removeLandmark

Remove landmark from state vector

Since R2021b

Syntax

removeLandmark(slamObj,landmarkIndex)

Description

removeLandmark(slamObj,landmarkIndex) removes the landmarks at the specified indices landmarkIndex from the state vector, along with associated covariances from the state covariance matrix.

Examples

Remove Landmark from ekfSLAM Object

Specify the initial vehicle state.

initialState = [1; -2; 0.1];

Specify the initial landmark positions.

landmarkPosition = [15.8495; -12.9496;
                    25.2455; -15.4705;
                    37.5880;   3.1023;
                    16.5690;   2.7466];

Specify the initial vehicle state covariance.

initialStateCovar = diag([0.1*ones(1,3) 1.1*ones(1,8)]);

Create an ekfSLAM object with initial state and initial state covariance.

ekfSlamObj = ekfSLAM('State',[initialState; landmarkPosition], ...
                     'StateCovariance',initialStateCovar);
landmarkInfo(ekfSlamObj)

ans=4×3 table
    landmark number    landmark state index    landmark position
    _______________    ____________________    _________________

           1                  4     5           15.85    -12.95 
           2                  6     7          25.245    -15.47 
           3                  8     9          37.588    3.1023 
           4                 10    11          16.569    2.7466 

Create a deep copy of the ekfSLAM object.

newEkfSlamObj = copy(ekfSlamObj);

Specify the landmark number to be removed.

removeLandmark(newEkfSlamObj,3);
landmarkInfo(newEkfSlamObj)

ans=3×3 table
    landmark number    landmark state index    landmark position
    _______________    ____________________    _________________

           1                  4    5            15.85    -12.95 
           2                  6    7           25.245    -15.47 
           3                  8    9           16.569    2.7466 

Input Arguments

slamObj — EKF SLAM object

ekfSLAM object

EKF SLAM object, specified as an ekfSLAM object.

landmarkIndex — Indices of landmarks to remove

N-element column vector | N-by-2 matrix

Indices of the landmarks to remove, specified as an N-element column vector of landmark numbers in the state vector or an N-by-2 matrix of the exact positions of landmarks in the state vector. N is the number of landmarks to remove.

Data Types: single | double

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2021b