[Bug]: Unable to Perform Static Pick and Place with Inverse Kinematics on Modified WidowXL Arm

[AltziTS007]

I am using a modified WidowXL arm, which I successfully configured in the MoveIt Setup Assistant. I can execute every pose I created without any issues. However, I am facing a problem when trying to perform a static pick and place operation using inverse kinematics.

The pose we are trying to achieve is a valid pose that can be executed through MoveIt without any problems. However, when attempting to reach the same pose using inverse kinematics, it fails. The motion planning either does not generate a valid trajectory or does not execute correctly.

I am using a modified version of the WidowXL arm, and I can provide URDF modifications or any other relevant configurations if needed. Since the pose works fine in MoveIt, are there any specific parameters or settings that might be affecting the IK solver?

System details:

OS: ubuntu 18.04.6
ROS Version: melodic

My code is this :

#!/usr/bin/env python2
# -*- coding: utf-8 -*-

import rospy
import moveit_commander
import geometry_msgs.msg
from moveit_commander.conversions import pose_to_list

def all_close(goal, actual, tolerance=0.01):
    if isinstance(goal, list):
        return all(abs(a - g) < tolerance for a, g in zip(actual, goal))
    return False

def compute_inverse_kinematics():
    rospy.init_node("inverse_kinematics_solver", anonymous=True)
    moveit_commander.roscpp_initialize([])
    
    robot = moveit_commander.RobotCommander()
    scene = moveit_commander.PlanningSceneInterface()
    group_name = "arm_manipulator"  # Adjust based on your SRDF MoveIt group
    move_group = moveit_commander.MoveGroupCommander(group_name)
    move_group.set_path_constraints(None)  # Remove constraints
    move_group.set_planning_time(10.0)  # Increase planning time
    move_group.set_num_planning_attempts(10)  # Allow multiple attempts
    move_group.set_max_velocity_scaling_factor(1.0)
    move_group.set_max_acceleration_scaling_factor(1.0)
    move_group.set_goal_tolerance(0.01)
    move_group.allow_replanning(True)
    
    print "Robot group set to:", move_group.get_name()
    
    target_pose = geometry_msgs.msg.Pose()
    target_pose.position.x = 0.1  # sleep position
    target_pose.position.y = 0.0
    target_pose.position.z = 0.34
    target_pose.orientation.x = 0.0
    target_pose.orientation.y = -0.366
    target_pose.orientation.z = 0.0
    target_pose.orientation.w = 0.93
    
    move_group.set_pose_target(target_pose)
    move_group.set_start_state_to_current_state()  # Ensure valid start state
    
    plan = move_group.plan()
    if plan and plan.joint_trajectory.points:  # Check if the trajectory contains points
        move_group.execute(plan, wait=True)  # Explicit execution
        print " Plan executed successfully!"
    else:
        print " MoveIt failed to generate a valid plan"
    
    move_group.stop()
    move_group.clear_pose_targets()
    
    joint_values = move_group.get_current_joint_values()
    print "Computed Joint Values:", joint_values
    print "Planning Frame:", move_group.get_planning_frame()
    print "End Effector Link:", move_group.get_end_effector_link()
    print "Current End-Effector Pose:", move_group.get_current_pose().pose
    print "Available Planners:", move_group.get_interface_description()
    print "Robot Model Loaded:", move_group.get_name()
    print "Joint Names:", move_group.get_active_joints()
    
    moveit_commander.roscpp_shutdown()
    return joint_values

if __name__ == "__main__":
    try:
        joint_angles = compute_inverse_kinematics()
        print "Resulting Joint Angles:", joint_angles
    except rospy.ROSInterruptException:
        pass
    except KeyboardInterrupt:
        pass

---

The warning i get is this : [ WARN] [1741292075.512546270]: Fail: ABORTED: Catastrophic failure
and the error i get from moveit is this : [ERROR] [1741291121.714569183]: Unable to construct goal representation

Any guidance or suggestions would be greatly appreciated. Thanks in advance!

Robot Model

modified widowxl arm

Operating System

Ubuntu 18.04

ROS Distro

ROS 1 Melodic

Steps To Reproduce

No response

Relevant log output

Additional Info

No response