Industrial Arm Grasping
Scenario
Experiments
-Control
-Primitive/Tessellation
-Inertial Modification
For the industrial arm scenario, we acquired a model of the UR10 robotic arm from the ROS Industrial repository and converted it to GAZEBO’s SDF format. We combined this with a model that we composed of the Schunk MPG-80 hand, using CAD files from the manufacturer (and its technical schematics). We mated the Schunk hand to the UR10 arm to produce a 6-DOF arm with parallel gripper. The inertial properties for the UR10 arm came from the UR10’s URDF (and are presumably accurate). The inertial properties for the Schunk hand were set by approximating the bounding volume of the palm assembly and the individual fingers with boxes and apportioning the mass of the palm to be 80% of the total mass (described in the hand schematics); each of the two fingers were assigned the remaining 20% of the total mass. The box approximations were used for collision geometries in the geometric primitive experiments and the CAD meshes were used for collision geometries in the tessellated mesh experiments. The gripper prismatic joints were constrained by joint limits derived from the stroke per finger (defined in the schematics). Each gripper is actuated toward closure with 100N of force, which should be sufficient to maintain force closure on even dense objects.
The object to be grasped was modeled as a simple cube with equal dimensions of 100mm. This provided us with a primitive/primitive representation, which we hypothesized would yield more robust grasping than using primitive/mesh or mesh/mesh-based experiments. For the geometric primitive experiments a collision box was used; for the tessellated mesh experiments, a mesh was generated in BLENDER using the same dimensions as the cube. The mass of the object to be grasped was set to 1 kg, and its inertial tensor was derived from a box with given dimensions and mass.
The arm controller was designed to move the arm through randomized sinusoidal trajectories for all joints using PD-control. The amplitude of each sinusoid was tuned to be as large as possible without the arm colliding with either itself or the ground plane. The prismatic joints controlling the grippers applied 100N of constant force.
Note: Videos of the results are available on the Videos page.
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 2.249 | 2.25283 |
| ODE (tuned) | 14.382 | 30.0147 |
| DART (default) | 33.35 | 33.5573 |
| Bullet (default) | 8.505 | 8.53675 |
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 1.852 | 1.85148 |
| ODE (tuned) | 14.499 | 27.7441 |
| DART (default) | 43.673 | 44.0366 |
| Bullet (default) | 13.374 | 13.4436 |
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| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 1.656 | 1.65904 |
| ODE (tuned) | 1.656 | 2.59754 |
| DART (default) | NA | NA |
| Bullet (default) | NA | NA |
Note: NA is recorded for both DART and BULLET because they immediately crash and no data is captured from the simulation.
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 1.656 | 1.65687 |
| ODE (tuned) | 1.656 | 2.64722 |
| DART (default) | NA | NA |
| Bullet (default) | NA | NA |
Note: NA is recorded for both DART and BULLET because they immediately crash and no data is captured from the simulation.
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 19.839 | 19.9434 |
| ODE (tuned) | 4.148 | 9.20683 |
| DART (default) | 100 | 118.716 |
| Bullet (default) | 0.718 | 13.943 |
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 11.249 | 11.2861 |
| ODE (tuned) | 4.119 | 9.1931 |
| DART (default) | 99.321 | 116.578 |
| Bullet (default) | 0.618 | 12.0107 |
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 1.656 | 1.66013 |
| ODE (tuned) | 1.656 | 2.67976 |
| DART (default) | NA | NA |
| Bullet (default) | NA | NA |
Note: NA is recorded for both DART and BULLET because they immediately crash and no data is captured from the simulation.
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 1.656 | 1.657 |
| ODE (tuned) | 1.656 | 2.69536 |
| DART (default) | NA | NA |
| Bullet (default) | NA | NA |
Note: NA is recorded for both DART and BULLET because they immediately crash and no data is captured from the simulation.
==========================
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 11.419 | 11.4851 |
| ODE (tuned) | 100 | 187.913 |
| DART (default) | 100 | 100.596 |
| Bullet (default) | 0.702 | 13.7842 |
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 14.873 | 14.9174 |
| ODE (tuned) | 100 | 182.079 |
| DART (default) | 63.572 | 63.8316 |
| Bullet (default) | 0.715 | 13.7165 |
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 1.533 | 1.54477 |
| ODE (tuned) | 1.681 | 2.68096 |
| DART (default) | 20.946 | 21.1052 |
| Bullet (default) | 1.023 | 19.6004 |
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 1.533 | 1.53322 |
| ODE (tuned) | 1.728 | 2.77965 |
| DART (default) | 31.152 | 31.2837 |
| Bullet (default) | 0.155 | 2.97533 |
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 1.537 | 1.53907 |
| ODE (tuned) | 1.688 | 2.80886 |
| DART (default) | 1.489 | 1.49198 |
| Bullet (default) | NA | NA |
Note: NA is recorded for BULLET because it immediately crashes and no data is captured from the simulation.
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 1.537 | 1.53924 |
| ODE (tuned) | 1.783 | 2.92318 |
| DART (default) | 1.486 | 1.49032 |
| Bullet (default) | 3.117 | 3.12313 |
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 0.002 | NA |
| ODE (tuned) | 0.002 | NA |
| DART (default) | 0.002 | NA |
| Bullet (default) | NA | NA |
Note: NA is recorded for all dynamics engines because they immediately crash and no data is captured from the simulation.
| Dynamics | Total Sim Time (s) | Total Real Time (s) |
|---|---|---|
| ODE (default) | 0.002 | NA |
| ODE (tuned) | 0.002 | NA |
| DART (default) | 0.002 | NA |
| Bullet (default) | 0.161 | 3.09429 |
Note: NA is recorded for all dynamics engines except BULLET because they immediately crash and no data is captured from the simulation. Even though BULLET doesn't immediately crash, no data is generated.
Note: For all engines with the 1/10 inertia formulation, the dynamics engines crashed and no data was generated.
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