generic_hw_control_loop.h

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/* Author: Dave Coleman
   Desc:   Example control loop for reading, updating, and writing commands to a hardware interface
   using MONOTOIC system time
*/
 
#include <time.h>
#include <controller_manager/controller_manager.h>
#include <hardware_interface/robot_hw.h>
 
namespace ros_control_boilerplate
{
// Used to convert seconds elapsed to nanoseconds
static const double BILLION = 1000000000.0;
 
class GenericHWControlLoop
{
public:
  GenericHWControlLoop(ros::NodeHandle& nh, std::shared_ptr<hardware_interface::RobotHW> hardware_interface);
 
  // Run the control loop (blocking)
  void run();
 
protected:
  // Update funcion called with loop_hz_ rate
  void update();
 
  // Startup and shutdown of the internal node inside a roscpp program
  ros::NodeHandle nh_;
 
  // Name of this class
  std::string name_ = "generic_hw_control_loop";
 
  // Settings
  ros::Duration desired_update_period_;
  double cycle_time_error_threshold_;
 
  // Timing
  ros::Duration elapsed_time_;
  double loop_hz_;
  struct timespec last_time_;
  struct timespec current_time_;
 
  std::shared_ptr<controller_manager::ControllerManager> controller_manager_;
 
  std::shared_ptr<hardware_interface::RobotHW> hardware_interface_;
 
};  // end class
 
}  // namespace ros_control_boilerplate