Method, computer program and device for determining the risk of midair collision

• US 7,969,289 B2
• Filed: 09/15/2008
• Issued: 06/28/2011
• Est. Priority Date: 09/14/2007
• Status: Expired due to Fees

• Current Assignee: Saab AB
• Original Assignee: Saab AB
• Inventors: Nordlund, Per-Johan
• Primary Examiner(s): Previl; Daniel
• Application Number:
  US12/210,806
• Publication Number:
  US 20090102630A1
• Time in Patent Office: 1,016 Days
• Field of Search: 340/436, 340/425.5, 340901-903, 340/435, 340/904, 701/300, 701/301, 701/93, 701/96, 701/45
• US Class Current: 340/436
• CPC Class Codes: G01S 11/12 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/20076 Probabilistic image processing
• CPC Class Codes: G06T 2207/30212 Military
• CPC Class Codes: G06T 2207/30248 Vehicle exterior or interior
• CPC Class Codes: G06T 2207/30261 Obstacle
• CPC Class Codes: G06T 7/277 involving stochastic approaches, e.g. using Kalman filters
• CPC Class Codes: G06T 7/73 using feature-based methods
• CPC Class Codes: G08G 5/045 Navigation or guidance aids, e.g. determination of anti-collision manoeuvers radar or analogous systems specially adapted for anti-collision between aircraft G01S13/933

Abstract

A method for determining the probability of a vehicle colliding with a detected object. The object is detected. A stochastic process is determined representing a relative distance between the vehicle and the detected object. The stochastic process has a direction and a velocity relative the vehicle. A safety zone of the vehicle is defined in relation to the detected object as a straight line perpendicular to a line of sight of the detected object. The probability of colliding with the detected object over a period of time is determined as the probability of the stochastic process crossing the straight line with the direction and velocity of the stochastic process.

Claims

1. A method for determining a probability of a vehicle colliding with an object, the method comprising:

detecting the object,

determining a stochastic process representing a relative distance between the vehicle and the detected object, the stochastic process having a direction and a velocity relative the vehicle,

defining a safety zone of the vehicle in relation to the detected object as a straight line perpendicular to a line of sight of the detected object, and

determining the probability of colliding with the detected object over a period of time as the probability of the stochastic process crossing the straight line with the direction and velocity of the stochastic process.

2. The method according to claim 1, wherein detecting the object comprises capturing an image with an optical sensor mounted on the vehicle and registering the object in the image, the method further comprising:

determining a relative position and velocity of the detected object, and thereby a position, a direction and a velocity relative the vehicle, by a target tracking unit arranged in the vehicle, and

determining the probability of colliding with the detected object over a period of time by considering the stochastic process and the probability of colliding with the detected object is set to be the probability of the stochastic process, with the position as an initial value, crossing the straight line taken the direction and velocity from the target tracking unit as the direction and velocity of the stochastic process.

3. The method according to claim 1, wherein the determining of the probability further comprises rotating a coordinate system such that an x-axis of the coordinate system is aligned with a x-axis of coordinate system and wherein the straight line of the safety zone has two end points and defining a predetermined length of the line and wherein the straight line is perpendicular to the x-axis of the coordinate system.

4. The method according to claim 1, wherein the safety zone is defined by a rectangular or an elliptic plane toward the detected object and the stochastic process is defined as a three dimensional entity and that the coordinate system further comprises a z-axis.

5. The method according to claim 4, the collision, near mid-air collision (NMAC), between the vehicle and the object is expressed as

6. The method according to claim 4, the collision, near mid-air collision (NMAC), between the vehicle and the object is expressed as

7. The method according to claim 1, wherein the collision, near mid-air collision (NMAC), between the vehicle and the object is expressed as

8. A computer program product, comprising:

a computer readable medium; and

computer program instructions recorded on the computer readable medium and executable by a processor for carrying out a method for determining a probability of a vehicle colliding with an object, the method comprising detecting the object, determining a stochastic process representing a relative distance between the vehicle and the detected object, the stochastic process having a direction and a velocity relative the vehicle, defining a safety zone of the vehicle in relation to the detected object as a straight line perpendicular to a line of sight of the detected object, and determining the probability of colliding with the detected object over a period of time as the probability of the stochastic process crossing the straight line with the direction and velocity of the stochastic process.

9. A processor, comprising:

a computer program product installed thereon, the computer program product comprising a computer readable medium, and computer program instructions recorded on the computer readable medium and executable by a processor for carrying out a method for determining a probability of a vehicle colliding with an object, the method comprising detecting the object, determining a stochastic process representing a relative distance between the vehicle and the detected object, the stochastic process having a direction and a velocity relative the vehicle, defining a safety zone of the vehicle in relation to the detected object as a straight line perpendicular to a line of sight of the detected object, and determining the probability of colliding with the detected object over a period of time as the probability of the stochastic process crossing the straight line with the direction and velocity of the stochastic process.

10. An unmanned vehicle comprising:

an optical sensor,

a target tracking unit, and

a processor comprising a computer program product installed thereon, the computer program product comprising a computer readable medium, and computer program instructions recorded on the computer readable medium and executable by a processor for carrying out a method for determining a probability of a vehicle colliding with an object, the method comprising detecting the object, determining a stochastic process representing a relative distance between the vehicle and the detected object, the stochastic process having a direction and a velocity relative the vehicle, defining a safety zone of the vehicle in relation to the detected object as a straight line perpendicular to a line of sight of the detected object, and determining the probability of colliding with the detected object over a period of time as the probability of the stochastic process crossing the straight line with the direction and velocity of the stochastic process.