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rosApplyTransform

Transform ROS and ROS 2 message entities into target frame

Since R2021a

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Syntax

tfentity = rosApplyTransform(tfmsg,entity)

Description

example

tfentity = rosApplyTransform(tfmsg,entity) applies the transformation represented by the 'TransformStamped' ROS or ROS 2 message to the input message structure entity.

This function determines the message type of entity and applies the appropriate transformation method to it.

Examples

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Open Live Script

Load ROS 2 point cloud and transformation messages.

load("ros2PtcloudMsgs.mat")

Visualize the point cloud message ptcloudMsg1.

rosPlot(ptcloudMsg1)
xlabel('X')
ylabel('Y')
zlabel('Z')
view([-180 80])

Note that the vertical direction in the point cloud is represented by the y-axis. You can transform the point cloud such that the z-axis represents the vertical direction. To accomplish this transformation, use the geometry_msgs/TransformStamped message, tfMsg, which contains a transform that rotates the points to a target frame that is 90 degrees in the clockwise direction along x-axis. Read the translation and rotation values from tfMsg using the rosReadTransform function.

[trans,rot] = rosReadTransform(tfMsg,OutputOption="pair")
trans = 3×1

     0
     0
     0


rot = 3×3

    1.0000         0         0
         0    0.0000    1.0000
         0   -1.0000    0.0000

Transform the point cloud to the target frame using the rosApplyTransform function. 

transformedPtcloudMsg = rosApplyTransform(tfMsg,ptcloudMsg1);

Visualize the transformed point cloud. Note that the vertical direction is now represented by the z-axis.

rosPlot(transformedPtcloudMsg)
view(-180,14)

Input Arguments

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Transformation message, specified as a TransformStamped ROS or ROS 2 message handle. The tfmsg is a ROS or ROS 2 message of type: 'geometry_msgs/TransformStamped'.

ROS or ROS 2 message, specified as a message structure.

Supported messages are:

  • geometry_msgs/PointStamped

  • sensor_msgs/PointCloud2

  • geometry_msgs/PoseStamped

  • geometry_msgs/QuaternionStamped

  • geometry_msgs/Vector3Stamped

Output Arguments

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Transformed ROS or ROS 2 message, returned as a message structure.

Extended Capabilities

Version History

Introduced in R2021a

See Also

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