Travel route estimation device and travel route estimation method used in the same device
First Claim
1. A travel route estimation device comprising:
- a displacement velocity detection unit which detects a displacement velocity of one'"'"'s own-vehicle over a travel route surface;
a radius-of-curvature calculation unit which calculates, based on the displacement velocity, a plurality of radius of curvatures of a travel route of the own-vehicle;
a filtering process unit which conducts a filtering process on radius of curvatures up to a radius of curvature preceding a latest estimated radius of curvature by a predetermined number, among the plurality of radius of curvatures calculated by the radius-of-curvature calculation unit, and outputs a first radius of curvature and a second radius of curvature which is a value obtained at a same point as the first radius of curvature and has a lower responsivity to a change in the radius of curvature of the travel route of the own-vehicle than the first radius of curvature;
a weighted average unit which calculates, as a radius of curvature to be output to a safety apparatus of the own-vehicle, a third radius of curvature obtained by multiplying a first weight constant to the first radius of curvature and a second weight constant to the second radius of curvature and adding results of the multiplications, the first and second radius of curvatures being obtained at a same time point as a latest radius of curvature; and
a weight constant control unit which performsa process of changing the first weight constant and the second weight constant when the travel route of the own-vehicle is determined as having changed from a straight route to a curve and every time the third radius of curvature is calculated, wherein the first weight constant is increased and the second weight constant is decreased compared to those at a last calculation of the third radius of curvature by the weighted average unit, anda process of changing the first weight constant and the second weight constant when the travel route of the own-vehicle is determined as having changed from a curve to a straight route and every time the third radius of curvature is calculated, wherein the first weight constant is decreased and the second weight constant is increased compared to those at the last calculation of the third radius of curvature by the weighted average unit.
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Abstract
Provided is a travel route estimation device capable of accurately estimating, without excessively increasing communication load of the device, a shape of a travel route even when one'"'"'s own-vehicle is traveling on a travel route that does not have any objects installed on the route. A calculation section calculates and successively stores a radius of curvature of the travel route based on a yaw rate detected by a yaw rate detection section and on a traveling velocity detected by a velocity detection section. When conducting a filtering process for reducing variation of the calculate radius of curvature, the calculation section selects a filtering constant for multiplying the stored radius of curvature in accordance with the type of the travel route of the own-vehicle, and generates information representing a radius of curvature obtained by conducting at least one filtering process by using the selected filtering constant.
56 Citations
8 Claims
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1. A travel route estimation device comprising:
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a displacement velocity detection unit which detects a displacement velocity of one'"'"'s own-vehicle over a travel route surface; a radius-of-curvature calculation unit which calculates, based on the displacement velocity, a plurality of radius of curvatures of a travel route of the own-vehicle; a filtering process unit which conducts a filtering process on radius of curvatures up to a radius of curvature preceding a latest estimated radius of curvature by a predetermined number, among the plurality of radius of curvatures calculated by the radius-of-curvature calculation unit, and outputs a first radius of curvature and a second radius of curvature which is a value obtained at a same point as the first radius of curvature and has a lower responsivity to a change in the radius of curvature of the travel route of the own-vehicle than the first radius of curvature; a weighted average unit which calculates, as a radius of curvature to be output to a safety apparatus of the own-vehicle, a third radius of curvature obtained by multiplying a first weight constant to the first radius of curvature and a second weight constant to the second radius of curvature and adding results of the multiplications, the first and second radius of curvatures being obtained at a same time point as a latest radius of curvature; and a weight constant control unit which performs a process of changing the first weight constant and the second weight constant when the travel route of the own-vehicle is determined as having changed from a straight route to a curve and every time the third radius of curvature is calculated, wherein the first weight constant is increased and the second weight constant is decreased compared to those at a last calculation of the third radius of curvature by the weighted average unit, and a process of changing the first weight constant and the second weight constant when the travel route of the own-vehicle is determined as having changed from a curve to a straight route and every time the third radius of curvature is calculated, wherein the first weight constant is decreased and the second weight constant is increased compared to those at the last calculation of the third radius of curvature by the weighted average unit. - View Dependent Claims (2, 3, 4, 5, 6)
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7. A travel route estimation method implemented by a processor of a travel route estimation device, the method comprising:
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a displacement velocity detection step of detecting a displacement velocity of one'"'"'s own-vehicle over a travel route surface; a radius-of-curvature calculation step of calculating, based on the displacement velocity, a plurality of radius of curvatures of a travel route of the own-vehicle; a filtering process step of conducting a filtering process on radius of curvatures up to a radius of curvature preceding a latest estimated radius of curvature by a predetermined number, among the plurality of radius of curvatures calculated by the radius-of-curvature calculation step, and outputting a first radius of curvature and a second radius of curvature which is a value obtained at a same point as the first radius of curvature and has a lower responsivity to a change in the radius of curvature of the travel route of the own-vehicle than the first radius of curvature; a weighted average step of calculating, as a radius of curvature to be output to a safety apparatus of the own-vehicle, a third radius of curvature obtained by multiplying a first weight constant to the first radius of curvature and a second weight constant to the second radius of curvature and adding results of the multiplications, the first and second radius of curvatures being obtained at a same time point as a latest radius of curvature; and a weight constant control step of performing a process of changing the first weight constant and the second weight constant when the travel route of the own-vehicle is determined as having changed from a straight route to a curve and every time the third radius of curvature is calculated, wherein the first weight constant is increased and the second weight constant is decreased compared to those at a last calculation of the third radius of curvature by the weighted average step, and a process of changing the first weight constant and the second weight constant when the travel route of the own-vehicle is determined as having changed from a curve to a straight route and every time the third radius of curvature is calculated, wherein the first weight constant is decreased and the second weight constant is increased compared to those at the last calculation of the third radius of curvature by the weighted average step. - View Dependent Claims (8)
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Specification