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Update robot platform body mesh



    updateMesh(platform,type,Name=Value) updates the body mesh of the robot platform with the specified mesh type and specifies additional options using one or more name-value pair arguments.


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    Create a robot scenario.

    scenario = robotScenario(UpdateRate=100,StopTime=1);

    Add the ground plane and a box as meshes.

    addMesh(scenario,"Plane",Size=[3 3],Color=[0.7 0.7 0.7]);
    addMesh(scenario,"Box",Size=[0.5 0.5 0.5],Position=[0 0 0.25], ...
            Color=[0 1 0])

    Create a waypoint trajectory for the robot platform using an ENU reference frame.

    waypoint = [0 -1 0; 1 0 0; -1 1 0; 0 -1 0];
    toa = linspace(0,1,length(waypoint));
    traj = waypointTrajectory("Waypoints",waypoint, ...
                              "TimeOfArrival",toa, ...

    Create a rigidBodyTree object of the TurtleBot 3 Waffle Pi robot with loadrobot.

    robotRBT = loadrobot("robotisTurtleBot3WafflePi");

    Create a robot platform with trajectory.

    platform = robotPlatform("TurtleBot",scenario, ...

    Set up platform mesh with the rigidBodyTree object.


    Create an INS sensor object and attach the sensor to the platform.

    ins = robotSensor("INS",platform,insSensor("RollAccuracy",0), ...

    Visualize the scenario.

    [ax,plotFrames] = show3D(scenario);
    axis equal
    hold on

    In a loop, step through the trajectory to output the position, orientation, velocity, acceleration, and angular velocity.

    count = 1;
    while ~isDone(traj)
        [Position(count,:),Orientation(count,:),Velocity(count,:), ...
         Acceleration(count,:),AngularVelocity(count,:)] = traj();
        count = count+1;

    Create a line plot for the trajectory. First create the plot with plot3, then manually modify the data source properties of the plot. This improves the performance of the plotting.

    trajPlot = plot3(nan,nan,nan,"Color",[1 1 1],"LineWidth",2);
    trajPlot.XDataSource = "Position(:,1)";
    trajPlot.YDataSource = "Position(:,2)";
    trajPlot.ZDataSource = "Position(:,3)";

    Set up the simulation. Then, iterate through the positions and show the scene each time the INS sensor updates. Advance the scene, move the robot platform, and update the sensors.

    for idx = 1:count-1
        % Read sensor readings.
        [isUpdated,insTimestamp(idx,1),sensorReadings(idx)] = read(ins);
        if isUpdated
            % Use fast update to move platform visualization frames.
            % Refresh all plot data and visualize.
            drawnow limitrate
        % Advance scenario simulation time and move platform.
        motion = [Position(idx,:),Velocity(idx,:),Acceleration(idx,:), ...
        % Update all sensors in the scene.
    hold off

    Figure contains an axes object. The axes object contains 28 objects of type patch, line.

    Input Arguments

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    Robot platform in the scenario, specified as a robotPlatform object.

    Type of mesh, specified as "Cuboid", "GroundVehicle", "RigidBodyTree", or "Custom".

    Data Types: char | string

    Name-Value Arguments

    Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

    Before R2021a, use commas to separate each name and value, and enclose Name in quotes.


    Relative mesh position in the body frame, specified as a vector of the form [x y z] in meters.

    Data Types: single | double

    Relative mesh orientation in the body frame, specified as a quaternion vector of the form [w x y z] or a quaternion object.

    Data Types: single | double

    Transformation of mesh relative to the body frame, specified as a 4-by-4 homogeneous transformation matrix. The matrix maps points in the platform mesh frame to points in the body frame.

    Data Types: single | double

    Robot platform body mesh color, specified as a RGB triplet, except for the rigid body mesh.

    Data Types: single | double

    Faces of the custom robot platform mesh, specified as an N-by-3 matrix of positive integers. The three elements in each row are the indices of the three points in the vertices forming a triangle face. N is the number of faces.

    Data Types: single | double

    Vertices of the custom robot platform mesh, specified as an N-by-3 matrix of real scalars. The first, second, and third element of each row represents the x-, y-, and z-position of each vertex, respectively. N is the number of vertices.

    Data Types: single | double

    Size of the cuboid robot platform mesh, specified as a vector of form [xlength ylength zlength] in meters.

    Data Types: single | double

    Scale of the ground vehicle robot platform mesh, specified as a scalar. Scale is unitless.

    Data Types: single | double

    Rigid body tree robot platform, specified as a rigidBodyTree object.

    Version History

    Introduced in R2022a

    See Also