在ROS catkin工作区中定义和使用Python类

Question

I am running ROS Indigo. I have what should be a simple problem: I have a utility class in my package that I want to be callable from our scripts. It only needs to be called within our own package; I don't need it to be available to other ROS packages.

I defined a class named HandControl in a file HandControl.py. All my attempts to import it, or use it without importing, fail. Where in the catkin workspace do I put it -- the root of the package, or in scripts? Do I need __init.py__ anywhere (I have tried several places)?

Answer 1

It is a good practice to follow the standards of Python and ROS here. Scripts are typically placed in /script directory and they should not be imported into other python scripts. Reusable python code is an indication of a python module. Python modules should be placed in /src/package_name and there you should create __init__.py as well. This module will be available everywhere in your catkin workspace. There is a good chance this structure will help you in the future to structure things, even though you may not seem to need it at the moment. Project typically grow and following guidelines helps to maintain good code. For more specific details checkout this python doc .

Answer 2

Erica,

please see this school project, which was written in Python and run on ROS Indigo. If you'd look in the /scripts folder, you can see an example of a custom class that is being called from other scripts. If you'd look into the launch files in /launch you can see an example of configuring the ROS nodes - maybe that is your problem.