ROS Read Scan, ROS 2 Read Scan

Extract scan data from ROS or ROS 2 laser scan message

• Library:

• ROS Toolbox / ROS

  ROS Toolbox / ROS 2

• 
• 

×

Description

The Read Scan block extracts range, scan and intensity data from a ROS or ROS 2 laser scan message. You can select the message parameters of a topic active on a live ROS or ROS 2 network, or specify the message parameters separately. The input messages are specified as a nonvirtual bus. Use the ROS Subscribe or the ROS 2 Subscribe block to receive a message from the network and input the message to the Read Scan block. For ROS and ROS 2 models, you must use the blocks in the respective ROS and ROS 2 library.

Ports

Input

Msg — ROS or ROS 2 laser scan message

nonvirtual bus

ROS 2 laser scan message, specified as a nonvirtual bus. You can use the ROS Subscribe or the ROS 2 Subscribe blocks to get a message from the network.

Data Types: bus

Output

Ranges — Range values for each point

array

Range values for each point in the scan, returned as an array of length M.

Data Types: single

Angles — Angle values for each point

array

Angle values for each point in the scan, returned as an array of length M.

Dependencies

Enable Show Angles output port parameter.

Data Types: single

Intensities — Intensity value for each point

array

Intensity values for each point in the scan, returned as an array of length M.

Dependencies

Enable Show Intensities output port parameter.

Data Types: single

ErrorCode — Error code for message parsing

scalar

Error code for message parsing, returned as a scalar. The error code values are:

• 0 — Successfully parsed the laser scan message.

• 1 — The Data field of the laser scan message was truncated.

Dependencies

Enable Show ErrorCode output port parameter.

Data Types: uint8

Parameters

Maximum array length — Maximum length of the laser scan array

100 (default) | positive scalar

Maximum length of the laser scan array, specified as a positive scalar.

Select Configure using ROS... to set this parameter automatically using an active topic on a ROS or ROS 2 network. You must be connected to the network.

Show Angles output port — RGB port toggle

off (default) | on

Select this parameter to enable the Angles port. If you enable this parameter, the message must contain RGB data or the block returns an error code.

Show Intensity output port — Intensity port toggle

off (default) | on

Select this parameter to enable the Intensity port. If you enable this parameter, the message must contain intensity data or the block returns an error code.

Show ErrorCode output port — ErrorCode port toggle

on (default) | off

Select this parameter to enable the ErrorCode port and monitor errors.

Output variable-size signals — Variable-size signal output toggle

off (default) | on

Toggle whether to output a variable-size signal. Use variable-sized signals only if you expect the image size to change over time. For more information about variable-size signals, see Variable-Size Signal Basics (Simulink).

Model Examples

Read A ROS Scan Message In Simulink®

Read in a laser scan message from a ROS network. Calculate the points in Cartesian coordinates and visualize with a 2D plot.

Open Script

Extended Capabilities

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

Version History

Introduced in R2022a