title: publishing trajectory_msgs/jointtrajectory msgs
body: <p>When i set the position and velocities of the joints in the trajectory msgs i got an error: \</p>
  
  <pre><code>[state_publisher-2] process has died [pid 13362, exit code -11, cmd /home/rob/catkin_ws/devel/lib/r2d2/state_publisher __name:=state_publisher __log:=/home/rob/.ros/log/9980f352-cf74-11e6-8644-d4c9efe8bd37/state_publisher-2.log].
  log file: /home/rob/.ros/log/9980f352-cf74-11e6-8644-d4c9efe8bd37/state_publisher-2*.log
  </code></pre>
  
  <p>My ros node to send geometry_msgs is:</p>
  
  <pre><code>#include &lt;string&gt;
      #include &lt;ros/ros.h&gt;
      #include &lt;sensor_msgs/JointState.h&gt;
      #include &lt;tf/transform_broadcaster.h&gt;
      #include &lt;trajectory_msgs/JointTrajectory.h&gt;
      #include &lt;vector&gt;
      int main(int argc, char** argv) {
          ros::init(argc, argv, "state_publisher");
          ros::NodeHandle n;
          ros::Publisher joint_pub = n.advertise&lt;trajectory_ms
  
  gs::JointTrajectory&gt;("set_joint_trajectory", 1);
     ros::Rate loop_rate(30);
  
     const double degree = M_PI/180;
  
     // robot state
     double tilt = 0, tinc = degree, swivel=0, angle=0, height=0, hinc=0.005;
  
     // message declarations
     trajectory_msgs::JointTrajectory joint_state;
     std::vector&lt;trajectory_msgs::JointTrajectoryPoint&gt; points_n(3);
     points_n[0].positions[0] = 1; points_n[0].velocities[0]=10;
     while (ros::ok()) {
         //update joint_state
         joint_state.header.stamp = ros::Time::now();
         joint_state.joint_names.resize(3);
         joint_state.points.resize(3);
  
         joint_state.joint_names[0] ="swivel";
         joint_state.points[0] = points_n[0];
         joint_state.joint_names[1] ="tilt";
         joint_state.points[1] = points_n[1];
         joint_state.joint_names[2] ="periscope";
         joint_state.points[2] = points_n[2];
  
  
         joint_pub.publish(joint_state);
  
  
  
         // This will adjust as needed per iteration
         loop_rate.sleep();
     }
  
  
     return 0;
     }
  </code></pre>
  
  <p>Here when i donot set the position and velocity value it runs without error and when i run <code>rostopic echo /set_joint_trajectory</code> i can clearly see the outputs as all the parameters of points is 0. I also tried below program but it published nothing:</p>
  
  <pre><code> #include &lt;string&gt;
      #include &lt;ros/ros.h&gt;
      #include &lt;sensor_msgs/JointState.h&gt;
      #include &lt;tf/transform_broadcaster.h&gt;
      #include &lt;trajectory_msgs/JointTrajectory.h&gt;
      #include &lt;vector&gt;
      int main(int argc, char** argv) {
          ros::init(argc, argv, "state_publisher");
          ros::NodeHandle n;
          ros::Publisher joint_pub = n.advertise&lt;trajectory_msgs::JointTrajectory&gt;("set_joint_trajectory", 1);
  
          trajectory_msgs::JointTrajectory joint_state;
  
             joint_state.header.stamp = ros::Time::now();
             joint_state.header.frame_id = "camera_link";
             joint_state.joint_names.resize(3);
             joint_state.points.resize(3);
  
             joint_state.joint_names[0] ="swivel";
             joint_state.joint_names[1] ="tilt";
             joint_state.joint_names[2] ="periscope";
  
             size_t size = 2;
             for(size_t i=0;i&lt;=size;i++) {
                trajectory_msgs::JointTrajectoryPoint points_n;
                int j = i%3;
                points_n.positions.push_back(j);
                points_n.positions.push_back(j+1);
                points_n.positions.push_back(j*2);
                joint_state.points.push_back(points_n);
                joint_state.points[i].time_from_start = ros::Duration(0.01);
             }
             joint_pub.publish(joint_state);
             ros::spinOnce();
         return 0;
     }
  </code></pre>