Vehicle roll over prevention safety driving system and method

• US 8,489,287 B2
• Filed: 12/31/2010
• Issued: 07/16/2013
• Est. Priority Date: 12/31/2010
• Status: Active Grant

• Current Assignee: Automotive Research & Testing Center
• Original Assignee: Automotive Research & Testing Center
• Inventors: Su, Yi-Feng, Hsu, Tsung-Hua, Chen, Chun-Hsiung, Hsu, Tzu-Chien, Liao, Hsueh-Lung
• Primary Examiner(s): Trammell, James
• Assistant Examiner(s): GREENE, DANIEL LAWSON
• Application Number:
  US12/982,953
• Publication Number:
  US 20120173083A1
• Time in Patent Office: 928 Days
• Field of Search: 701/45, 701/65, 701/70, 701/72, 701/80, 180/271, 180/275, 180/279, 180/282, 180/283, 180/284, 180/285
• US Class Current: 701/45
• CPC Class Codes: B60T 2210/22 Banked curves
• CPC Class Codes: B60T 2230/03 Overturn, rollover
• CPC Class Codes: B60T 8/17554 specially adapted for enhancing stability around the vehicles longitudinal axle, i.e. roll-over prevention road vehicle drive control systems for roll-over prevention otherwise than by controlling a particular sub-unit B60W30/04

Abstract

A vehicle rollover prevention safety driving system, comprising: at least an image sensor, used to fetch road images in front of said vehicle; an image processor, connected to said image sensor, and is used to identify a drive lane in road images, and calculate a drive lane curvature, an inclination angle of said road, and relative positions of said vehicle and a lane marking; a vehicle conditions sensing module, used to sense dynamic information of a vehicle turning angle, a vehicle inclination angle, and a vehicle speed; a microprocessor, connected to said image processor and said vehicle conditions sensing module, and it calculates a rollover prediction point and a rollover threshold speed, and it issues a corresponding warning signal or a control signal; and an accelerator and brake controller, connected to said microprocessor, and it controls deceleration of said vehicle according to said control signal.

Claims

1. A vehicle rollover prevention safety driving method, comprising the following steps:

(A) fetching at least a road image in front of said vehicle;

(B) determining if drive lanes are in a road image, in case the answer is negative, return to step (A), otherwise perform step (C);

(C) calculating by a processor a curvature of said drive lane, inclination angle of the road, and the relative positions of said vehicle on said drive lane based on a lane marking;

(D) calculating a rollover prediction point and a rollover threshold speed based on vehicle dynamic information, said curvature of the drive lane, said inclination angle of the road; and

(E) determining if said vehicle speed is over a rollover threshold speed;

in case the answer if negative, returning to said step (C);

otherwise, issuing a warning to driver to slow down said vehicle relative to said rollover prediction point and said rollover threshold speed, wherein in said step (C), a lane marking model is utilized to calculate a slope of said drive lane, said curvature of said drive lane, and said relative positions of said vehicle on said drive lane, wherein the equation of the lane marking model is;

X_w=k·

Y_w²+m·

Y_w+b,

wherein X_w and Y_w indicate world coordinate axes, respectively, and k, m, and b are parameters of said lane marking model,

wherein the slope E_l of said drive lane is obtained by applying a first order differentiation to said lane marking model, where E_l=2·

kY_w+m,

wherein said curvature C_l of the drive lane is obtained by applying a second order differentiation to said lane marking model, where C_l=2·

k, and

wherein said relative positions Δ

Y of said vehicle on said drive lane are obtained as;

2. The vehicle rollover prevention safety driving method, as claimed in claim 1, wherein said lane marking model is based on a world coordinate, and an image processor is used to project said lane marking model onto said lane marking model based on an image coordinate, further comprising the steps of:

performing corresponding coordinate transformation, and

applying a perspective vision processing method to calculate an error correction value of inclination angle of said drive lane.

3. The vehicle rollover prevention safety driving method, as claimed in claim 1,

wherein said rollover threshold speed is obtained through the following equation:

4. The vehicle rollover prevention safety driving method, as claimed in claim 1, further comprising the steps of:

in said step (C) of calculating said inclination angle of road based on said lane marking by;

(C1) utilizing a perspective vision processing method to obtain a road in-depth image;

(C2) defining said road of said lane marking is a planar road or a non-planar road based on said road in-depth image; and

(C3) calculating said road horizontal or road vertical in obtaining said inclination angle of said road.

5. The vehicle rollover prevention safety driving method, as claimed in claim 4, wherein said perspective vision processing method is used to obtain an in-depth image of said road, such that through two corresponding images as taken by two image sensors, restore an actual distance between an actual road image and a fetched road image, an equation for calculating said actual distance is:

6. A vehicle rollover prevention safety driving system, comprising:

at least an image sensor, said image sensor being adapted to fetch road images in front of said vehicle;

an image processor connected to said image sensor, said image processor being adapted to identify a drive lane in road images, and calculate a drive lane curvature, an inclination angle of said road, and relative positions n of said vehicle and a lane marking based on said lane marking model;

a vehicle conditions sensing module sensing dynamic information of a vehicle turning angle, a vehicle inclination angle, and a vehicle speed;

a microprocessor, connected to said image processor and said vehicle conditions sensing module, and calculating a rollover prediction point and a rollover threshold speed based on a curvature of the road, said inclination angle of said road, and said dynamic information, wherein said microprocessor issues a corresponding warning signal or a control signal; and

an accelerator and brake controller connected to said microprocessor, said accelerator and brake controller controlling deceleration of said vehicle according to said control signal,

wherein said image processor utilizes a lane marking model to calculate a slope of said drive lane, said drive lane curvature, and relative positions of said vehicle on said drive lane,

wherein the equation of the lane marking model is;

X_w=k·

Y_w²+m·

Y_w+b,

wherein X_w and Y_w indicate world coordinate axes, respectively, and k, m, and b are parameters of said lane marking model,

wherein the slope E_l of said drive lane is obtained by applying a first order differentiation to said lane marking model, where E_l=2·

kY_w+m,

wherein said curvature C_l of the drive lane is obtained by applying a second order differentiation to said lane marking model, where C_l=2·

k, and

wherein said relative positions Δ

Y of said vehicle on said drive lane are obtained as;

7. The vehicle rollover prevention safety driving system, as claimed in claim 6,

wherein said vehicle conditions sensing module further comprises:

an inclination sensor adapted to sense an inclination angle of a vehicle;

an accelerator sensor adapted to detect speed of said vehicle; and

a steering wheel turning angle sensor adapted to sense a turning angle of said vehicle.

8. The vehicle rollover prevention safety driving system, as claimed in claim 6,

wherein said lane marking model is based on a world coordinate, and said image processor is adapted to project said lane marking model onto said lane marking model based on an image coordinate through performing corresponding coordinate transformation, and utilizing a perspective vision processing method to calculate an error correction value of said inclination angle of said drive lane.