Arm not moving with Cartesian pose

[saurabhbansal90]

I am having a 3 DOF robotic arm. For this arm, I am using IK-Fast motion planner for its movement.

I am using below code to move the arm to different points:

`#include <moveit/move_group_interface/move_group_interface.h>
#include <moveit/planning_scene_interface/planning_scene_interface.h>
#include <moveit_msgs/DisplayRobotState.h>
#include <moveit_msgs/DisplayTrajectory.h>
#include <moveit_msgs/AttachedCollisionObject.h>
#include <moveit_msgs/CollisionObject.h>
int main(int argc, char** argv)
{
ros::init(argc, argv, "move_group_interface_tutorial");
ros::NodeHandle node_handle;
ros::AsyncSpinner spinner(1);
spinner.start();

moveit::planning_interface::MoveGroupInterface move_group("arm");
moveit::planning_interface::PlanningSceneInterface planning_scene_interface;
const robot_state::JointModelGroup *joint_model_group = move_group.getCurrentState()->getJointModelGroup("arm");

ROS_INFO_NAMED("tutorial", "Reference frame: %s", move_group.getPlanningFrame().c_str());
ROS_INFO_NAMED("tutorial", "End effector link: %s", move_group.getEndEffectorLink().c_str());

moveit::planning_interface::MoveGroupInterface::Plan my_plan;

/* Move Code: With xyz positions */
geometry_msgs::PoseStamped target_pose1;
target_pose1 = move_group.getCurrentPose(move_group.getEndEffectorLink());
//target_pose1.orientation.w = 1.0;
target_pose1.pose.position.y = 0.01;
//target_pose1.position.y = 0.0;
//target_pose1.position.z = 0.58;
move_group.setPoseTarget(target_pose1);

/* Move Code: With Joint positions
moveit::core::RobotStatePtr current_state = move_group.getCurrentState();
std::vector joint_group_positions;
current_state->copyJointGroupPositions(joint_model_group, joint_group_positions);
for(std::vector::iterator it = joint_group_positions.begin(); it != joint_group_positions.end(); it++)
ROS_INFO("Joint position: %lf", *it);
joint_group_positions[0] = -0.5;
move_group.setJointValueTarget(joint_group_positions);
*/
move_group.plan(my_plan);
move_group.move();
return 0;
}`

Here my problem is that, I am not able to move the arm with setting the xyz pose. I am able to move it with setting the joints, as shown in commented part of the code. I am also able to move it with RViz goal settings.
And I am getting below errors:
[ WARN] [1528544186.050648987]: Fail: ABORTED: No motion plan found. No execution attempted. [ INFO] [1528544191.086188354]: ABORTED: No motion plan found. No execution attempted.
and
[ INFO] [1528544186.058533344]: Planner configuration 'arm' will use planner 'geometric::RRTConnect'. Additional configuration parameters will be set when the planner is constructed. Debug: RRTConnect: Planner range detected to be 0.706318 Info: RRTConnect: Starting planning with 1 states already in datastructure Debug: RRTConnect: Waiting for goal region samples ... Debug: Beginning sampling thread computation Error: RRTConnect: Unable to sample any valid states for goal tree at line 215 in /tmp/binarydeb/ros-kinetic-ompl-1.2.1/src/ompl/geometric/planners/rrt/src/RRTConnect.cpp Info: RRTConnect: Created 1 states (1 start + 0 goal) Info: No solution found after 5.007490 seconds Debug: Attempting to stop goal sampling thread... Debug: Stopped goal sampling thread after 0 sampling attempts

I am not able to find the solution for this. Please let me know what should be the problem for this.

Saurabh

[Ridhwanluthra]

is target_pose1.pose.position.y = 0.01; is an allowed state? i.e is it within the joint limits specified in the urdf?

[saurabhbansal90]

Hello Ridhwan,

Thanks for your response.
Yes y=0.01 is an allowed state. And even if I didn't change y, so if target_pose1 is exactly same as current pose, then also it is giving error (but in that case error is target and present position are same).

But I tried same thing with my other robots in simulation, it doesn't give error for target_pose same as current one.
But if there is really some issue in MoveIt, there should not be any movement with setting joint states, but with setting joint states by MoveIt, it moves without any error.

[Ridhwanluthra]

Please share your robots configuration and your systems description including the rosdistro and install type of moveit, like source or binary. if source, what commit tag.

[saurabhbansal90]

Hello Ridhwan,

Please find my launch files and urdf for my robot.
And also please find the below details:

• ROS version: Kinetic (unversioned), please let me know if its a problem
• MoveIt! version: 0.9.11
• I installed both ROS and MoveIt from binary only

all_files.zip

Please let me know, if any other information is needed.

Saurabh

[saurabhbansal90]

Hello Ridhwan, is the information given is enough to work on the issue.
Can you please let me know if some more information is needed or if you figured out some problem in my code.

Thanks,
Saurabh

[felixvd]

Have you solved this issue? If yes, can you post your results or close this?

In general, if you do not set a very high orientation tolerance, you might not have much luck using the cartesian planner with a 3-DOF robot.