Trying to communicate with robot in gazebo

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Dear Peter, thanks for the information. But actually, i am using OpenSOT software, which is a kind of cartesian planar as MoveIT. I need to do it. Because my thesis revolve around this OpenSOT. Can you please tell, how to do it. The planning solution is in the form of sensor_msgs/JointState. I can see the movement in rviz but in order to command the robot in Gazebo, i have to write this node. I will be thankful to you if you can help to do it.

Thank You advance.

Okay, I think I can see what you're trying to do. But I still need to clarify a joint state message is not a trajectory. A sequence of JointState messages through time can be interpreted as a trajectory, but you'd need to receive all the JointState messages for the arm movement, then combine them into a single trajectory message at the end and then publish the trajectory. So you cannot control the robot in Gazebo so it matches the preview in RVIZ using Trajectory messages.

It sounds as though the OpenSOT planner may not be using the ROS messages in the way they were intended, have you checked that it definitely doesn't produce a trajectory message on any other topic?

Dear Peter, from open SOT i am getting the position, velocity and effort for each joint in a single message like trajectory. Now i want to store it in a variable, and then publish it onto trajectory_msg topic for commanding the robot.

i have modified the code little bit; but is giving me error;

using namespace std;

trajectory_msgs::JointTrajectory JT;

ros::Publisher joint_pub = n.advertise<trajectory_msgs::jointtrajectory>("/panda/panda_arm_controller/command", 1, true);

//sensor_msgs::JointState JS;

void jointStateCallback(const sensor_msgs::JointState msg) {

trajectory_msgs::JointTrajectoryPoint JTP; // goes inside JT

JTP.positions = msg.position;
JTP.velocities = msg.velocity;
//JTP.accelerations = 0.1;
JTP.effort = msg.effort;

JT.joint_names.clear();
JT.joint_names.push_back("panda_joint_x");
JT.joint_names.push_back("panda_joint_y");
JT.joint_names.push_back("panda_joint_theta");
JT.joint_names.push_back("schunk_pw70_joint_pan");
.......

This is the output from the OpenSoT as sensor_msgs;

name: [panda_joint_x, panda_joint_y, panda_joint_theta, schunk_pw70_joint_pan, schunk_pw70_joint_tilt, panda_joint_1, panda_joint_2, panda_joint_3, panda_joint_4, panda_joint_5, panda_joint_6, panda_joint_7] position: [0.0, 0.0, 0.0, 0.0, 0.0, 0.20188842702340157, -0.2322311127130126, 0.06608537389950296, -0.41370386826829264, -0.14111314933689595, 0.6262688313112118, -1.7655084865157107] velocity: [0.0, 0.0, 0.0, 0.0, 0.0, -1.7657115715683645e-05, -2.532212576461529e-08, 4.4130291118976247e-07, 3.948027972404961e-07, 1.7127194418392722e-05, 2.7396514534677685e-07, -3.011904900997595e-06]

effort: []

Now i want to read these values from this topic "Catersian/solution" and publishes it on the "/panda/panda_arm_controller/command". I hope i explain you clearly.

A single trajectory message contains the whole movement, you cannot control an arm by sending many short trajectory messages one after another. You'd have to record all the JointState messages and combine them into a single trajectory, then send that single trajectory to your robot.

Can you see; am i doing right?

using namespace std;

sensor_msgs::JointState JS;

float joint_position[12] = {0,0,0,0,0,0,0,0,0,0,0,0}; float joint_velocity[12] = {0,0,0,0,0,0,0,0,0,0,0,0}; float joint_acceleration = 0.01; float joint_effort = 0.001;

void jointStateCallback(const sensor_msgs::JointState msg) {

joint_position[0]=msg.position[0]; joint_position[1]=msg.position[1]; joint_position[2]=msg.position[2]; joint_position[3]=msg.position[3]; joint_position[4]=msg.position[4]; joint_position[5]=msg.position[5]; joint_position[6]=msg.position[6]; joint_position[7]=msg.position[7]; joint_position[8]=msg.position[8]; joint_position[9]=msg.position[9]; joint_position[10]=msg.position[10]; joint_position[11]=msg.position[11]; joint_velocity[0]=msg.velocity[0]; joint_velocity[1]=msg.velocity[1]; joint_velocity[2]=msg.velocity[2]; joint_velocity[3]=msg.velocity[3]; joint_velocity[4]=msg.velocity[4]; joint_velocity[5]=msg.velocity[5];

Dear Peter, i want to read the data from topic " Cartesian?interface" but i am running the code, it showing me zeros only. Can you please guide me where i am making eroor.

Thank You