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link position not in correct position

<?xml version="1.0"?>

<robot name="blackBird">


  <link name="body">

    <visual>
      <geometry>
        <mesh filename="package://urdf_tutorial/meshes/body.dae"/>
      </geometry>
      <material
        name="">
        <color
          rgba="0 1 0 1" />
      </material>
    </visual>

    <collision>
      <geometry>
        <mesh filename="package://urdf_tutorial/meshes/body.dae"/>
      </geometry>
    </collision>
    <inertial>
      <mass value="0.0001"/>
      <inertia ixx="0.03410357" ixy="0.00003043" ixz="0.000043960" iyy="0.003279236" iyz="0.0" izz="0.000259210"/>
    </inertial>

  </link>
  <link name="blade">
    <visual>
      <origin rpy="0 0 0" xyz="0 0 10"/>
      <geometry>
        <mesh filename="package://urdf_tutorial/meshes/blade.dae"/>
      </geometry>
      <material name="blue">
        <color rgba="0 0 0.8 1"/>
      </material>
    </visual>

    <collision>
      <geometry>
        <mesh filename="package://urdf_tutorial/meshes/blade.dae"/>
      </geometry>
    </collision>
    <inertial>
      <mass value="0.0001"/>
      <inertia ixx="0.000251114" ixy="0.000002954" ixz="0.000185428" iyy="0.003055804" iyz="0.0" izz="0.002817239"/>
    </inertial>

  </link>

  <joint name="joint1" type="continuous">
    <parent link="body"/>
    <child link="blade"/>
    <axis xyz="0 0 1"/>
    <origin xyz="0.105987 3.12205 12.4372"/>
  </joint>

</robot>

above is the urdf of model. here no matter how much i change the position of the link blade, it's position don't changes from one position. image description

what should i do? i have placed its position in blender correctly. i'm using gazebo 9. when i place its position as 0 0 0 its position comes correctely but the joint position is at 0 0 0. so the problem is when ever i change the position of the joint the position of the blade link also chagnes. in rviz the model with joint position 0 0 0: image description

Asked by dinesh on 2018-05-23 11:27:01 UTC

Comments

Three questions: 1. You're saying that if you change a visual origin value the blade is in the same place as before? 2. You ought to have the same origin for your collision element as for your visual element, right? 3. What's wrong with the joint position and the link origin both being at 0, 0, 0?

Asked by raequin on 2018-05-23 15:28:31 UTC

  1. yes. 2. yes. 3. its a continious joint so, it should be at correct place so that when blade rotates it looks correct.

Asked by dinesh on 2018-05-23 22:49:20 UTC

@dinesh: Where did you get the mesh files (e.g., blade.dae and body.dae) for this helicopter model? I'm trying to test your model but the "urdf_tutorial" package doesn't contain these files.

Asked by ubuntuslave on 2019-04-05 11:47:04 UTC

here: https://github.com/roboticsai/blackBird_Project/tree/master/blackBird_description/meshes

Asked by dinesh on 2019-04-06 10:41:13 UTC

Answers

ok after i exported the blade link to blender and than made its origin point and median point same at origin i.e xyz=000 it is going to correct position along with joint position. but i don't know why is the model looking transparent in rviz. image description

Asked by dinesh on 2018-05-23 23:42:21 UTC

Comments