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No kinematics solver instantiated for group with 2 arms I have 2 plannings groups and want to move them at the same time

I decided to give Trac IK a shot after urkinematics solver was too hard to implement on 2 ur10 robots.

It's "fine" I guess, aside from not being able to find IK once in a while but it is what it is.

My problem is I cannot get a cartesian path be it over the MotionPlanner Plugin on rviz or in python code. It just fails and gives this back

Computed Cartesian path with 1 points (followed 0.000000% of requested trajectory)

Also I would love to know what kind of parameters you guys set for the Trac IK solver. Would appreciate it if you have some tips for the UR10 robot too :)

EDIT:

More informations on my setup as wished!

So, I have 2 UR10 robots 1m distance in between them but I assume this doesn't really matter since KDL does solve cartesian path with no problems on both robots. Anyway, after planning with my python file a non cartesian path one of the UR robots has to rotate around a certain position. Meaning, I am just adding a certain amount of orientation on the z axis. Does as it should on KDL (aside from complete twists and jumps at full speed, forcing the robot to a certain place when not reachable at first).

Trac IK seems to have problems with the start state of the robots. After moving the robots to a certain point, replanning with cartesian paths fails even with the motionplanning plugin. If I set a new position with the interactive marker, plan and execute that (meaning I "refresh" the start position of the arms) I can plan with cartesian again but over the plugin.

After executing my code, planning with the plugin gives this error code:

Invalid Trajectory: start point deviates from current robot state more than 0.01 joint 'right_elbow_joint': expected: 2.21799, current: 1.7153

This is the section in which cartesian is planned:

        for cartesians in range(0, 2):

            rospy.sleep(1)

            self.move_group.set_start_state(self.move_group.get_current_state())
            self.move_group_left.set_start_state(self.move_group.get_current_state()) #planning for the right arm for now

            rospy.sleep(0.3)

            wpose = self.move_group.get_current_pose().pose
            wpose.orientation.z += self.pose_goal.pose.orientation.z/4

            self.waypoints.append(copy.deepcopy(wpose))

            cart_found = False

            while cart_found == False:
                (plan_cart, fraction) = self.move_group.compute_cartesian_path(
                                                self.waypoints,   # waypoints to follow
                                                0.01,        # eef_step
                                                0.0)         # jump_threshold

                quest = raw_input("Ausfuehren?(ja/nein): ")

                if(quest == "ja"):

                    self.move_group.execute(plan_cart, wait=True)

                    #self.sub_img =  rospy.wait_for_message('/camera/color/image_raw',Image, timeout=None)

                    #savedimage = self.saveImg(self.sub_img)
                    cart_found = True

        rospy.loginfo('Ausgefuehrt!')

my kinematics yaml:

arm_right:
  kinematics_solver: trac_ik_kinematics_plugin/TRAC_IKKinematicsPlugin
  kinematics_solver_search_resolution: 0.005
  kinematics_solver_timeout: 0.005
  solve_type: Distance
arm_left:
  kinematics_solver: trac_ik_kinematics_plugin/TRAC_IKKinematicsPlugin
  kinematics_solver_search_resolution: 0.005
  kinematics_solver_timeout: 0.005
  solve_type: Distance

While writing the python script I realised something very dumb: I had another frame set as end effector so the robots wo

While writing the python script I realised something very dumb of me: I had another frame set as end effector so the rob

I worded it extremely bad I guess. Sorry. I was working with quaternions for normal planning but couldn't use it for car

I worded it extremely bad I guess. Sorry. I was working with quaternions for normal planning but couldn't use it for car

I was actually working directly with quaternions and euler angles and this was just a random test. Extremely random. I w

Good point, will edit it later! EDIT: I edited my post, also as a side comment: I removed the set_start_state functions

Trac IK cannot computeCartesian path at all I decided to give Trac IK a shot after urkinematics solver was too hard to i

Good point, will edit it later!

Did that already, still not working.Trac IK cannot perform the slightest amount of motion with cartesian. I have absolut

Trac IK cannot computeCartesian path at all I decided to give Trac IK a shot after urkinematics solver was too hard to i

Cannot change the prefix of URkinematics to a postfix ROS Melodic Ubuntu 18.04 Admittedly, I have 0 clue of c++, so I h

Cannot change the prefix of URkinematics to a postfix ROS Melodic Ubuntu 18.04 Admittedly, I have 0 clue of c++, so I h

Okay sorry for double commenting/spaming but would you put that extra frame at the tip in the URDF or is it possible to

Okay sorry for double commenting/spaming but would you put that extra frame at the tip in the URDF or is it possible to

So I wasted a lot of time on this and can't seem to solve it:

I have a UR10 robot which I want to move towards/approach an object. I use TF/TF2 to get the position/orientation of said object and give it to moveit with /compute_ik and joint spaces. Moving to that point given by TF isn't a problem. Problematic is though, I have no idea how to make the end effector LOOK at the object. Also I want the robot to approach the point rather than go into it (since its supposed to be an object in real life on a table). I don't know what kind of math to do here. Also, I am a complete beginner on ROS and didnt do math in a while. Sorry for the dumb question.

What I tried:

rotation = self.move_group.get_current_rpy()
            quat_ee = tf.transformations.quaternion_from_euler(rotation[0], rotation[1], rotation[2])
            quat_object = tf.transformations.quaternion_from_euler(self.rotation_object[0], self.rotation_object[1], self.rotation_object[2])

            self.new_quat = quaternion_multiply(quat_ee, quat_object)

then I pass the new_quat to the orientation of the robot:

          self.pose_goal.pose.orientation = geometry_msgs.msg.Quaternion(*self.new_quat)

On an honest note, I have absolutely 0 clue if that makes even sense.

I use Python on ROS Melodic.

I would love to jump ships to C++ but Uni is kinda tough rn. If anyone has some clue I would appreciate it a lot if you could help me in Python!

Problematic with that is, that the orientation is from before the robot moves to the object, which means the end orienta

Thanks for your answer! Knowing that I am on the right track is already a lot of help. Plus the code linked does help a

how to make end effector look at object? So I wasted a lot of time on this and can't seem to solve it: I have a UR10 ro

Weird MoveIt error when using /compute_ik this is the error I get. I have 2 planning groups arm_right and arm_left. arm_

Using rviz_visual_tools and moveit_visual_tools in python Following the MoveIt movegroup c++ interface, you can visualiz