`unitree_mujoco` is a simulator developed based on `Unitree sdk2` and `mujoco`. Users can easily integrate the control programs developed with `Unitree_sdk2`, `unitree_ros2`, and `unitree_sdk2_python` into this simulator, enabling a seamless transition from simulation to physical development. The repository includes two versions of the simulator implemented in C++ and Python, with a structure as follows:
## Directory Structure
-`simulate`: Simulator implemented based on unitree_sdk2 and mujoco (C++)
-`simulate_python`: Simulator implemented based on unitree_sdk2_python and mujoco (Python)
-`unitree_robots`: MJCF description files for robots supported by unitree_sdk2
-`terrain_tool`: Tool for generating terrain in simulation scenarios
-`SportModeState`: Robot position and velocity data
Note:
1. The numbering of the motors corresponds to the actual robot hardware. Specific details can be found in the [Unitree documentation](https://support.unitree.com/home/zh/developer).
2. In the actual robot hardware, the `SportModeState` message is not readable after the built-in motion control service is turned off. However, the simulator retains this message to allow users to utilize the position and velocity information for analyzing the developed control programs.
You should see the mujoco simulator with the Go2 robot loaded.
In a new terminal, run:
```bash
./test
```
The program will output the robot's pose and position information in the simulator, and each motor of the robot will continuously output 1Nm of torque.
**Note:** The testing program sends the unitree_go message. If you want to test G1 robot, you need to modify the program to use the unitree_hg message.
You should see the mujoco simulator with the Go2 robot loaded.
In a new terminal, run:
```bash
python3 ./test/test_unitree_sdk2.py
```
The program will output the robot's pose and position information in the simulator, and each motor of the robot will continuously output 1Nm of torque.
**Note:** The testing program sends the unitree_go message. If you want to test G1 robot, you need to modify the program to use the unitree_hg message.
The simulator will use an Xbox or Switch gamepad to simulate the wireless controller of the robot. The button and joystick information of the wireless controller will be published through "rt/wireless_controller" topic. `use_joystick/USE_JOYSTICK` in `config.yaml/config.py` needs to be set to 0, when there is no gamepad. If your gamepad is not in Xbox or Switch layout, you can modify it in the source code (The button and joystick IDs can be determined using `jstest`):
In `simulate/src/unitree_sdk2_bridge/unitree_sdk2_bridge.cc`:
```C++
if (js_type == "xbox")
{
js_id_.axis["LX"] = 0; // Left stick axis x
js_id_.axis["LY"] = 1; // Left stick axis y
js_id_.axis["RX"] = 3; // Right stick axis x
js_id_.axis["RY"] = 4; // Right stick axis y
js_id_.axis["LT"] = 2; // Left trigger
js_id_.axis["RT"] = 5; // Right trigger
js_id_.axis["DX"] = 6; // Directional pad x
js_id_.axis["DY"] = 7; // Directional pad y
js_id_.button["X"] = 2;
js_id_.button["Y"] = 3;
js_id_.button["B"] = 1;
js_id_.button["A"] = 0;
js_id_.button["LB"] = 4;
js_id_.button["RB"] = 5;
js_id_.button["SELECT"] = 6;
js_id_.button["START"] = 7;
}
```
In `simulate_python/unitree_sdk2_bridge.py`:
```python
if js_type == "xbox":
self.axis_id = {
"LX": 0, # Left stick axis x
"LY": 1, # Left stick axis y
"RX": 3, # Right stick axis x
"RY": 4, # Right stick axis y
"LT": 2, # Left trigger
"RT": 5, # Right trigger
"DX": 6, # Directional pad x
"DY": 7, # Directional pad y
}
self.button_id = {
"X": 2,
"Y": 3,
"B": 1,
"A": 0,
"LB": 4,
"RB": 5,
"SELECT": 6,
"START": 7,
}
```
### Elastic band for humanoid
Consider humanoid robots are not suitable for starting in ground, a virtual elastic band was designed to simulate the lifting and lowering of humanoid robots. Setting ` enable_elastic_mand/ENABLE_ELSTIC_BAND=1 ` can enable the virtual elastic band. After loading the robot, press' 9 'to activate or release the strap, press' 7' to lower the robot, and press' 8 'to lift the robot.
We provide a tool to parametrically create simple terrains in the mujoco simulator, including stairs, rough ground, and height maps. The program is located in the `terrain_tool` folder. For specific usage instructions, refer to the README file in the `terrain_tool` folder.
## 3. Sim to Real
The `example` folder contains simple examples of using different interfaces to make the Go2 robot stand up and then lie down. These examples demonstrate how to implement the transition from simulation to reality using interfaces provided by Unitree. Here is an explanation of each folder name:
-`cpp`: Based on C++, using `unitree_sdk2` interface
-`python`: Based on Python, using `unitree_sdk2_python` interface
-`ros2`: Based on ROS2, using `unitree_ros2` interface
### unitree_sdk2
1. Compile
```bash
cd example/cpp
mkdir build && cd build
cmake ..
make -j4
```
2. Run:
```bash
./stand_go2 # Control the robot in the simulation (make sure the Go2 simulation scene has been loaded)
./stand_go2 enp3s0 # Control the physical robot, where enp3s0 is the name of the network card connected to the robot
```
3. Sim to Real
```cpp
if (argc <2)
{
// If no network card is input, use the simulated domain id and the local network card
ChannelFactory::Instance()->Init(1, "lo");
}
else
{
// Otherwise, use the specified network card
ChannelFactory::Instance()->Init(0, argv[1]);
}
```
### unitree_sdk2_python
1. Run
```bash
python3 ./stand_go2.py # Control the robot in the simulation (make sure the Go2 simulation scene has been loaded)
python3 ./stand_go2.py enp3s0 # Control the physical robot, where enp3s0 is the name of the network card connected to the robot
```
2. Sim to Real
```python
if len(sys.argv) <2:
// If no network card is input, use the simulated domain id and the local network card
ChannelFactoryInitialize(1, "lo")
else:
// Otherwise, use the specified network card
ChannelFactoryInitialize(0, sys.argv[1])
```
### unitree_ros2
1. Compile
First, ensure that the unitree_ros2 environment has been properly configured, see [unitree_ros2](https://github.com/unitreerobotics/unitree_ros2).
```bash
source ~/unitree_ros2/setup.sh
cd example/ros2
colcon build
```
2. Run simulation
```bash
source ~/unitree_ros2/setup_local.sh # Use the local network card
export ROS_DOMAIN_ID=1 # Modify the domain id to match the simulation
./install/stand_go2/bin/stand_go2 # Run
```
3. Run real robot
```bash
source ~/unitree_ros2/setup.sh # Use the network card connected to the robot
export ROS_DOMAIN_ID=0 # Use the default domain id
