Error "Does your IK Solver support approximate IK ?" Moveit!

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Hello,

I am trying to write a script using move_group in order to move a custom robot in Moveit!. Using the joints as targets works perfectly, bu I have an issue when I try to target a pose, I get this error and the robot doesn't move :

Traceback (most recent call last):
File "/home/edith/catkin_ws/src/test_moveit/scripts/test.py", line 84, in <module> move_group.set_joint_value_target(pose_goal, "link_eff",True) File "/opt/ros/melodic/lib/python2.7/dist-packages/moveit_commander/move_group.py", line 219, in set_joint_value_target raise MoveItCommanderException("Error setting joint target. Does your IK solver support approximate IK?") moveit_commander.exception.MoveItCommanderException: Error setting joint target. Does your IK solver support approximate IK?

I use ROS melodic on a virtual machine with Ubuntu 18.04. My robot is a RRR robot (3DOF) and I use an IKFast solver, with parameter "TranslationXY2D".

I follow this tutorial : https://ros-planning.github.io/moveit...

Instead of

move_group.set_pose_target(pose_goal)

I used

move_group.set_joint_value_target(pose_goal, "link_eff",True)

Because this instruction allows IK approximate solutions with the boolean "True", unlike the other one : http://docs.ros.org/jade/api/moveit_c...

I know that the pose asked is reachable by the robot arm. At this point I don't know what else I can do, so thank to those who will take some time to answer ! Please find the URDF file and the concerned code. The URDF was generated from Solidworks with the exporter SW2URDF.

Code :

import sys import copy import rospy import moveit_commander import moveit_msgs.msg import math import time import std_msgs.msg import geometry_msgs.msg import moveit_commander.conversions

moveit_commander.roscpp_initialize(sys.argv)

rospy.init_node('move_group_python_interface_tutorial', anonymous=True)

robot = moveit_commander.RobotCommander()

group_name = "Arm" move_group = moveit_commander.MoveGroupCommander(group_name)

joint_goal = move_group.get_current_joint_values()

joint_goal[0] = 0.1744 joint_goal[1] = 0 joint_goal[2] = 0.3489 move_group.go(joint_goal, wait=True) move_group.stop()

pose_goal = move_group.get_current_pose()

time.sleep(0.5) pose_goal.pose.orientation.w = 1.0 time.sleep(0.5) pose_goal.pose.position.x = 0.671 time.sleep(0.5) pose_goal.pose.position.y = -0.667

move_group.set_joint_value_target(pose_goal, "link_eff",True)*

URDF :

<robot< p="">

name="swurdf">

<link< p="">

name="base_link">

<visual>

  <origin

    xyz="0 0 0"

    rpy="0 0 0" />

  <geometry>

    <mesh

      filename="package://swurdf/meshes/base_link.STL" />

  </geometry>

  <material

    name="">

    <color

      rgba="1 0 0 1" />

  </material>

</visual>

<collision>

  <origin

    xyz="0 0 0"

    rpy="0 0 0" />

  <geometry>

    <mesh

      filename="package://swurdf/meshes/base_link.STL" />

  </geometry>

</collision>

</link>

<link< p="">

name="link_1">

<inertial>

  <origin

    xyz="0.19475 -1.4951E-18 6.6018E-18"

    rpy="0 0 0" />

  <mass

    value="60" />

  <inertia

    ixx="0.0084601"

    ixy="3.2514E-18"

    ixz="5.5791E-19"

    iyy="0.062842"

    iyz="3.9785E-19"

    izz="0.069912" />

</inertial>

<visual>

  <origin

    xyz="0 0 0"

    rpy="0 0 0" />

  <geometry>

    <mesh

      filename="package://swurdf/meshes/link_1.STL" />

  </geometry>

  <material

    name="">

    <color

      rgba="0 1 0 1" />

  </material>

</visual>

<collision>

  <origin

    xyz ...