Vehicle collision avoidance system and method

• US 7,089,114 B1
• Filed: 07/03/2003
• Issued: 08/08/2006
• Est. Priority Date: 07/03/2003
• Status: Expired due to Fees

• Current Assignee: Baojia Huang
• Original Assignee: Baojia Huang
• Inventors: Huang, Baojia
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): Gibson, Eric M.
• Application Number:
  US10/613,885
• Time in Patent Office: 1,132 Days
• Field of Search: 701/70, 701/96, 701/97, 701/301, 340/435, 340/436, 340/903, 340/904
• US Class Current: 701/301
• CPC Class Codes: B60T 7/22 initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle , or by means of contactless obstacle detectors mounted on the vehicle
• CPC Class Codes: G01S 17/931 of land vehicles

Abstract

A vehicle collision avoidance system includes a 360 degree circumferentially rotating pulsed infrared laser beam scanner apparatus which rotates in a horizontal plane and a vertical plane simultaneously for generating a first signal representative of an obstacle. An analog processing circuit is coupled to the circumferentially rotating pulsed infrared laser beam scanner apparatus for processing the first signal and generating a plurality of signals. A processor is coupled to the processing circuit for processing the plurality of signals and generating a braking signal and providing a braking apparatus with the braking signal. Associated methods are also provided. The system and method of the invention are based on a second order model which characterizes the relationship in both space and time between the vehicle and the obstacle. The circumferentially rotating pulsed infrared laser beam scanner apparatus includes an eye-safe laser apparatus in terms of peak power, pulse width, repetition rate and divergent angle.

Claims

1. A vehicle collision avoidance system comprising:

a circumferentially rotating pulsed infrared laser beam scanner apparatus including a laser pulsed emitter and an infrared laser sensor for generating a first signal representative of an obstacle scanned, the laser pulsed emitter rotating circumferentially in a horizontal plane and a vertical plane simultaneously, the infrared laser sensor circumferentially rotating synchronously with the laser pulsed emitter in the horizontal plane and receiving a reflected laser beam signal from the obstacle scanned;

wherein the laser pulsed emitter is emitting a laser beam signal over a 360°

field of view and the infrared laser sensor is receiving the reflected laser beam signal over the 360°

field of view;

a processing circuit coupled to the circumferentially rotating pulsed infrared laser beam scanner apparatus for processing the first signal and generating a plurality of signals;

a processor coupled to the processing circuit for processing the plurality of signals and generating a braking signal; and

a braking apparatus responsive to the braking signal.

2. The vehicle collision avoidance system of claim 1, wherein the circumferentially rotating pulsed infrared laser beam scanner apparatus is operable to scan an object from 1.6 m to 120 m.

3. The vehicle collision avoidance system of claim 1, wherein the circumferentially rotating pulsed infrared laser beam scanner apparatus rotates in the horizontal plane at 48 revolutions per second and with a period of 20.83 ms and in the vertical plane at 8 sectors per second and a period of 20.83 ms.

4. The vehicle collision avoidance system of claim 1, wherein the circumferentially rotating pulsed infrared laser beam scanner apparatus emits a laser beam having 28.45W peak power, an average power of 142 mW, a wavelength between 1 μ

m and 1.550 μ

m excluding the region between 1.3 μ

m and 1.4 μ

m, and preferably between 1.450 μ

m and 1.550 μ

m, a 1.0 ns to 1.25 ns pulse width, a 10 Mhz to 110 Mhz repetition rate, and a 0.002 radian emitting pulsed laser beam divergent angle.

5. A method of avoiding a vehicle collision comprising:

determining features of an obstacle using a circumferentially rotating pulsed infrared laser beam scanner apparatus including a laser pulsed emitter and an infrared laser sensor for generating a first signal representative of the obstacle scanned, the laser pulsed emitter rotating circumferentially in a horizontal plane and a vertical plane simultaneously, the infrared laser sensor circumferentially rotating synchronously with the laser pulsed emitter in the horizontal plane and receiving a reflected laser beam signal from the obstacle scanned;

wherein the laser pulsed emitter is emitting a laser beam signal over a 360°

field of view and the infrared laser sensor is receiving the reflected laser beam signal over the 360°

field of view;

processing signals representative of the determined features, and

braking the vehicle in the event the processed signals indicate an imminent collision.

6. The method of avoiding a vehicle collision of claim 5, wherein the circumferentially rotating pulsed infrared laser beam scanner apparatus emits a laser beam having 28.45W peak power, an average power of 142 mW, a wavelength between 1 μ

m and 1.550 μ

m excluding the region between 1.3 μ

m and 1.4 μ

m, and preferably between 1.450 μ

m and 1.550 μ

m, a 1.0 ns to 1.25 ns pulse width, a 10 Mhz to 110 Mhz repetition rate, and a 0.002 radian emitting pulsed laser beam divergent angle.

7. A method of avoiding a vehicle collision comprising:

circumferentially detecting bodies proximate the vehicle using a circumferentially rotating pulsed infrared laser beam scanner apparatus including a laser pulsed emitter and an infrared laser sensor for generating a first signal representative of a body scanned, the laser pulsed emitter rotating circumferentially in a horizontal plane and a vertical plane simultaneously, the infrared laser sensor circumferentially rotating synchronously with the laser pulsed emitter in the horizontal plane and receiving a reflected laser beam signal from the body scanned;

wherein the laser pulsed emitter is emitting a laser beam signal over a 360°

field of view and the infrared laser sensor is receiving the reflected laser beam signal over the 360°

field of view;

obtaining data from the circumferentially rotating pulsed infrared laser beam scanner apparatus including a time when the beam reaches a first edge of each body and a time when the beam reaches a second edge of each body;

determining a relative distance from the scanner apparatus to each body;

determining a time to collision with each body; and

determining a braking force to avoid a collision with each body.

8. The method of avoiding a vehicle collision of claim 7, further comprising determining a critical point at which an absolute value of the derivative of each bodies acceleration with respect to time approaches zero.

9. The method of avoiding a vehicle collision of claim 8, wherein determining the relative distance and determining the time to collision are initiated at the critical point.

10. The method of avoiding a vehicle collision of claim 7, further comprising determining a relative angular velocity of each body.

11. The method of avoiding a vehicle collision of claim 7, wherein determining the time to collision comprises computing a second order factor.

12. The method of avoiding a vehicle collision of claim 7, further comprising determining the bumpiness of a road surface.

13. The method of avoiding a vehicle collision of claim 12, wherein determining the braking force to avoid a collision with each obstacle comprises determining a first braking force in a case where the time to collision is less than 1.5 seconds and a second braking force in a case where the road is bumpy.

14. The method of avoiding a vehicle collision of claim 7, wherein determining the time to collision further comprises determining vertical and horizontal components of each body.

15. The method of avoiding a vehicle collision of claim 7, further comprising determining a rate of approach of the vehicle and each body.

16. The method of avoiding a vehicle collision of claim 7, wherein the obtaining and determining steps are performed in a point-to-point vector processing manner.

17. The method of avoiding a vehicle collision of claim 7, further comprising using an analog circuit to process the time when the beam reaches the first edge of each body and the time when the beam reaches the second edge of each body, the relative distance from the scanner apparatus to each body, a relative angular velocity of each body, an acceleration of each body, and a derivative of the acceleration.