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,
      boost::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_;

  boost::shared_ptr<controller_manager::ControllerManager> controller_manager_;

  boost::shared_ptr<hardware_interface::RobotHW> hardware_interface_;

};  // end class

}  // namespace