at the suffered gravitational field function U of X _att(X) be defined as and target location X _g=[x _gy _g] ^trelevant function:

$U_{\mathrm{att}}\left(X\right)=\frac{1}{2}\mathrm{\κ}{(X-X_g)}^2---\left(7\right)$

In formula: κ is gravitational field gain.Corresponding gravitation F _att(X) be the negative gradient of gravitational field:

$F_{\mathrm{att}}\left(X\right)=-\▿U_{\mathrm{att}}\left(X\right)=-\mathrm{\κ}{\mathrm{\ρ}}_g{a}_G---\left(8\right)$

In formula: a _gfor the targeted unit vector of controlled object; ρ _g=|| X-X _g|| be the distance between controlled object and gravitation point.

5, repulsion calculates

Repulsion field function is

$U_{\mathrm{rep}}\left(X\right)=\left\{\begin{array}{cc}\frac{1}{2}\mathrm{\η}{(\frac{1}{{\mathrm{\ρ}}_{\mathrm{ob}}}-\frac{1}{{\mathrm{\ρ}}_0})}^2{{\mathrm{\ρ}}_g}^n& {\mathrm{\ρ}}_{\mathrm{ob}}\≤{\mathrm{\ρ}}_0\\ 0& {\mathrm{\ρ}}_{\mathrm{ob}}>{\mathrm{\ρ}}_0\end{array}\right.---\left(9\right)$

In formula, n is one and is greater than any real number of zero.

When controlled object is not during at gravitation point, corresponding repulsion is:

$F_{\mathrm{rep}}\left(X\right)=\left\{\begin{array}{cc}(F_{\mathrm{rep}1}+F_{\mathrm{rep}2})a_o& {\mathrm{\ρ}}_{\mathrm{ob}}\≤{\mathrm{\ρ}}_0\\ 0& {\mathrm{\ρ}}_{\mathrm{ob}}>{\mathrm{\ρ}}_0\end{array}\right.---\left(10\right)$

Wherein:

$F_{\mathrm{rep}1}=\mathrm{\η}(\frac{1}{{\mathrm{\ρ}}_{\mathrm{ob}}}-\frac{1}{{\mathrm{\ρ}}_0})\frac{{{\mathrm{\ρ}}_g}^n}{{{\mathrm{\ρ}}_{\mathrm{ob}}}^2}$

$F_{\mathrm{rep}2}=\frac{n}{2}\mathrm{\η}{(\frac{1}{{\mathrm{\ρ}}_{\mathrm{ob}}}-\frac{1}{{\mathrm{\ρ}}_0})}^2{{\mathrm{\ρ}}_g}^{n-1}$

In formula: η is the gain of repulsion field function, ρ _ob=|| X-X _ob|| be the shortest distance of controlled object and obstacle, constant ρ ₀the distance that affects for the obstacle set according to the speed of a motor vehicle.

A wherein _ounit vector for obstacle sensing controlled object.

6, resultant direction is calculated

Resultant direction has determined the sense of motion of controlled object.Under bodywork reference frame, gravitation and repulsion are decomposed into respectively to the component on two coordinate axlees.Resultant direction angle calculation device schematic diagram is as Fig. 5.

Take bodywork reference frame on the gravitation point function that coordinate axle is set up, choose gravitation point X _g=[x _g, y _g], the angle between automatic driving car and gravitation point

α＝arctan(y _g/x _g) (11)

The component of gravitation on horizontal stroke, ordinate is

$\left\{\begin{array}{c}{F}_{\mathrm{att}}\left(x_g\right)=F_{\mathrm{att}}*\cos \left(\mathrm{\α}\right)\\ F_{\mathrm{att}}\left(y_g\right)=F_{\mathrm{att}}*\sin \left(\mathrm{\α}\right)\end{array}\right.---\left(12\right)$

On bodywork reference frame, repulsion point X _ob(i)=[x _ob(i), y _ob(i)], the angle between automatic driving car and obstacle

β _i＝arctan(y _ob(i)/x _ob(i)) (13)

The component of repulsion on horizontal stroke, ordinate is

$\left\{\begin{array}{c}{F}_{\mathrm{rep}}\left(x_{\mathrm{ob}}\left(i\right)\right)=F_{\mathrm{rep}}\left(i\right)*\cos \left({\mathrm{\β}}_i\right)\\ F_{\mathrm{rep}}\left(y_{\mathrm{ob}}\left(i\right)\right)=F_{\mathrm{rep}}\left(i\right)*\sin \left({\mathrm{\β}}_i\right)\end{array}\right.---\left(14\right)$

Intelligent car and the angle of making a concerted effort, the i.e. course angle of expectation

θ＝arctan((F _att(y)+F _rep(y(i)))/(F _att(x)+F _rep(x(i)))) (15)

Steering wheel angle

δ _sw＝θ*i _s (16)

I wherein _sfor steering swivel system transmitting ratio.

Above invention is carried out under varying environment to simulating, verifying, each parameter of system adopts following value:

κ=6, ρ ₀=10, η=0.7, n=2, σ=4.5, speed of a motor vehicle v=18km/h

In road, clear or obstacle (are ρ not within the scope of active distance _ob> ρ ₀), utilize improvement Artificial Potential Field Method to using lane boundary line as repulsion, using road axis as gravitation, now correction term is zero.Fig. 6 is intelligent car driving trace, from driving trace, can find out, intelligent car can be good at following road axis.Fig. 7 is steering wheel angle, from the steering wheel angle order providing, can find out, expectation corner smooth and meet vehicle kinematic and dynamic constraints (for example, turned to actuating unit to limit, being constrained to of the steering wheel angle of intelligent car | δ _sw| <=500 °, being constrained to of steering wheel angle speed | V _δ| <=200 °/s.As can be seen from Figure 7, under clear environment, while utilizing automatic driving vehicle of the present invention to travel in having the road of certain curvature, steering wheel angle can remain in 200 degree, and steering wheel angle speed also can remain in the restriction range of 200 degree/seconds).

In road ahead, there is obstacle, and automatic driving car and obstacle distance (ρ in efficient range _ob≤ ρ ₀), using obstacle and a side lane boundary line as repulsion point function, now correction term is relevant with maximum offset, and the line of centers of obstacles borders line and lane boundary line of take is gravitation.Fig. 8 is intelligent car driving trace, from driving trace, can find out, and while having obstacle in road, the cut-through thing that intelligent car can be level and smooth, and after cut-through thing, the level and smooth road axis of getting back to.Fig. 9 is steering wheel angle, from the steering wheel angle providing, can find out, expectation corner is smooth and meet vehicle dynamics constraint and (having under obstacle environment, utilize steering wheel angle of the present invention can remain in 120 degree, steering wheel angle speed also can remain in the restriction range of 200 degree/seconds).

The description of above-described embodiment is can understand and apply the invention for ease of those skilled in the art.Person skilled in the art obviously can easily make various modifications to these embodiment, and one application of principle described herein in other embodiment and needn't pass through performing creative labour.Therefore, the invention is not restricted to the embodiment here, those skilled in the art are according to announcement of the present invention, and the improvement of making for the present invention and modification all should be within protection scope of the present invention.

Claims (6)

1. for a device for intelligent car local paths planning, it is characterized in that: it comprises:

Environmental perception device, for detecting obstacles thing, sets up road boundary model and road-center line model;

Repulsion computer device, for setting up repulsion point function and calculating repulsion;

Gravitation computer device, for setting up gravitation point function and calculating gravitation;

Resultant direction angle calculation device, for calculating the orientation angle of making a concerted effort of repulsion and gravitation;

Steering wheel angle computer device, orientation angle and the steering swivel system transmitting ratio directions dish corner of for basis, making a concerted effort;

The real time information of the environment that described repulsion computer device provides according to environmental perception device determines that the border, two road that vehicle will travel sets up repulsion point function; And according to repulsion point function, calculate the change along with environment, the position of intelligent car repulsion point and the calculating repulsion point repulsion size to intelligent car;

Described gravitation computer device calculates the transverse distance take between the road axis of road axis that new boundary line is road and current vehicle place road by deviation computer device, by Gauss, being subordinate to composite function will have the information of clear, obstacle distance intelligent car distance to be reflected in real time on gravitation point function simultaneously in road; And calculate the change along with environment according to gravitation point function, the position of intelligent car gravitation point, and calculate the gravitation size of gravitation point to intelligent car.

2. the device for intelligent car local paths planning as claimed in claim 1, it is characterized in that: described environmental perception device is vision sensor and radar, vision sensor is surveyed road boundary and is calculated road axis, radar detection obstacle information, the path coordinate dot information that vision sensor is provided fits to repeatedly curve, sets up road boundary model and road-center line model.

3. the device for intelligent car local paths planning as claimed in claim 1, it is characterized in that: described environmental perception device is radar radar detection curb, matching road boundary information, extrapolate road axis information, set up road boundary model and road-center line model.

4. for a method for intelligent car local paths planning, it is characterized in that: it comprises:

Environment sensing step, detecting obstacles thing, sets up road boundary model and road-center line model;

Repulsion calculation procedure, sets up repulsion point function and calculates repulsion;

Gravitation calculation procedure, sets up gravitation point function and calculates gravitation;

Resultant direction angle calculation step, the orientation angle of making a concerted effort of calculating repulsion and gravitation;

Steering wheel angle calculation procedure, according to the orientation angle of making a concerted effort and steering swivel system transmitting ratio directions dish corner;

The real time information of the environment that described repulsion calculation procedure provides according to environmental perception device determines that the border, two road that vehicle will travel sets up repulsion point function; And according to repulsion point function, calculate the change along with environment, the position of intelligent car repulsion point and the calculating repulsion point repulsion size to intelligent car;

Described gravitation calculation procedure is calculated the transverse distance take between the road axis of road axis that new boundary line is road and current vehicle place road by deviation computer device, by Gauss, being subordinate to composite function will have the information of clear, obstacle distance intelligent car distance to be reflected in real time on gravitation point function simultaneously in road; And calculate the change along with environment according to gravitation point function, the position of intelligent car gravitation point, and calculate the gravitation size of gravitation point to intelligent car.

5. the method for intelligent car local paths planning as claimed in claim 4, it is characterized in that: described environment sensing step is that vision sensor is surveyed road boundary and calculates road axis, radar detection obstacle information, the path coordinate dot information that vision sensor is provided fits to repeatedly curve, sets up road boundary model and road-center line model.

6. the method for intelligent car local paths planning as claimed in claim 4, it is characterized in that: described environment sensing step is radar detection curb, matching road boundary information, extrapolates road axis information, sets up road boundary model and road-center line model.