Automatic driving method and device able to diagnose decisions

Abstract

An automatic driving method and device able to diagnose decisions is disclosed herein, wherein a vehicle body signal sensor detects vehicle body information, and an environment sensor detects traffic environment information. The information is transmitted to a central processor to generate a future driving track. The central processor examines whether the differences between the future driving track and the traffic environment information and the indexes of the future driving track meet tolerances. If no, the central processor transmits notification information to an automatic driving controller. If yes, the central processor transmits the future driving track to the automatic driving controller to make the automatic driving controller undertake automatic driving according to the future driving track. The present invention can automatically judge whether the future driving track generated by the central processor is within tolerances and determine whether the automatic driving track is safe.

Claims

1. An automatic driving method able to diagnose decisions, comprising steps: receiving vehicle body information of a present vehicle associated with operational characteristics of said vehicle and traffic environment information associated with external environment parameters and parameters associated with interaction with an external object; generating a future driving track of said present vehicle according to said vehicle body information; and introducing said future driving track and said traffic environment information into a diagnostic equation to determine whether difference values of said future driving track, difference values of said traffic environment information, and associated indexes of said future driving track and said traffic environment information meet respective tolerances, if said tolerances are not met, transmitting notification information to an automatic driving controller; if said tolerances are met, transmitting said future driving track to said automatic driving controller to enable said automatic driving controller to undertake automatic driving according to said future driving track; wherein said diagnostic equation is a logarithm of a function of indicator functions to examine whether a curvature difference between a future driving curvature of said future driving track and lane marker curvature information of said traffic environment information, a neighboring vehicle distance index of said future driving track, a lateral slide displacement index of said future driving track, a vehicle turnover index of said future driving track, a difference of distances to left and right lane markers, a forward collision time index of said future driving track, and a rear collision time index of said future driving track respectively meet a tolerance of curvature, a tolerance of distance to a neighboring vehicle; a tolerance of lateral slide displacement, a tolerance of turnover, a tolerance of difference of distances to left and right lane makers, a tolerance of forward collision time, and a tolerance of rear collision time; wherein the said diagnostic equation using different prime numbers greater than 1 as representative numerals to recognize represented events, each represented event associated with a corresponding indicator function, whereby each indicator function includes a tolerance value for determination of the contribution of the prime number associated with each event in the diagnostic equation.

2. The automatic driving method able to diagnose decisions according to claim 1, wherein said diagnostic equation generates a non-zero deviation value before said step of transmitting said notification information to said automatic driving controller, and generates a zero deviation value before said step of transmitting said future driving track to said automatic driving controller.

3. The automatic driving method able to diagnose decisions according to claim 1, wherein said vehicle body information includes present vehicle steering wheel angular velocity information; present vehicle speed information; present vehicle acceleration-deceleration information, and present vehicle coordinate information; said traffic environment information is image information; lane marker curvature information, distance to another vehicle information, left lane marker position information, right lane marker position information, and another vehicle speed information is worked out according to said image information.

4. The automatic driving method able to diagnose decisions according to claim 3, wherein said difference of distances to left and right lane markers is a difference between a distance between said present vehicle position information of said vehicle body information and said left lane marker position information of said traffic environment information and a distance between said present vehicle position information of said vehicle body information and said right lane marker position information of said traffic environment information.

5. The automatic driving method able to diagnose decisions according to claim 3, wherein said diagnostic equation is expressed by $L=\log \left\{\underset{t=1}{\overset{n}{.Math.}}\left[\frac{\begin{array}{c}{2}^{\underset{t=1}{\overset{2}{.Math.}}I\left(.Math.K_H\left(x_t\right)-K_i\left(x_t\right).Math.\ge {\mathrm{.Math.}}_K\right)}{3}^{I\left(D-V/2\le 0\right)}\\ 7^{I\left(a_H{J}_H/{\mathrm{SR}}_H\ge {\mathrm{.Math.}}_A\right)}{13}^{I\left(\mathrm{LTR}\ge {\mathrm{.Math.}}_L\right)}\end{array}}{\begin{array}{c}{5}^{I\left(.Math.D_L\left(x_t,y_t\right)-D_R\left(x_t,y_t\right).Math.\ge {\mathrm{.Math.}}_D\right)}\\ {11}^{I\left(\mathrm{do}\mathrm{LG}\right)\left[I\left({\mathrm{TTC}}_H\left(\mathrm{Forward}\right)\le {\mathrm{.Math.}}_F\right).Math.I\left({\mathrm{TTC}}_R\left(\mathrm{Host}\right)\le {\mathrm{.Math.}}_R\right)\right]}\end{array}}\right]\right\}$ wherein L is a deviation value; I() is said indicator function; K.sub.H(x.sub.t) is said future driving curvature at said present vehicle coordinate information x.sub.t; K.sub.i(x.sub.t) is said lane marker curvature information at said present vehicle coordinate information x.sub.t; ε.sub.K is said tolerance of curvature; D is said distance to another vehicle information; V is said present vehicle speed information; a.sub.H is said present vehicle acceleration-deceleration information; J.sub.H is present vehicle jerk information; SR.sub.H is said present vehicle steering wheel angular velocity information; (a.sub.HJ.sub.H/SR.sub.H) is the equation for calculating lateral slide displacement index; ε.sub.A is said tolerance of lateral slide displacement; LTR is said vehicle turnover index; ε.sub.L is said tolerance of turnover; D.sub.L(x.sub.t,y.sub.t) is said distance between said present vehicle coordinate information x.sub.t,y.sub.t and said left lane marker position information; D.sub.R(x.sub.t,y.sub.t) is said distance between said present vehicle coordinate information x.sub.t,y.sub.t and said right lane marker position information; ε.sub.D is said tolerance of difference of distances to left and right lane markers; TTC.sub.H(Forward) is said forward collision time index; ε.sub.F is said tolerance of forward collision time; TTC.sub.R(Host) is said rear collision time index; ε.sub.R is said tolerance of rear collision time; 2, 3, 5, 7, 11, and 13 are said representative numerals respectively representing different events; do LG(do lane change) is an event that said present vehicle changes lanes.

6. The automatic driving method able to diagnose decisions according to claim 1, wherein after said step of transmitting said notification information to said automatic driving controller, said automatic driving controller interrupts automatic driving according to said notification information.

7. The automatic driving method able to diagnose decisions according to claim 1, wherein after said step of transmitting said notification information to said automatic driving controller, said future driving track is modified to generate a new future driving track and make said curvature difference, said neighboring vehicle distance index, said lateral slide displacement index, said vehicle turnover index, said difference of distances to left and right lane markers, said forward collision time index, and said rear collision time index respectively meet said tolerance of curvature, said tolerance of distance to a neighboring vehicle; said tolerance of lateral slide displacement, said tolerance of turnover, said tolerance of difference of distances to left and right lane makers, said tolerance of forward collision time, and said tolerance of rear collision time, and wherein said new future driving track is transmitted to said automatic driving controller to enable said automatic driving controller to undertake automatic driving according to said new future driving track.

8. An automatic driving device able to diagnose decisions, comprising: at least one vehicle body signal sensor detecting a present vehicle to generate vehicle body information associated with operational characteristics of said vehicle; at least one environment sensor detecting external environment to generate traffic environment information associated with external environment parameters and parameters associated with interaction with an external object; a central processor electrically connected with said vehicle body signal sensor and said environment sensor, generating a future driving track according to said vehicle body information, and introducing said future driving track and said traffic environment information into a diagnostic equation, wherein if difference values between said future driving track, difference values between said traffic environment information, and associated indexes of said future driving track and said traffic environment information do not meet tolerances, said central processor sends out notification information, and wherein if said difference values between said future driving track, and said difference values between said traffic environment information, and said associated indexes of said future driving track and said traffic environment information meet said tolerances, said central processor directly sends out said future driving track; and an automatic driving controller electrically connected with said central processor and receiving said notification information or said future driving track, wherein if said automatic driving controller receives said future driving track, said automatic driving track undertakes automatic driving according to said future driving track; wherein said diagnostic equation is a logarithm of a function of indicator functions to examine whether a curvature difference between a future driving curvature of said future driving track and lane marker curvature information of said traffic environment information, a neighboring vehicle distance index of said future driving track, a lateral slide displacement index of said future driving track, a vehicle turnover index of said future driving track, a difference of distances to left and right lane markers, a forward collision time index of said future driving track, and a rear collision time index of said future driving track respectively meet a tolerance of curvature, a tolerance of distance to a neighboring vehicle; a tolerance of lateral slide displacement, a tolerance of turnover, a tolerance of difference of distances to left and right lane makers, a tolerance of forward collision time, and a tolerance of rear collision time; wherein the said diagnostic equation using different prime numbers greater than 1 as representative numerals to recognize represented events, each represented event associated with a corresponding indicator function, whereby each indicator function includes a tolerance value for determination of the contribution of the prime number associated with each event in the diagnostic equation.

9. The automatic driving device able to diagnose decisions according to claim 8, wherein said diagnostic equation generates a non-zero deviation value before transmitting said notification information to said automatic driving controller, and generates a zero deviation value before transmitting said future driving track to said automatic driving controller.

10. The automatic driving device able to diagnose decisions according to claim 8, wherein said at least one vehicle body signal sensor includes a steering wheel angular velocity sensor, a vehicle speed sensor, and a position sensor, which respectively detect present vehicle steering wheel angular velocity information, present vehicle speed information, present vehicle acceleration-deceleration information, and present vehicle coordinate information.

11. The automatic driving device able to diagnose decisions according to claim 10, wherein said environment sensor is an image sensor generating image information; said lane marker curvature information, said distance to another vehicle information, said left lane marker position information, said right lane marker position information, and said another vehicle speed information is worked out according to said image information.

12. The automatic driving device able to diagnose decisions according to claim 11, wherein said difference of distances to left and right lane markers is a difference between a distance between said present vehicle position information of said vehicle body information and said left lane marker position information of said traffic environment information and a distance between said present vehicle position information of said vehicle body information and said right lane marker position information of said traffic environment information.

13. The automatic driving device able to diagnose decisions according to claim 11, wherein said diagnostic equation is expressed by $L=\log \left\{\underset{t=1}{\overset{n}{.Math.}}\left[\frac{\begin{array}{c}{2}^{\underset{t=1}{\overset{2}{.Math.}}I\left(.Math.K_H\left(x_t\right)-K_i\left(x_t\right).Math.\ge {\mathrm{.Math.}}_K\right)}{3}^{I\left(D-V/2\le 0\right)}\\ 7^{I\left(a_H{J}_H/{\mathrm{SR}}_H\ge {\mathrm{.Math.}}_A\right)}{13}^{I\left(\mathrm{LTR}\ge {\mathrm{.Math.}}_L\right)}\end{array}}{\begin{array}{c}{5}^{I\left(.Math.D_L\left(x_t,y_t\right)-D_R\left(x_t,y_t\right).Math.\ge {\mathrm{.Math.}}_D\right)}\\ {11}^{I\left(\mathrm{do}\mathrm{LG}\right)\left[I\left({\mathrm{TTC}}_H\left(\mathrm{Forward}\right)\le {\mathrm{.Math.}}_F\right).Math.I\left({\mathrm{TTC}}_R\left(\mathrm{Host}\right)\le {\mathrm{.Math.}}_R\right)\right]}\end{array}}\right]\right\}$ wherein L is said deviation value; I() is said indicator function; K.sub.H(x.sub.t) is said future driving curvature at said present vehicle coordinate information x.sub.t; K.sub.i(x.sub.t) is said lane marker curvature information at said present vehicle coordinate information x.sub.t; ε.sub.K is a tolerance of curvature; D is said distance to another vehicle; V is said present vehicle speed information; a.sub.H is said present vehicle acceleration-deceleration information; J.sub.H is present vehicle jerk information; SR.sub.H is said present vehicle steering wheel angular velocity information; (a.sub.HJ.sub.H/SR.sub.H) is the equation for calculating lateral slide displacement index; ε.sub.A is said tolerance of lateral slide displacement; LTR is said vehicle turnover index; ε.sub.L is said tolerance of turnover; D.sub.L(x.sub.t,y.sub.t) is said distance between said present vehicle coordinate information x.sub.t,y.sub.t and said left lane marker position information; D.sub.R (x.sub.t,y.sub.t) is said distance between said present vehicle coordinate information x.sub.t,y.sub.t and said right lane marker position information; ε.sub.D is said tolerance of difference of distances to left and right lane markers; TTC.sub.H(Forward) is said forward collision time index; ε.sub.F is said tolerance of forward collision time; TTC.sub.R(Host) is said rear collision time index; ε.sub.R is said tolerance of rear collision time; 2, 3, 5, 7, 11, and 13 are said representative numerals respectively representing different events; do LG(do lane change) is an event that said present vehicle changes lanes.

14. The automatic driving device able to diagnose decisions according to claim 8, wherein after said central processor transmits said notification information to said automatic driving controller, said automatic driving controller interrupts automatic driving.

15. The automatic driving device able to diagnose decisions according to claim 8, wherein said central processor modifies said future driving track to generate a new future driving track and make said curvature difference, said neighboring vehicle distance index, said lateral slide displacement index, said vehicle turnover index, said difference of distances to left and right lane markers, said forward collision time index, and said rear collision time index respectively meet said tolerance of curvature, said tolerance of distance to a neighboring vehicle; said tolerance of lateral slide displacement, said tolerance of turnover, said tolerance of difference of distances to left and right lane makers, said tolerance of forward collision time, and said tolerance of rear collision time, and wherein said central processor transmits said new future driving track to said automatic driving controller to enable said automatic driving controller to undertake automatic driving according to said new future driving track.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a block diagram schematically showing the architecture of an automatic driving device able to diagnose decisions according to one embodiment of the present invention;

(2) FIG. 2 is a flowchart schematically showing an automatic driving method able to diagnose decisions according to one embodiment of the present invention;

(3) FIG. 3 is a diagram schematically showing calculation of difference of curvatures according to one embodiment of the present invention; and

(4) FIG. 4 is a diagram schematically showing calculation of difference of the distances to the left and right lane markers.

DETAILED DESCRIPTION OF THE INVENTION

(5) Refer to FIG. 1 for the architecture of an automatic driving device 1 able to diagnose decisions of the present invention. The automatic driving device 1 comprises at least one vehicle body signal sensor 10; at least one environment sensor 12; a central processor 14; and an automatic driving controller 16. The vehicle body signal sensor 10 detects the present vehicle to generate vehicle body information. The vehicle body information includes present vehicle steering wheel angular velocity information, present vehicle speed information, present vehicle acceleration-deceleration information, and present vehicle coordinate information. The environment sensor 12 detects external environment to generate traffic environment information. The central processor 14 is electrically connected with the vehicle body signal sensor 10, the environment sensor 12, and the automatic driving controller 16. The central processor 14 receives the vehicle body signals generated by the vehicle body signal sensor 10 and the traffic environment information generated by the environment sensor 12. The central processor 14 works out a future driving track according to the vehicle body signals and introduces the future driving track and the traffic environment information into a diagnostic equation to diagnose whether the future driving track is safe. If the future driving track is safe, the central processor 14 transmits the future driving track to the automatic driving controller 16 to implement automatic driving. If the future driving track is unsafe, the central processor 14 sends a notification to the automatic driving controller 16 to stop the vehicle or modify the future driving track.

(6) Refer to FIG. 1 again for the details of the vehicle body signal sensor 10. In the embodiment shown in FIG. 1, the automatic driving device 1 comprises a plurality of vehicle body signal sensors 10, including a steering wheel angular velocity sensor 102, a vehicle speed sensor 104, and a position sensor 106. The steering wheel angular velocity sensor 102 generates the present vehicle steering wheel angular velocity information of the vehicle body information. The vehicle speed sensor 104 generates the present vehicle speed information and the present vehicle acceleration-deceleration information of the vehicle body information.

(7) The position sensor 106 may be a global positioning system (GPS), generating the present vehicle coordinate information of the vehicle body information.

(8) The environment sensor 12 may be a radar sensor or an image sensor. In this embodiment, the environment sensor 12 is an image sensor 122, such as a camera device capturing the surrounding images to generate image information. According to the image information, the following information can be worked out, including lane marker curvature information, distance to another vehicle information, left lane marker position information, right lane marker position information, and another vehicle speed information. The image information of the image sensor 122 may be used to determine the relative coordinate information of the present vehicle coordinate information and another vehicle coordinate information. For example, let the present vehicle coordinate information always be (0, 0); the position of another vehicle or a barrier can be worked out with the distance from the present vehicle to another vehicle or the barrier. In such a case, the present vehicle coordinate information and another vehicle coordinate information can be generated without using the position sensor 106. In this embodiment, the position sensor 106 is exemplarily used to generate coordinate information.

(9) After the architecture of an automatic driving device 1 able to diagnose decisions has been described above, the automatic driving method able to diagnose decisions of the present invention will be described below. Refer to FIG. 1 and FIG. 2. In the embodiment shown in FIG. 2, the method of the present invention comprises steps S10-S18. In Step S10, the central processor 14 receives vehicle body information of a present vehicle from the vehicle body signal sensor 10 and traffic environment information generated by the environment sensor 12. The vehicle body information includes present vehicle steering wheel angular velocity information, present vehicle speed information, present vehicle acceleration-deceleration information, and present vehicle coordinate information. The traffic environment information includes lane marker curvature information, distance to another vehicle information, left lane marker position information, right lane marker position information, and another vehicle speed information.

(10) In Step S12, the central processor 14 generates a future driving track of the present vehicle according to the vehicle body information. The future driving track includes lane marker curvature information, a neighboring vehicle distance index, a lateral slide displacement index, a vehicle turnover index, a forward collision time index, and a rear collision time index. In Step S14, the central processor 14 introduces the future driving track and the traffic environment information into a diagnostic equation to determine whether the difference value between the future driving track and the traffic environment information and the index of the future driving track respectively meet tolerances.

(11) The diagnostic equation will be interpreted mathematically. The diagnostic equation is expressed by

(12) $L=\log \left\{\underset{t=1}{\overset{n}{.Math.}}\left[\frac{\begin{array}{c}{2}^{\underset{t=1}{\overset{2}{.Math.}}I\left(.Math.K_H\left(x_t\right)-K_i\left(x_t\right).Math.\ge {\mathrm{.Math.}}_K\right)}{3}^{I\left(D-V/2\le 0\right)}\\ 7^{I\left(a_H{J}_H/{\mathrm{SR}}_H\ge {\mathrm{.Math.}}_A\right)}{13}^{I\left(\mathrm{LTR}\ge {\mathrm{.Math.}}_L\right)}\end{array}}{\begin{array}{c}{5}^{I\left(.Math.D_L\left(x_t,y_t\right)-D_R\left(x_t,y_t\right).Math.\ge {\mathrm{.Math.}}_D\right)}\\ {11}^{I\left(\mathrm{do}\mathrm{LG}\right)\left[I\left({\mathrm{TTC}}_H\left(\mathrm{Forward}\right)\le {\mathrm{.Math.}}_F\right).Math.I\left({\mathrm{TTC}}_R\left(\mathrm{Host}\right)\le {\mathrm{.Math.}}_R\right)\right]}\end{array}}\right]\right\}$
wherein L is the deviation value; I() is the indicator function; K.sub.H(x.sub.t) is the future driving curvature at the present vehicle coordinate information x.sub.t; K.sub.i(x.sub.t) is the lane marker curvature information at the present vehicle coordinate information x.sub.t; (|K.sub.H(x.sub.t)−K.sub.i(x.sub.t)|) is the equation for calculating curvature difference; ε.sub.R is the tolerance of curvature; D is the distance to another vehicle information; V is the present vehicle speed information; (D−V/2) is the equation for calculating the neighboring vehicle distance index; a.sub.H is the present vehicle acceleration-deceleration information; J.sub.H is the present vehicle jerk information; SR.sub.H is the present vehicle steering wheel angular velocity information; (a.sub.HJ.sub.H/SR.sub.H) is the equation for calculating lateral slide displacement index; ε.sub.A is the tolerance of lateral slide displacement; LTR (Load Transfer Ration) is the vehicle turnover index; ε.sub.L is the tolerance of turnover; D.sub.L(x.sub.t,y.sub.t) is the distance between the present vehicle coordinate information x.sub.t,y.sub.t and the left lane marker position information; D.sub.R (x.sub.t, y.sub.t) is the distance between the present vehicle coordinate information x.sub.t,y.sub.t and the right lane marker position information; (|D.sub.L(x.sub.t,y.sub.t)−D.sub.R(x.sub.t,y.sub.t)|) is the equation for calculating the difference of the distance to the left lane marker and the distance to the right lane marker; ε.sub.D is the tolerance of difference of distances to left and right lane markers; TTC.sub.H(Forward) is the forward collision time index; ε.sub.F is the tolerance of forward collision time; TTC.sub.R(Host) is the rear collision time index; ε.sub.R is the tolerance of rear collision time; 2, 3, 5, 7, 11, and 13 are the numerals respectively representing different events; do LG(do lane change) is the event that the present vehicle changes lanes.

(13) In other words, introduction of the future driving track and the traffic environment information into the diagnostic equation implements calculating the difference values between the future driving track and the traffic environment information, such as the difference of curvatures and the difference of the distances to the left and right lane markers. Refer to FIG. 3 for the calculation of the difference of curvatures. The future driving curvature K.sub.H(x.sub.t) is compared with the lane marker curvature information K.sub.H(x.sub.t) to obtain the absolute value of the difference of curvatures (|K.sub.H(x.sub.t)−K.sub.i(x.sub.t)|), whereby to check whether the difference of curvatures is within the curvature tolerance ε.sub.K. Refer to FIG. 4 for the calculation of the difference of the distances to the left and right lane markers. The distance between the present vehicle position information x.sub.t,y.sub.t of the vehicle body information and the left lane marker position information a of the traffic environment information is expressed by D.sub.L(x.sub.t,y.sub.t). The distance between the present vehicle position information x.sub.t,y.sub.t of the vehicle body information and the right lane marker position information b of the traffic environment information is expressed by D.sub.R(x.sub.t,y.sub.t). The absolute value of the difference of the two distances (|D.sub.L(x.sub.t,y.sub.t)−D.sub.K(x.sub.t,y.sub.t)|) is worked out to determine whether it is within the tolerance of the difference of the distances to the left and right lane markers ε.sub.D. The diagnostic equation also examines a plurality of indexes of the future driving track, e.g. checks whether the neighboring vehicle distance index (D−V/2) is within the tolerance of the distance to a neighboring vehicle; checks the lateral slide displacement index (a.sub.HJ.sub.H/SR.sub.H) is within the tolerance of lateral slide displacement ε.sub.A; checks whether the vehicle turnover index (LTR) is within the tolerance of turnover ε.sub.L; checks whether the forward collision time index TTC.sub.H (Forward) is within the tolerance of forward collision time ε.sub.F; checks whether the rear collision time index TTC.sub.R(Host) is within the tolerance of rear collision time ε.sub.R.

(14) Refer to FIG. 2 again. As mentioned above, the central processor 14 introduces the future driving track and the traffic environment information into a diagnostic equation to determine whether each of the tolerances is satisfied. If each of the tolerances is satisfied, the process proceeds to Step S16. In Step S16, the deviation generated by the diagnostic equation has a value of zero. However, the value of zero is only for exemplification. The present invention does not limit that deviation must has a value of zero. In such a case, the central processor 14 transmits the future driving track to the automatic driving controller 16, and the automatic driving controller 16 automatically drive the present vehicle according to the future driving track.

(15) If it is determined that not all the tolerances are satisfied in Step S14, the process proceeds to Step S18, and the diagnostic equation generates a deviation having a non-zero value. The non-zero value is only for exemplification. The present invention does not limit that the value of the deviation must be in form of Arabic numerals. In such a case, the central processor 14 transmits notification information to the automatic driving controller 16 to instruct the automatic driving controller 16 to interrupt automatic driving. Alternatively, after generating the notification information, the central processor 14 modifies the future driving track to make the difference of curvatures, the neighboring vehicle distance index, the lateral slide displacement index, the vehicle turnover index, the difference of the distances to the left and right lane markers, the forward collision time index, and the rear collision time index respectively meet the curvature tolerance, the tolerance of the distance to a neighboring vehicle, the tolerance of lateral slide displacement, the tolerance of turnover, the tolerance of the difference of the distances to the left and right lane markers, the tolerance of forward collision time, and the tolerance of rear collision time. Thereby, a new future driving track is generated by the central processor 14 and transmitted to the automatic driving controller 16. Thus, the automatic driving controller 16 undertakes automatic driving according to the new future driving track.

(16) The notification information includes the deviation value L worked out by the diagnostic equation. The number of the deviation value L is meaningful. In detail, the numerals 2, 3, 5, 7, 11, and 13 respectively represent different events and dominate the calculation of the deviation value L. Thereby, the user can fast recognize which one of the indexes or difference values does not meet the tolerance.

(17) For example, while the worked out deviation value L=0, it means that all the indexes and difference values meet the tolerances. While the worked out deviation value L=n log 2, it means that the difference of the curvatures, which is worked from (+K.sub.H(x.sub.t)−K.sub.i(x.sub.t)|), does not meet the tolerance of curvatures. While the worked out deviation value L=n log 3, it means that the neighboring vehicle distance index, which is worked out from (D−V/2), does not meet the tolerance of the distance to a neighboring vehicle. The cases of the other numerals 5, 7, 11, and 13 are similar to the cases mentioned above and will not repeat herein. Naturally, it is possible that two or more indexes or difference values do not meet the tolerances. For example, while L=n log 6, it may indicate the events, which are respectively associated with (|K.sub.H(x.sub.t)−K.sub.i(x.sub.t)|) and (D−V/2) and separately represented by 2 and 3 because 6 is the product of 2 and 3. Therefore, the representative numerals must be prime numbers so that the represented events can be recognized without confusion.

(18) In conclusion, the present invention can automatically examine an automatic driving-assistant system to judge whether the future driving track, the curvature of the present road, the distances to the lane markers, the distance to a barrier, etc. are within the tolerances thereof and thus determine whether the automatic driving track is safe. The present invention can also use the diagnostic equation to directly determine the parameters needing calibration in the future driving track, whereby the central processor can modify the parameters to improve the safety of automatic driving.

(19) The embodiments described above are only to exemplify the present invention but not to limit the scope of the present invention. Any equivalent modification or variation according to the spirit and characteristics of the present invention is to be also included by the scope of the present invention.