Method for determining the kinematic state of an object, by evaluating sensor measured values
First Claim
1. A method for determining a kinematic state of an object, including at least one of position, velocity and acceleration of the object, said method comprising:
- a sensor making a sequence of discrete polar measurements with respect to said object, said polar measurements including as polar measurement variables, range and azimuth measurements from said sensor to said object;
converting the polar measurements to Cartesian coordinates by conversion of the polar measurement variables range and azimuth;
scaling the Cartesian coordinates to Cartesian pseudo-measurements using a scaling factor β
which is determined as a function of measured range;
determining associated nominal pseudo-measurement error variance matrices, each comprising specific nominal pseudo-measurement error variances (R2m) in a range direction and transversely thereto (C2m), as a function of the measured range; and
based on the Cartesian pseudo-measurements and the associated nominal pseudo-measurement error variance matrices, an estimation unit estimating the kinematic state of the object, with an estimated variance {circumflex over (σ
)}2cross being determined transversely with respect to the range direction;
wherein,the scaling factor β
is determined in the estimation device such that no systematic error results for a position estimate comprising n>
1 measurements; and
the nominal pseudo-measurement error variance R2m in the range direction is determined in the estimation device as a function of the nominal pseudo-measurement error variance C2m transversely to the range direction, or such that the variance {circumflex over (σ
)}2cross which is estimated after the processing of n>
1 measurements, transversely with respect to the range direction, on average matches the actual variance {circumflex over (σ
)}2cross of the estimated error transversely with respect to the range direction.
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Accused Products
Abstract
In a method for determining the kinematic state of an object by evaluating a sequence of discrete polar measured values of a sensor, the polar measurements rm, αm are converted to Cartesian coordinates and subsequently scaled to Cartesian pseudo-measurements using a scaling factor β calculated as a function of measured range rm. Associated pseudo-measurement error variance matrices are determined, each comprising nominal measurement error variances in the range direction R2m and transversely thereto C2m as a function of the measured range rm. The state of the object is estimated, with an estimated variance {circumflex over (σ)}2cross being determined transversely with respect to the range direction in an estimation device, based on the Cartesian pseudo-measurements and the pseudo-measurement error variance matrices. The scaling factor β is chosen such that no systematic error results for a position estimate comprising n>1 measurements; and the nominal pseudo-measurement error variance R2m in the range direction is calculated as a function of the nominal pseudo-measurement error variance C2m transversely thereto or conversely such that the variance {circumflex over (σ)}2cross which is estimated after processing of n>1 measurements, transversely with respect to the range direction, on average matches the actual variance {circumflex over (σ)}2cross of the estimated error transversely with respect to the range direction.
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Citations
6 Claims
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1. A method for determining a kinematic state of an object, including at least one of position, velocity and acceleration of the object, said method comprising:
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a sensor making a sequence of discrete polar measurements with respect to said object, said polar measurements including as polar measurement variables, range and azimuth measurements from said sensor to said object; converting the polar measurements to Cartesian coordinates by conversion of the polar measurement variables range and azimuth; scaling the Cartesian coordinates to Cartesian pseudo-measurements using a scaling factor β
which is determined as a function of measured range;determining associated nominal pseudo-measurement error variance matrices, each comprising specific nominal pseudo-measurement error variances (R2m) in a range direction and transversely thereto (C2m), as a function of the measured range; and based on the Cartesian pseudo-measurements and the associated nominal pseudo-measurement error variance matrices, an estimation unit estimating the kinematic state of the object, with an estimated variance {circumflex over (σ
)}2cross being determined transversely with respect to the range direction;
wherein,the scaling factor β
is determined in the estimation device such that no systematic error results for a position estimate comprising n>
1 measurements; andthe nominal pseudo-measurement error variance R2m in the range direction is determined in the estimation device as a function of the nominal pseudo-measurement error variance C2m transversely to the range direction, or such that the variance {circumflex over (σ
)}2cross which is estimated after the processing of n>
1 measurements, transversely with respect to the range direction, on average matches the actual variance {circumflex over (σ
)}2cross of the estimated error transversely with respect to the range direction. - View Dependent Claims (2, 3, 4, 5, 6)
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Specification