copy

Copy lidar SLAM object

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Syntax

newSlamObj = copy(slamObj)

Description

newSlamObj = copy(slamObj) creates a deep copy of slamObj with the same properties. Any changes made to newSlamObj are not reflected in slamObj.

example

Examples

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Open Live Script

Create a lidarSLAM object.

slamObj = lidarSLAM
slamObj = 
  lidarSLAM with properties:

                  PoseGraph: [1×1 poseGraph]
              MapResolution: 20
              MaxLidarRange: 8
            OptimizationFcn: @optimizePoseGraph
       LoopClosureThreshold: 100
    LoopClosureSearchRadius: 8
     LoopClosureMaxAttempts: 1
    LoopClosureAutoRollback: 1
       OptimizationInterval: 1
          MovementThreshold: [0 0]
     ScanRegistrationMethod: 'BranchAndBound'
     TranslationSearchRange: [4 4]
        RotationSearchRange: 1.5708

Create a copy of the lidar SLAM object.

slamObjNew = copy(slamObj)
slamObjNew = 
  lidarSLAM with properties:

                  PoseGraph: [1×1 poseGraph]
              MapResolution: 20
              MaxLidarRange: 8
            OptimizationFcn: @optimizePoseGraph
       LoopClosureThreshold: 100
    LoopClosureSearchRadius: 8
     LoopClosureMaxAttempts: 1
    LoopClosureAutoRollback: 1
       OptimizationInterval: 1
          MovementThreshold: [0 0]
     ScanRegistrationMethod: 'BranchAndBound'
     TranslationSearchRange: [4 4]
        RotationSearchRange: 1.5708
Open Live Script

Load laser scan data from a file.

load("offlineSlamData.mat");

To set up the SLAM algorithm:

  1. Specify the lidar range, map resolution, loop closure threshold, and search radius.

  2. Tune these parameters for your specific robot and environment.

  3. Create the lidarSLAM object with these parameters.

maxLidarRange = 8;
mapResolution = 20;
slamObj = lidarSLAM(mapResolution,maxLidarRange);
slamObj.LoopClosureThreshold = 210;  
slamObj.LoopClosureSearchRadius = 8;

Add scans iteratively to the SLAM object.

for i = 1:numel(scans)
    addScan(slamObj,scans{i});
end

Create a copy of the SLAM object. Display the underlying pose graph of the SLAM object.

slamObj2 = copy(slamObj);
slamObj2.PoseGraph
ans = 
  poseGraph with properties:

               NumNodes: 71
               NumEdges: 83
    NumLoopClosureEdges: 13
     LoopClosureEdgeIDs: [31 36 63 65 67 69 71 73 75 77 79 81 83]
        LandmarkNodeIDs: [1×0 double]

Remove the first two loop closures by specifying their edge IDs.

lcEdgeIDs = slamObj2.PoseGraph.LoopClosureEdgeIDs(1:2);
removeLoopClosures(slamObj2,lcEdgeIDs)

Plot the pose graphs of the SLAM object before and after removing the loop closures.

subplot(2,1,1)
show(slamObj.PoseGraph);
subplot(2,1,2)
show(slamObj2.PoseGraph);

Figure contains 2 axes objects. Axes object 1 with xlabel X, ylabel Y contains 42 objects of type line, text. One or more of the lines displays its values using only markers Axes object 2 with xlabel X, ylabel Y contains 36 objects of type line, text. One or more of the lines displays its values using only markers

Input Arguments

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Lidar SLAM object, specified as a lidarSLAM object. The object contains the SLAM algorithm parameters, sensor data, and underlying pose graph used to build the map.

Output Arguments

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Lidar SLAM object, returned as a lidarSLAM object.

Extended Capabilities

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Version History

Introduced in R2019b

See Also

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