transformScan

Create a lidarScan object. Specify the ranges and angles as vectors.

refRanges = 5*ones(1,300);
refAngles = linspace(-pi/2,pi/2,300);
refScan = lidarScan(refRanges,refAngles);

Translate the laser scan by an [x y] offset of (0.5,0.2).

transformedScan = transformScan(refScan,[0.5 0.2 0]);

Rotate the laser scan by 20 degrees.

rotateScan = transformScan(refScan,[0,0,deg2rad(20)]);

Use the matchScans function to find the relative transformation between two lidar scans. Then, transform the second scan into the coordinate frame of the first scan.

Load a pair of lidar scans as a pair of lidarScan objects. They are two scans of the same scene with a change in relative pose.

load tb3_scanPair.mat
plot(s1)
hold on
plot(s2)
hold off

The relative pose is estimated from an odometry sensor and provided as a variable, initGuess, as [x y theta].

disp(initGuess)

   -0.7000    0.1500   -0.3254

Use scan matching to find the relative pose between the two laser scans and specify the initial guess for the pose.

pose = matchScans(s2,s1,"InitialPose",initGuess);
disp(pose)

   -0.7213    0.1160   -0.2854

Transform the second scan to the coordinate frame of the first scan. Plot the two scans to see that they now overlap.

s2Transformed = transformScan(s2,pose);
plot(s1)
hold on
plot(s2Transformed)
hold off