Abstract:
An improved probabilistic lane assignment method for detected objects (24) in the scene forward of a host vehicle (10). Road/lane model parameters, preferably including an angular orientation of the host vehicle (10) in its lane, are estimated from host vehicle sensor systems (26-36), taking into account measurement uncertainty in each of the constituent parameters. A probabilistic assignment of the object's lane is then assessed based on the road/lane model parameters and object measurements, again taking into account measurement uncertainty in both the road/lane model and object measurements (100-108). According to a first embodiment, the probabilistic assignment is discrete in nature, indicating a confidence or degree-of-belief that the detected object (24) resides in each of a number of lanes (94). According to a second embodiment, the probabilistic assignment is continuous in nature, providing a lateral separation distance between the host vehicle (10) and the object (24), and a confidence or degree-of-belief in the lateral separation distance (110).
Abstract:
An attitude angle estimator (80) and method of estimating attitude angle (82) of a vehicle having an angular attitude rate sensor (12) sensing angular attitude rate (13) of a vehicle, a vertical accelerometer (20) sensing vertical acceleration (21), and a lateral accelerometer (14) sensing lateral acceleration (15). An attitude angle estimate is produced and is updated as a function of the sensed angular attitude rate. An acceleration-based attitude angle (ϕ a ) is determined as a function of the sensed accelerations, and a blending coefficient (K) is provided. A current vehicle attitude angle estimate (82) is generated as a function of the updated attitude angle estimate, the acceleration-based attitude angle (ϕ a ), and the blending coefficient (K).
Abstract:
A method for estimating unknown parameters (pan angle ( ψ ), instantaneous tilt angle (τ) and road geometry of an upcoming road segment) for a vehicle object detection system (10). The vehicle object detection system is preferably a forward looking, radar-cued vision system having a camera (12), a radar sensor (14) and an processing unit (16). The method first estimates the pan angle ( ψ ), then corrects the coordinates from a radar track so that pan angle ( ψ ) can be treated as zero, and finally solves a least squares problem that determines best estimates for instantaneous tilt angle (τ) and road geometry. Estimating these parameters enables the vehicle object detection system (10) to identify, interpret and locate objects in a more accurate and efficient manner.
Abstract:
A method of lane marker detection and lane fitting is provided for lane tracking. A lane marker is modeled and split into left and right steps. A filter response is calculated from a cumulative row sum, and normalized for filter pixel size, lane marker brightness and road brightness. A lane marker response is peak detected for positive and negative peaks and checked for having a magnitude above a threshold and being a local peak in a five point neighborhood. A Hough transform is extended to multiple planes to use lane marker features to determine a best line. Lane marker features include a mean and variance of lane marker brightness, lane marker width, lane marker parallelism to a host vehicle direction of travel, and consistence with a predicted lane marker characteristic. A closest lane marker line to a host vehicle is identified, and refitted to account for any curvature.
Abstract:
A method of lane marker detection and lane fitting is provided for lane tracking. A lane marker is modeled and split into left and right steps. A filter response is calculated from a cumulative row sum, and normalized for filter pixel size, lane marker brightness and road brightness. A lane marker response is peak detected for positive and negative peaks and checked for having a magnitude above a threshold and being a local peak in a five point neighborhood. A Hough transform is extended to multiple planes to use lane marker features to determine a best line. Lane marker features include a mean and variance of lane marker brightness, lane marker width, lane marker parallelism to a host vehicle direction of travel, and consistence with a predicted lane marker characteristic. A closest lane marker line to a host vehicle is identified, and refitted to account for any curvature.
Abstract:
A vehicle rollover sensing apparatus (10) and method are provided for detecting an overturn condition of the vehicle. The rollover sensing apparatus (10) includes an angular rate sensor (12) for sensing attitude rate of change of a vehicle and producing an output signal indicative thereof. The rollover sensing apparatus also has an integrator (64) for integrating the sensed attitude rate of change signal over a variable time window (80) and producing an attitude angle. The rollover sensing apparatus further includes deployment logic (66) for comparing the attitude angle and attitude rate of change to a pair of variable threshold values, with a gray-zone (150) that varies based on time, and an output (56) for deploying a vehicle overturn condition signal based on the comparison. Adaptive bias removal and output minimum logic (62) reduces bias and noise associated with the sensed signal.
Abstract:
A collision detection system (18) and method (100) of estimating a miss distance (M) of an object (16) and estimating length (L) and width (W) of the object (16) are provided. The collision detection system (18) includes a sensor (12) for sensing an object (16) within a field of view (14) and measuring range (R) and range rate (R & ) of the sensed object. The collision detection system (18) further includes a controller (20) for estimating a miss distance (M) of the object (16) and further estimating length (L) and width (W) of the object (16) as a function of the range (R) and the range rate (R & ).