Let's get you a robot!

Follow live at https://slides.com/d/YBo9i4k/live

(or later at https://slides.com/russtedrake/fall22-lec02)

Robotic Manipulation

Fall 2022, Lecture 2

Today

  • Robot arms.
    • The hardware matters.
    • Why did we pick iiwa?
  • Physics \( \subset \) Simulation
  • Robot hands.  Why did we pick wsg?

Click here

https://www.infineon.com/cms/en/discoveries/robotics-systems-safety-security/

https://spectrum.ieee.org/robotics/industrial-robots/rethink-robotics-baxter-robot-factory-worker

Universal Robots

Rethink

Kuka

Kinova

ABB

Franka

http://robotpark.com/academy/gear-motors-gearboxes-51055/

 A. Albu-Schäffer, S. Haddadin, C. Ott, A. Stemmer, T. Wimböck, and G. Hirzinger, "The DLR lightweight robot: design and control concepts for robots in human environments," Industrial Robot: An International Journal, vol. 34, pp. 376-385, 2007.

Atlas (v1) by Boston Dynamics

from pydrake.all import MultibodyPlant, FindResourceOrThrow, Parser

plant = MultibodyPlant(time_step=1e-4)
Parser(plant).AddModelFromFile(".../iiwa14_no_collision.sdf")
plant.WeldFrames(plant.world_frame(), plant.GetFrameByName("iiwa_link_0"))
plant.Finalize()

Drake's Physics Engine: MultibodyPlant

<?xml version="1.0"?>
<sdf version="1.7">
  <model name="iiwa14">
    <link name="iiwa_link_0">
      <inertial>
        <pose>-0.1 0 0.07 0 0 0</pose>
        <mass>5</mass>
        <inertia>
          <ixx>0.05</ixx>
          <ixy>0</ixy>
          <ixz>0</ixz>
          <iyy>0.06</iyy>
          <iyz>0</iyz>
          <izz>0.03</izz>
        </inertia>
      </inertial>
      <visual name="iiwa_link_0_fixed_joint_lump__iiwa_link_0_visual">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_0.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.4 0.4 0.4 1.0</diffuse>
        </material>
      </visual>
      <gravity>1</gravity>
      <velocity_decay/>
      <self_collide>0</self_collide>
    </link>
    <link name="iiwa_link_1">
      <pose relative_to="iiwa_joint_1"/>
      <inertial>
        <pose>0 -0.03 0.12 0 0 0</pose>
        <mass>5.76</mass>
        <inertia>
          <ixx>0.033</ixx>
          <ixy>0</ixy>
          <ixz>0</ixz>
          <iyy>0.0333</iyy>
          <iyz>0</iyz>
          <izz>0.0123</izz>
        </inertia>
      </inertial>
      <visual name="iiwa_link_1_visual">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_1.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.4 0.4 0.4 1.0</diffuse>
        </material>
      </visual>
      <gravity>1</gravity>
      <velocity_decay/>
      <self_collide>0</self_collide>
    </link>
    <joint name="iiwa_joint_1" type="revolute">
      <pose relative_to="iiwa_link_0">0 0 0.1575 0 0 0</pose>
      <child>iiwa_link_1</child>
      <parent>iiwa_link_0</parent>
      <axis>
        <xyz>0 0 1</xyz>
        <limit>
          <lower>-2.96706</lower>
          <upper>2.96706</upper>
          <effort>300</effort>
          <velocity>10</velocity>
        </limit>
        <dynamics>
          <damping>0.0</damping>
          <friction>0</friction>
          <spring_reference>0</spring_reference>
          <spring_stiffness>0</spring_stiffness>
        </dynamics>
      </axis>
    </joint>
    <link name="iiwa_link_2">
      <pose relative_to="iiwa_joint_2"/>
      <inertial>
        <pose>0.0003 0.059 0.042 0 0 0</pose>
        <mass>6.35</mass>
        <inertia>
          <ixx>0.0305</ixx>
          <ixy>0</ixy>
          <ixz>0</ixz>
          <iyy>0.0304</iyy>
          <iyz>0</iyz>
          <izz>0.011</izz>
        </inertia>
      </inertial>
      <visual name="iiwa_link_2_visual_grey">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_2_grey.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.4 0.4 0.4 1.0</diffuse>
        </material>
      </visual>
      <visual name="iiwa_link_2_visual_orange">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_2_orange.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>1.0 0.423529411765 0.0392156862745 1.0</diffuse>
        </material>
      </visual>
      <gravity>1</gravity>
      <velocity_decay/>
      <self_collide>0</self_collide>
    </link>
    <joint name="iiwa_joint_2" type="revolute">
      <pose relative_to="iiwa_link_1">
        0 0 0.2025 1.570796326794897 0 3.141592653589793
      </pose>
      <child>iiwa_link_2</child>
      <parent>iiwa_link_1</parent>
      <axis>
        <xyz>0 0 1</xyz>
        <limit>
          <lower>-2.0944</lower>
          <upper>2.0944</upper>
          <effort>300</effort>
          <velocity>10</velocity>
        </limit>
        <dynamics>
          <damping>0.0</damping>
          <friction>0</friction>
          <spring_reference>0</spring_reference>
          <spring_stiffness>0</spring_stiffness>
        </dynamics>
      </axis>
    </joint>
    <link name="iiwa_link_3">
      <pose relative_to="iiwa_joint_3"/>
      <inertial>
        <pose>0 0.03 0.13 0 0 0</pose>
        <mass>3.5</mass>
        <inertia>
          <ixx>0.025</ixx>
          <ixy>0</ixy>
          <ixz>0</ixz>
          <iyy>0.0238</iyy>
          <iyz>0</iyz>
          <izz>0.0076</izz>
        </inertia>
      </inertial>
      <visual name="iiwa_link_3_visual">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_3.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.4 0.4 0.4 1.0</diffuse>
        </material>
      </visual>
      <visual name="iiwa_link_3_visual_band">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/band.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.6 0.6 0.6 1.0</diffuse>
        </material>
      </visual>
      <visual name="iiwa_link_3_visual_kuka">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/kuka.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0 0 0 1</diffuse>
        </material>
      </visual>
      <gravity>1</gravity>
      <velocity_decay/>
      <self_collide>0</self_collide>
    </link>
    <joint name="iiwa_joint_3" type="revolute">
      <pose relative_to="iiwa_link_2">0 0.2045 0 1.570796326794897 0 3.141592653589793</pose>
      <child>iiwa_link_3</child>
      <parent>iiwa_link_2</parent>
      <axis>
        <xyz>0 0 1</xyz>
        <limit>
          <lower>-2.96706</lower>
          <upper>2.96706</upper>
          <effort>300</effort>
          <velocity>10</velocity>
        </limit>
        <dynamics>
          <damping>0.0</damping>
          <friction>0</friction>
          <spring_reference>0</spring_reference>
          <spring_stiffness>0</spring_stiffness>
        </dynamics>
      </axis>
    </joint>
    <link name="iiwa_link_4">
      <pose relative_to="iiwa_joint_4"/>
      <inertial>
        <pose>0 0.067 0.034 0 0 0</pose>
        <mass>3.5</mass>
        <inertia>
          <ixx>0.017</ixx>
          <ixy>0</ixy>
          <ixz>0</ixz>
          <iyy>0.0164</iyy>
          <iyz>0</iyz>
          <izz>0.006</izz>
        </inertia>
      </inertial>
      <visual name="iiwa_link_4_visual_grey">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_4_grey.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.4 0.4 0.4 1.0</diffuse>
        </material>
      </visual>
      <visual name="iiwa_link_4_visual_orange">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_4_orange.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>1.0 0.423529411765 0.0392156862745 1.0</diffuse>
        </material>
      </visual>
      <gravity>1</gravity>
      <velocity_decay/>
      <self_collide>0</self_collide>
    </link>
    <joint name="iiwa_joint_4" type="revolute">
      <pose relative_to="iiwa_link_3">0 0 0.2155 1.570796326794897 0 0</pose>
      <child>iiwa_link_4</child>
      <parent>iiwa_link_3</parent>
      <axis>
        <xyz>0 0 1</xyz>
        <limit>
          <lower>-2.0944</lower>
          <upper>2.0944</upper>
          <effort>300</effort>
          <velocity>10</velocity>
        </limit>
        <dynamics>
          <damping>0.0</damping>
          <friction>0</friction>
          <spring_reference>0</spring_reference>
          <spring_stiffness>0</spring_stiffness>
        </dynamics>
      </axis>
    </joint>
    <link name="iiwa_link_5">
      <pose relative_to="iiwa_joint_5"/>
      <inertial>
        <pose>0.0001 0.021 0.076 0 0 0</pose>
        <mass>3.5</mass>
        <inertia>
          <ixx>0.01</ixx>
          <ixy>0</ixy>
          <ixz>0</ixz>
          <iyy>0.0087</iyy>
          <iyz>0</iyz>
          <izz>0.00449</izz>
        </inertia>
      </inertial>
      <visual name="iiwa_link_5_visual">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_5.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.4 0.4 0.4 1.0</diffuse>
        </material>
      </visual>
      <visual name="iiwa_link_5_visual_band">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/band.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.6 0.6 0.6 1.0</diffuse>
        </material>
      </visual>
      <visual name="iiwa_link_5_visual_kuka">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/kuka.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0 0 0 1</diffuse>
        </material>
      </visual>
      <gravity>1</gravity>
      <velocity_decay/>
      <self_collide>0</self_collide>
    </link>
    <joint name="iiwa_joint_5" type="revolute">
      <pose relative_to="iiwa_link_4">0 0.1845 0 -1.570796326794897 3.141592653589793 0</pose>
      <child>iiwa_link_5</child>
      <parent>iiwa_link_4</parent>
      <axis>
        <xyz>0 0 1</xyz>
        <limit>
          <lower>-2.96706</lower>
          <upper>2.96706</upper>
          <effort>300</effort>
          <velocity>10</velocity>
        </limit>
        <dynamics>
          <damping>0.0</damping>
          <friction>0</friction>
          <spring_reference>0</spring_reference>
          <spring_stiffness>0</spring_stiffness>
        </dynamics>
      </axis>
    </joint>
    <link name="iiwa_link_6">
      <pose relative_to="iiwa_joint_6"/>
      <inertial>
        <pose>0 0.0006 0.0004 0 0 0</pose>
        <mass>1.8</mass>
        <inertia>
          <ixx>0.0049</ixx>
          <ixy>0</ixy>
          <ixz>0</ixz>
          <iyy>0.0047</iyy>
          <iyz>0</iyz>
          <izz>0.0036</izz>
        </inertia>
      </inertial>
      <visual name="iiwa_link_6_visual_grey">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_6_grey.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.4 0.4 0.4 1.0</diffuse>
        </material>
      </visual>
      <visual name="iiwa_link_6_visual_orange">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_6_orange.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>1.0 0.423529411765 0.0392156862745 1.0</diffuse>
        </material>
      </visual>
      <gravity>1</gravity>
      <velocity_decay/>
      <self_collide>0</self_collide>
    </link>
    <joint name="iiwa_joint_6" type="revolute">
      <pose relative_to="iiwa_link_5">0 0 0.2155 1.570796326794897 0 0</pose>
      <child>iiwa_link_6</child>
      <parent>iiwa_link_5</parent>
      <axis>
        <xyz>0 0 1</xyz>
        <limit>
          <lower>-2.0944</lower>
          <upper>2.0944</upper>
          <effort>300</effort>
          <velocity>10</velocity>
        </limit>
        <dynamics>
          <damping>0.0</damping>
          <friction>0</friction>
          <spring_reference>0</spring_reference>
          <spring_stiffness>0</spring_stiffness>
        </dynamics>
      </axis>
    </joint>
    <link name="iiwa_link_7">
      <pose relative_to="iiwa_joint_7"/>
      <inertial>
        <pose>0 0 0.02 0 0 0</pose>
        <mass>1.2</mass>
        <inertia>
          <ixx>0.001</ixx>
          <ixy>0</ixy>
          <ixz>0</ixz>
          <iyy>0.001</iyy>
          <iyz>0</iyz>
          <izz>0.001</izz>
        </inertia>
      </inertial>
      <visual name="iiwa_link_7_visual">
        <geometry>
          <mesh>
            <scale>1 1 1</scale>
            <uri>../meshes/visual/link_7.obj</uri>
          </mesh>
        </geometry>
        <material>
          <diffuse>0.4 0.4 0.4 1.0</diffuse>
        </material>
      </visual>
      <gravity>1</gravity>
      <velocity_decay/>
      <self_collide>0</self_collide>
    </link>
    <joint name="iiwa_joint_7" type="revolute">
      <pose relative_to="iiwa_link_6">
        0 0.081 0 -1.570796326794897 3.141592653589793 0
      </pose>
      <child>iiwa_link_7</child>
      <parent>iiwa_link_6</parent>
      <axis>
        <xyz>0 0 1</xyz>
        <limit>
          <lower>-3.05433</lower>
          <upper>3.05433</upper>
          <effort>300</effort>
          <velocity>10</velocity>
        </limit>
        <dynamics>
          <damping>0.0</damping>
          <friction>0</friction>
          <spring_reference>0</spring_reference>
          <spring_stiffness>0</spring_stiffness>
        </dynamics>
      </axis>
    </joint>
    <static>0</static>
    <plugin name="gazebo_ros_controller" filename="libgazebo_ros_control.so">
      <robotNamespace>/iiwa</robotNamespace>
    </plugin>
  </model>
</sdf>

Robot Description Files

Drake's Model Directives

model_directives = """
directives:
- add_directives:
    file: package://manipulation/clutter.dmd.yaml
- add_model:
    name: foam_brick
    file: package://drake/examples/manipulation_station/models/061_foam_brick.sdf
    default_free_body_pose:
        base_link:
            translation: [0, -0.6, 0.2]
"""

builder = DiagramBuilder()
station = builder.AddSystem(MakeManipulationStation(model_directives, time_step=0.005))
...
diagram = builder.Build()

Today

  • Robot arms.
    • The hardware matters.
    • Why did we pick iiwa?
  • Physics \( \subset \) Simulation
  • Robot hands.  Why did we pick wsg?

http://personalrobotics.stanford.edu/

Schunk WSG 50

Force-controlled planar gripper

Sandia Hand

iHY (i-Robot, Harvard, Yale)

Robotiq 3-fingered gripper

Mobile Manipulators

Lecture 2: Let's get you a robot!

By russtedrake

Lecture 2: Let's get you a robot!

MIT Robotic Manipulation Fall 2020 http://manipulation.csail.mit.edu

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