Collision warning system
AssigneeMobileye Technologies Ltd.
InventorsGideon P. Stein, Erez Dagan, Ofer Mano, Amnon Shashua
Life of this patent
Estimating the term…
Abstract
A method of estimating a time to collision (TTC) of a vehicle with an object comprising: acquiring a plurality of images of the object; and determining a TTC from the images that is responsive to a relative velocity and relative acceleration between the vehicle and the object.
Claims24
A method of estimating a time-to-collision (TTC) of a vehicle with an object comprising the step of:
- (a) acquiring a plurality of images of the object at known time intervals between the times t at which the images are acquired;
- (b) determining a momentary time Tv(t), which is equal to an instantaneous distance between the vehicle and the object at time t divided by an instantaneous relative velocity, from information derived from the images and the time intervals;
- and
- determining the time-to-collision (TTC) based on a rate of change over times t of momentary time Tv(t).
A method of estimating a time-to-collision (TTC) of a vehicle with an object comprising the step of:
- (a) acquiring a plurality of images of the object at known time intervals between the times at which the images of the plurality of images are acquired;
- and
- (b) determining the time-to-collision (TTC) from information derived from the images and the time intervals, wherein said determining the TTC is based on a relative velocity and relative acceleration between the vehicle and the object, wherein said (b) determining the time-to-collision (TTC) includes determining a change in scale of an image of at least a portion of the object and using the change in scale for determining a function of the relative velocity, wherein said determining the change in scale includes determining a ratio between a dimension of the object in a first one of the images and the same dimension of the object in a second one of the images, wherein said determining a function of the relative velocity includes determining a function Tv=[1/(S−1)]ΔT, where S is the ratio and ΔT is a time lapse between two images of the images, wherein a function of the relative acceleration is determined based on a time derivative T′v, of function Tv.
A method of determining whether a vehicle and an object are on a collision course, the method comprising the steps of:
- (a) acquiring a plurality of images of the object from a position in the vehicle at a plurality of known times;
- (b) determining, from the images, respective motions in image space of at least two features of the object relative to the vehicle;
- (c) determining from the images an estimate of a time to collision (TTC) of the vehicle and the object;
- and
- (d) determining from the motions whether at the TTC, the real-space horizontal coordinates of said at least two features straddle the real-space horizontal coordinate of the position in the vehicle, whereby the vehicle and object are on a collision course.
Dependencies are inferred from the claim text.