ncw000's profile - activity

You can write a gazebo plugin to send torque or velocity commands to each wheel and the steering joint. Possibly wrapping a simple PID controller around each controlled joint. An empty gazebo_plugin template has been provided for your convenience. Also, please take a look at the diffdrive example for reference on how to construct a plugin that sends velocity commands to individual joints.

Alternatively, if you are familiar with pr2_mechanism control stacks, you can use some predefined robot mechanism controllers to control your joints. A simple controlled joint example can be found in the single link example as shown here.

In Gazebo, Stage and real-world navigation initiating movement usually involves some variant of the "cmd_vel" topic, which is based on the "Twist" message format. For simple testing there are a number of nodes in different stacks (turtlebot, pr2) that provide this function using keyboard commands, usually named something like "keyboard_teleop".

I suggest that you examine the turtlesim tutorial (http://www.ros.org/wiki/ROS/Tutorials/UnderstandingTopics) for a good start. It uses "rosrun turtlesim turtle_teleop_key". Use rxgraph to inspect the topics/messages in your simulation and be prepared to remap topic names as required.

I'm trying to use the gazebo package to simulate a simple car-like robot moving around a field. Currently, I've been able to load a model of my robot into a simulation. However, I haven't had any luck understanding how to go about making the robot move via external commands (keyboard presses, etc.).

The documentation seems to gloss over this, or at least I can't find where it's described. How would I go about making a robot move in the a Gazebo simulation?