User Manual

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Note: If the rospack depends hps_camera is executed, the following error occurs (when the ros*

command is used, an error occurs, it may be that the workspace has failed, it can be re-validated,

or it can be written into the ros environment variable) Go back to the workspace directory and

execute source devel/setup.bash again to make the workspace work, as shown in the following

figure:

2.4.3 Create ROS message msg and service srv

The msg file is a simple text file that describes the fields of messages in ROS and is used to

generate source code for different languages for messages.

The srv file describes a service consisting of two parts, a request and a service.

Tip: A msg file or a srv file is equivalent to a structure, so you can compare the provided api.h.

There are five data types in the depth camera data return package. Each data type is a structure,

that is, When writing msg files, you can nest them.

、

Create ROS message msg

(1) In the created package, create a message msg directory to store the msg file. Enter cd

~/HPS3D_SDK_ROS_Demo/src/hps_camera/ in the terminal, go to the package directory; enter

mkdir msg, create the msg directory; type echo "uint16 distance_average" > msg/distance.msg,

create the distance.msg file, and write the average distance variable. As shown below: