Method for determining collision risk for collision avoidance systems

• US 8,095,313 B1
• Filed: 06/23/2008
• Issued: 01/10/2012
• Est. Priority Date: 06/23/2008
• Status: Expired due to Fees

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Blackburn, Michael R.
• Primary Examiner(s): Garg, Yogesh C
• Assistant Examiner(s): GEORGALAS, ANNE MARIE
• Application Number:
  US12/144,019
• Time in Patent Office: 1,296 Days
• Field of Search: 701/301, 701/300, 701/302, 180/271, 180/274, 340/435, 340/436
• US Class Current: 701/301
• CPC Class Codes: G08G 1/166 for active traffic, e.g. moving vehicles, pedestrians, bikes

Abstract

Disclosed is a method and apparatus for determining the risk of an object collision. The method includes transmitting a signal and analyzing a received signal that is indicative of the presence of a remote object. The signal is then analyzed to determine an initial azimuth value and an initial range for the remote object. Subsequent received signals are continuously analyzed to continuously determine subsequent azimuth values, azimuth value velocities and accelerations, as well as subsequent range values, range value velocities and range value accelerations. The factors are then input into a predetermined formula to yield a risk assessment of collision P. The formulas for determining P can be adjusted to account for such factors as number and proximity of remote objects, as well as the speed and maneuverability of both the remote objects and the vehicle that is avoiding collisions with the remote object(s).

Claims

1. An active collision detection apparatus mounted in a vehicle comprising:

a receiver that receives a received signal that is indicative of the presence of at least one remote object;

a processor that is configured to analyze said received signal to determine azimuth values θ

_t at time t for said at least one remote object, wherein said azimuth value θ

is an angle between a direction of travel of said vehicle and a line-of-sight to said at least one remote object, and to compute azimuth value velocities θ

V_t and azimuth value accelerations θ

A_t based on said azimuth values θ

_t;

said processor being further configured to analyze said received signal to determine initial range values R_t at time t for said at least one remote object, wherein said range value R is a distance between said at least one remote object and said vehicle and to compute range value velocities RV_t and range value accelerations RA_t based on said range values R_t;

wherein said processor is configured to determine a risk assessment P of collision of said vehicle with said at least one remote object according to a predetermined algorithm P_t=tan h(risk_factor*(range_risk+azimuth_risk)),

where

risk factor=(γ

*RV_t/R_t) where γ

is a scaling factor chosen according to the amount of said remote objects present around said vehicle,

range_risk=tan h(0.5+RA_t/RV_t) when RV_t>

0.0 else=0.0, and

azimuth_risk=tan h(0.5+θ

A_t/θ

V_t) when θ

V_t>

0.0;

else=1.0; and

,

wherein said determined value of P indicates a degree of collision risk.

2. The collision detection apparatus as recited in claim 1 further comprising a passive sensor that receives emitted or reflected signals from said at least one remote object.

3. The collision detection apparatus as recited in claim 1 further comprising an active sensor that receives emitted or reflected signals from said at least one remote object.