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Real UR5 Error RRTConnect: Unable to sample any valid states for goal tree

asked 2019-11-25 06:55:06 -0600

shu gravatar image

I'm using a UR5 which and am trying to move the robot forward 0.1m in the y direction. Here are my start up commands:

roslaunch ur_robot_driver ur5_bringup.launch robot_ip:=169.254.198.35 kinematics_config:="${HOME}/my_robot_calibration.yaml"
roslaunch ur5_moveit_config ur5_moveit_planning_execution.launch sim:=true
roslaunch ur5_moveit_config moveit_rviz.launch config:=true

Some information on the current starting position of the UR5 (Don't have the points to upload pictures unfortunately):

joint positions: [-1.5844348112689417, -0.9981825987445276, -1.9562018553363245, -1.8684194723712366, 1.4567383527755737, 2.39935302734375]

Coordinates of End Effector: (0.12241, 0.23884, 0.4266)

Orientation of End Effector: [0.265, 0.5945, -0.307, 0.694]

My controllers.yaml file inside ur5_moveit_config/config file looks like this:

controller_list:
 - name: /scaled_pos_traj_controller
   action_ns: follow_joint_trajectory
   type: FollowJointTrajectory
   default: true
   joints:
      - shoulder_pan_joint
      - shoulder_lift_joint
      - elbow_joint
      - wrist_1_joint
  - wrist_2_joint
  - wrist_3_joint

My kinematics.yaml file also in ur5_moveit_config/config looks like this:

manipulator:
  kinematics_solver: trac_ik_kinematics_plugin/TRAC_IKKinematicsPlugin
  kinematics_solver_search_resolution: 0.005
  kinematics_solver_timeout: 0.01
  kinematics_solver_attempts: 3

Here is the console output of running roslaunch ur_robot_driver ur5_bringup.launch robot_ip:=169.254.198.35 kinematics_config:="${HOME}/my_robot_calibration.yaml"

... logging to /home/shu/.ros/log/e301052a-0f7d-11ea-9d0c-3c918077fd81/roslaunch-sewts-ideapad-002-26797.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://sewts-ideapad-002:39421/

SUMMARY
========

PARAMETERS
 * /controller_stopper/consistent_controllers: ['joint_state_con...
 * /force_torque_sensor_controller/publish_rate: 125
 * /force_torque_sensor_controller/type: force_torque_sens...
 * /hardware_control_loop/loop_hz: 125
 * /hardware_interface/joints: ['shoulder_pan_jo...
 * /joint_state_controller/publish_rate: 125
 * /joint_state_controller/type: joint_state_contr...
 * /pos_traj_controller/action_monitor_rate: 10
 * /pos_traj_controller/constraints/elbow_joint/goal: 0.1
 * /pos_traj_controller/constraints/elbow_joint/trajectory: 0.2
 * /pos_traj_controller/constraints/goal_time: 0.6
 * /pos_traj_controller/constraints/shoulder_lift_joint/goal: 0.1
 * /pos_traj_controller/constraints/shoulder_lift_joint/trajectory: 0.2
 * /pos_traj_controller/constraints/shoulder_pan_joint/goal: 0.1
 * /pos_traj_controller/constraints/shoulder_pan_joint/trajectory: 0.2
 * /pos_traj_controller/constraints/stopped_velocity_tolerance: 0.05
 * /pos_traj_controller/constraints/wrist_1_joint/goal: 0.1
 * /pos_traj_controller/constraints/wrist_1_joint/trajectory: 0.2
 * /pos_traj_controller/constraints/wrist_2_joint/goal: 0.1
 * /pos_traj_controller/constraints/wrist_2_joint/trajectory: 0.2
 * /pos_traj_controller/constraints/wrist_3_joint/goal: 0.1
 * /pos_traj_controller/constraints/wrist_3_joint/trajectory: 0.2
 * /pos_traj_controller/joints: ['shoulder_pan_jo...
 * /pos_traj_controller/state_publish_rate: 125
 * /pos_traj_controller/stop_trajectory_duration: 0.5
 * /pos_traj_controller/type: position_controll...
 * /robot_description: <?xml version="1....
 * /rosdistro: kinetic
 * /rosversion: 1.12.14
 * /scaled_pos_traj_controller/action_monitor_rate: 10
 * /scaled_pos_traj_controller/constraints/elbow_joint/goal: 0.1
 * /scaled_pos_traj_controller/constraints/elbow_joint/trajectory: 0.2
 * /scaled_pos_traj_controller/constraints/goal_time: 0.6
 * /scaled_pos_traj_controller/constraints/shoulder_lift_joint/goal: 0.1
 * /scaled_pos_traj_controller/constraints/shoulder_lift_joint/trajectory: 0.2
 * /scaled_pos_traj_controller/constraints/shoulder_pan_joint/goal: 0.1
 * /scaled_pos_traj_controller/constraints/shoulder_pan_joint/trajectory: 0.2
 * /scaled_pos_traj_controller/constraints/stopped_velocity_tolerance: 0.05
 * /scaled_pos_traj_controller/constraints/wrist_1_joint/goal: 0.1
 * /scaled_pos_traj_controller/constraints/wrist_1_joint/trajectory: 0.2
 * /scaled_pos_traj_controller/constraints/wrist_2_joint/goal: 0.1
 * /scaled_pos_traj_controller/constraints/wrist_2_joint/trajectory: 0.2
 * /scaled_pos_traj_controller/constraints/wrist_3_joint/goal: 0.1
 * /scaled_pos_traj_controller/constraints/wrist_3_joint/trajectory: 0.2
 * /scaled_pos_traj_controller/joints: ['shoulder_pan_jo...
 * /scaled_pos_traj_controller/state_publish_rate: 125
 * /scaled_pos_traj_controller/stop_trajectory_duration: 0.5
 * /scaled_pos_traj_controller/type: position_controll...
 * /speed_scaling_state_controller/publish_rate: 125
 * /speed_scaling_state_controller/type: ur_controllers/Sp...
 * /ur_hardware_interface/headless_mode: False
 * /ur_hardware_interface/input_recipe_file: /home/shu/catkin_...
 * /ur_hardware_interface/kinematics/forearm/pitch: 0.000670340723934
 * /ur_hardware_interface/kinematics/forearm/roll: 0.000150389826896
 * /ur_hardware_interface/kinematics/forearm/x: -0.425316567681
 * /ur_hardware_interface/kinematics/forearm/y: 0
 * /ur_hardware_interface/kinematics/forearm/yaw: -0.000129296667033
 * /ur_hardware_interface/kinematics/forearm/z: 0
 * /ur_hardware_interface/kinematics/hash: calib_72470218391...
 * /ur_hardware_interface/kinematics/shoulder ...
(more)
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answered 2019-11-26 08:29:25 -0600

AndyZe gravatar image

Maybe the robot is starting beyond a ROS joint limit. The wrist on the UR5 can rotate infinitely, which confuses ROS if it is beyond [-360,360] (or [-180,180] if you're using the joint-limited version).

It could be that it thinks the robot is in collision, too, but I think there would have been some more errors printed if that were the case.

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Comments

Unfortunately I don't think this is the case as I've tried giving the robot goals that have joints within -180 and 180. I've set a joint goal of [-1.8963, -0.5800, -2.2339, -1.8976, 1.5629, 2.0322] that always works, but the planner often fails for finding solutions for pose goals after reaching this joint goal. I have enjoyed a bit more success adding goals between the final goal and the starting position, but if the planner fails to find the solution for one it will never reach its end position.

shu gravatar imageshu ( 2019-11-28 04:14:04 -0600 )edit

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Asked: 2019-11-25 06:55:06 -0600

Seen: 65 times

Last updated: Nov 26 '19