Skip to content

Commit b531c14

Browse files
zhigenzhaozhigenzhao
committed
updated readme and a1x joint damping
1 parent 19a6e3d commit b531c14

File tree

3 files changed

+119
-1
lines changed

3 files changed

+119
-1
lines changed

‎README.md

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -34,6 +34,7 @@ This project provides a framework for controlling robots in robot hardware and M
3434
2. Then, install this package using `pip install -e .` in your activated Conda environment or system Python. -->
3535

3636
## Usage
37+
Use the following instructions to run example scripts. For a more detailed description, please refer to [`teleop_details.md`](teleop_details.md).
3738

3839
### Running the MuJoCo Simulation Demo
3940

‎assets/galaxea/A1X/dual_a1x.xml

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -12,7 +12,7 @@
1212
<geom material="visualgeom" condim="1" contype="0" conaffinity="0" />
1313
</default>
1414
<default class="position_arm">
15-
<position kp="5000" kv="50" />
15+
<position kp="5000" kv="100" />
1616
</default>
1717
<default class="position_gripper">
1818
<position kp="1000" kv="10" />

‎teleop_details.md

Lines changed: 117 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,117 @@
1+
# Detailed descriptions on the python teleoperation examples
2+
3+
## XR client
4+
- https://github.com/XR-Robotics/XRoboToolkit-Teleop-Sample-Python/blob/main/xrobotoolkit_teleop/utils/xr_client.py
5+
- connects to XR device using the python binding of [xrobotoolkit-sdk](https://github.com/XR-Robotics/XRoboToolkit-PC-Service-Pybind)
6+
7+
## Placo
8+
- [PlaCo](https://placo.readthedocs.io/en/latest/) is an implementation for whole-body inverse kinematics and dynamics based on Quadratic Programming solver.
9+
- Tasks: following are the main placo tasks used in this repo
10+
- Frame Task
11+
- Constraints position and orientation of a frame, used to define end-effector tracking goals for IK
12+
- Manipulability Task
13+
- Makes robot motion stable when commanded position is close to singularity or outside of workspace
14+
- Based on this paper: https://arxiv.org/abs/2002.11901
15+
- Kinetic Energy Regularization
16+
- Minimizes the kinetic energy of the system
17+
- Joint Task
18+
- Regularizes the joint state to be close to the default state
19+
20+
## Mujoco simulation
21+
- Robot definition files: both `.xml` and `.urdf` files are required and they should be consistent with each other (same link names and joint names). The `.xml` file is for mujoco simulation, and the `.urdf` is for placo. Optionally, there should be 1 additional free floating body per end effector defined in the `.xml` file for visualization of commanded teleop targets in mujoco.
22+
- Teleoperation task is defined by a config dict
23+
- link_name: the name of end effector link as defined in mujoco .xml & .urdf files
24+
- pose_source: name of the source of pose to be used by Pico client
25+
- control_trigger: the key to define whether an arm control is active
26+
- vis_target: name of the body for teleop target visualization
27+
```python
28+
config = {
29+
"right_hand": {
30+
"link_name": "right_tool0",
31+
"pose_source": "right_controller",
32+
"control_trigger": "right_grip",
33+
"gripper_trigger": "right_trigger",
34+
"vis_target": "right_target", # optional, only used in mujoco
35+
},
36+
"left_hand": {
37+
"link_name": "left_tool0",
38+
"pose_source": "left_controller",
39+
"control_trigger": "left_grip",
40+
"gripper_trigger": "left_trigger",
41+
"vis_target": "left_target", # optional, only used in mujoco
42+
},
43+
}
44+
```
45+
46+
- Run mujoco demo for dual UR5e with the following script
47+
```bash
48+
python scripts/simulation/teleop_dual_ur5e_mujoco.py
49+
```
50+
51+
- Controlling parallel gripper in mujoco simulation
52+
- Users can add an optional gripper configuration in the end effector config dict
53+
- joint_name: the actuated mujoco joint within the gripper
54+
- gripper_trigger: name of the key mapped to this gripper from the controller
55+
- open_pos: the value of the actuated joint when fully opened
56+
- close_pos: the value of the actuated joint when fully closed
57+
```python
58+
config = {
59+
"right_hand": {
60+
# other configs,
61+
"gripper_config": {
62+
"joint_name": "right_gripper_finger_joint1",
63+
"gripper_trigger": "right_trigger",
64+
"open_pos": 0.05,
65+
"close_pos": 0.0,
66+
},
67+
},
68+
"left_hand": {
69+
# other configs,
70+
"gripper_config": {
71+
"joint_name": "left_gripper_finger_joint1",
72+
"gripper_trigger": "left_trigger",
73+
"open_pos": 0.05,
74+
"close_pos": 0.0,
75+
},
76+
},
77+
}
78+
```
79+
- Note that the parallel gripper might contain multiple joints in the `.xml` file, but only 1 of the joints should be actuated, the others should be controlled by additional equality constraints in the xml. The `.urdf` file supplied to Placo does not have to contain the gripper dof.
80+
```xml
81+
<equality>
82+
<joint name="right_gripper_constraint" joint1="right_gripper_finger_joint1" joint2="right_gripper_finger_joint2" polycoef="0 -1 0 0 0" />
83+
<joint name="left_gripper_constraint" joint1="left_gripper_finger_joint1" joint2="left_gripper_finger_joint2" polycoef="0 -1 0 0 0" />
84+
</equality>
85+
```
86+
- Example of mujoco teleoperation with gripper control using dual A1X arm
87+
```bash
88+
python scripts/simulation/teleop_dual_a1x_mujoco.py
89+
```
90+
91+
## Hardware teleoperation:
92+
- Robot definition files: only `.urdf` file is required
93+
- Config
94+
- link_name: the name of end effector link as defined in mujoco .xml & .urdf files
95+
- pose_source: name of the source of pose to be used by Pico client
96+
- control_trigger: the key to define whether an arm control is active
97+
- gripper_trigger: name of the key mapped to this gripper from the controller
98+
```python
99+
DEFAULT_END_EFFECTOR_CONFIG = {
100+
"left_arm": {
101+
"link_name": "left_tool0",
102+
"pose_source": "left_controller",
103+
"control_trigger": "left_grip",
104+
"gripper_trigger": "left_trigger",
105+
},
106+
"right_arm": {
107+
"link_name": "right_tool0",
108+
"pose_source": "right_controller",
109+
"control_trigger": "right_grip",
110+
"gripper_trigger": "right_trigger",
111+
},
112+
}
113+
```
114+
- Example code is provided for a lab setup with dual ur5e manipulators with robotiq 2f85 grippers, as well as a 2 DOF head controlled by 2 dynamixel motors.
115+
```bash
116+
python scripts/hardware/teleop_dual_ur5e_hardware.py
117+
```

0 commit comments

Comments
 (0)