ROS Programming: Building Powerful Robots

pr2_controller_interface package

A basic ROS real-time controller must inherit a base class called pr2_controller_interface::Controller from this package. This base class contains four important functions: init() , start(), update(), and stop(). The basic structure of the Controller class is given as follows:

namespace pr2_controller_interface{  class Controller  {  public:    virtual bool init(pr2_mechanism_model::RobotState *robot,                     ros::NodeHandle &n);    virtual void starting();    virtual void update();    virtual void stopping();  };}

The workflow of the controller class is shown as follows.

Figure 1: Workflow of the controller