follow_joint_trajectory_client.cpp

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/*
 * follow_joint_trajectory_client.cpp
 *
 *  Created on: 06.11.2011
 *      Author: martin
 */

#include <katana_tutorials/follow_joint_trajectory_client.h>

namespace katana_tutorials
{

FollowJointTrajectoryClient::FollowJointTrajectoryClient() :
    traj_client_("/katana_arm_controller/follow_joint_trajectory", true), got_joint_state_(false), spinner_(1)
{
  joint_names_.push_back("katana_motor1_pan_joint");
  joint_names_.push_back("katana_motor2_lift_joint");
  joint_names_.push_back("katana_motor3_lift_joint");
  joint_names_.push_back("katana_motor4_lift_joint");
  joint_names_.push_back("katana_motor5_wrist_roll_joint");

  joint_state_sub_ = nh_.subscribe("/joint_states", 1, &FollowJointTrajectoryClient::jointStateCB, this);
  spinner_.start();

  // wait for action server to come up
  while (!traj_client_.waitForServer(ros::Duration(5.0)))
  {
    ROS_INFO("Waiting for the follow_joint_trajectory server");
  }
}

FollowJointTrajectoryClient::~FollowJointTrajectoryClient()
{
}

void FollowJointTrajectoryClient::jointStateCB(const sensor_msgs::JointState::ConstPtr &msg)
{
  std::vector<double> ordered_js;

  ordered_js.resize(joint_names_.size());

  for (size_t i = 0; i < joint_names_.size(); ++i)
  {
    bool found = false;
    for (size_t j = 0; j < msg->name.size(); ++j)
    {
      if (joint_names_[i] == msg->name[j])
      {
        ordered_js[i] = msg->position[j];
        found = true;
        break;
      }
    }
    if (!found)
      return;
  }

  ROS_INFO_ONCE("Got joint state!");
  current_joint_state_ = ordered_js;
  got_joint_state_ = true;
}

void FollowJointTrajectoryClient::startTrajectory(control_msgs::FollowJointTrajectoryGoal goal)
{
  // When to start the trajectory: 1s from now
  goal.trajectory.header.stamp = ros::Time::now() + ros::Duration(1.0);
  traj_client_.sendGoal(goal);
}

control_msgs::FollowJointTrajectoryGoal FollowJointTrajectoryClient::makeArmUpTrajectory()
{
  const size_t NUM_TRAJ_POINTS = 4;
  const size_t NUM_JOINTS = 5;

  // positions after calibration
  std::vector<double> calibration_positions(NUM_JOINTS);
  calibration_positions[0] = -2.96;
  calibration_positions[1] = 2.14;
  calibration_positions[2] = -2.16;
  calibration_positions[3] = -1.97;
  calibration_positions[4] = -2.93;

  // arm pointing straight up
  std::vector<double> straight_up_positions(NUM_JOINTS);
  straight_up_positions[0] = 0.0;
  straight_up_positions[1] = 1.57;
  straight_up_positions[2] = 0.0;
  straight_up_positions[3] = 0.0;
  straight_up_positions[4] = 0.0;

  trajectory_msgs::JointTrajectory trajectory;

  for (ros::Rate r = ros::Rate(10); !got_joint_state_; r.sleep())
  {
    ROS_DEBUG("waiting for joint state...");

    if (!ros::ok())
      exit(-1);
  }

  // First, the joint names, which apply to all waypoints
  trajectory.joint_names = joint_names_;

  trajectory.points.resize(NUM_TRAJ_POINTS);

  // trajectory point:
  int ind = 0;
  trajectory.points[ind].time_from_start = ros::Duration(5 * ind);
  trajectory.points[ind].positions = current_joint_state_;

  // trajectory point:
  ind++;
  trajectory.points[ind].time_from_start = ros::Duration(5 * ind);
  trajectory.points[ind].positions = calibration_positions;

  // trajectory point:
  ind++;
  trajectory.points[ind].time_from_start = ros::Duration(5 * ind);
  trajectory.points[ind].positions = straight_up_positions;

  // trajectory point:
  ind++;
  trajectory.points[ind].time_from_start = ros::Duration(5 * ind);
  trajectory.points[ind].positions.resize(NUM_JOINTS);
  trajectory.points[ind].positions = calibration_positions;

  //  // all Velocities 0
  //  for (size_t i = 0; i < NUM_TRAJ_POINTS; ++i)
  //  {
  //    trajectory.points[i].velocities.resize(NUM_JOINTS);
  //    for (size_t j = 0; j < NUM_JOINTS; ++j)
  //    {
  //      trajectory.points[i].velocities[j] = 0.0;
  //    }
  //  }

  control_msgs::FollowJointTrajectoryGoal goal;
  goal.trajectory = trajectory;
  return goal;
}

actionlib::SimpleClientGoalState FollowJointTrajectoryClient::getState()
{
  return traj_client_.getState();
}

} /* namespace katana_tutorials */

int main(int argc, char** argv)
{
  // Init the ROS node
  ros::init(argc, argv, "follow_joint_trajectory_client");

  katana_tutorials::FollowJointTrajectoryClient arm;
  // Start the trajectory
  arm.startTrajectory(arm.makeArmUpTrajectory());
  // Wait for trajectory completion
  while (!arm.getState().isDone() && ros::ok())
  {
    usleep(50000);
  }
}