Trying to add a gimbal results in error - and fix

[OdedHorowits]

Adding a gimbal to the aerostack2_examples/project_gazebo/sim_config/world.json file as seems at https://aerostack2.github.io/_03_aerial_platforms/_gazebo_simulation/index.html#gimbal results in error:

[ERROR] [launch]: Caught exception in launch (see debug for traceback):
field "payload" not yet prepared so type is still a ForwardRef, you might need to call Payload.update_forward_refs().

To fix that, there is a need to add the following line (with no indent) at the end of /opt/ros/humble/local/lib/python3.10/dist-packages/as2_gazebo_assets/models/payload.py:

Payload.update_forward_refs()

[pariaspe]

Hi @OdedHorowits , which Pydantic version are you using? Try to install Pydantic v1.10

[OdedHorowits]

Hi @pariaspe Using Pydantic v1.10, indeed there is no need for my addition. I had version 1.8.2 before. However, the camera attached to the gimbal is not streaming any data - Nothing is seen in rviz, and ros2 topic echo /drone0/sensor_measurements/rgbd_camera/camera_info gives nothing (on both versions of Pydantic)

[pariaspe]

Did that error msg disappear? There are some known bugs in aerostack2 v1.0.9 that hopefully will be solved soon in next release. Could you please share your new world.json?

[OdedHorowits]

The error msg is not presented anymore. Here is my world.json that does not stream any camera data:

{
    "world_name": "my_world",
    "drones": [
        {
            "model_type": "quadrotor_base",
            "model_name": "drone0",
            "xyz": [0.0, 0.0, 0.3],
            "rpy": [0, 0, 0],
            "flight_time": 60,
            "payload": [
                {
                    "model_type": "gimbal_position",
                    "model_name": "gimbal",
                    "payload":
                    {
                        "model_type": "rgbd_camera",
                        "model_name": "rgbd_camera"                        
                    }
                }
            ]
        }
    ]
}

This file work properly:

{
    "world_name": "my_world",
    "drones": [
        {
            "model_type": "quadrotor_base",
            "model_name": "drone0",
            "xyz": [0.0, 0.0, 0.3],
            "rpy": [0, 0, 0],
            "flight_time": 60,
            "payload": [
                {
                    "model_type": "rgbd_camera",
                    "model_name": "rgbd_camera",
                    "xyz": [0, 0, 0.2],
                    "rpy": [0, 0, 0]
                }
            ]
        }
    ]
}

[pariaspe]

Hi again, just tested it and it's working on main branch. Trying now on latest binary release

[pariaspe]

Hi @OdedHorowits, could you try launching the following json?

{
    "world_name": "my_world",
    "drones": [
        {
            "model_type": "quadrotor_base",
            "model_name": "drone0",
            "xyz": [0.0, 0.0, 0.3],
            "rpy": [0, 0, 0],
            "flight_time": 60,
            "payload": [
                {
                    "model_type": "gimbal_position",
                    "model_name": "gb",
                    "payload":
                    {
                        "model_type": "rgbd_camera",
                        "model_name": "rgbd_camera"                        
                    }
                }
            ]
        }
    ]
}

There was a hard-coded gimbal name somewhere in the code. As said before, it is already solved at main branch.

[OdedHorowits]

Hi @OdedHorowits, could you try launching the following json?

Yes, that fixed the problem. The gibal's model_name must be gb.

Here is how I installed Aerostack2 in my docker:

RUN apt-get update \
    && apt-get install -y \
      ros-humble-aerostack2 \
    && rm -rf /var/lib/apt-get/lists/*

RUN apt-get update \
    && apt-get install -y \
    ros-humble-as2-gazebo-assets \
    && rm -rf /var/lib/apt-get/lists/*

RUN apt-get update \
    && apt-get install -y \
    ros-humble-as2-platform-gazebo \
    && rm -rf /var/lib/apt-get/lists/* \
    && apt-get autoremove -y

Thtat gave me version 1.0.9-1jammy.20240530 So I hope that would be fixed in the next binaries version!

[pariaspe]

It will! Thanks for notifying the issue :+1:

[OdedHorowits]

Oh I am sorry... It works, but the streamed video vibrates as if there was no gimbal at all...

[pariaspe]

I'm sorry to say that vibration mitigation is not implemented yet in the gimbal

[OdedHorowits]

I'm sorry to say that vibration mitigation is not implemented yet in the gimbal

Oh, ok then.