Configure a Fake Arm

Configure a fake arm to test different models of robotic arms without any physical hardware.

Configure a fake arm as follows:

Config Builder
JSON Template

Creation of a fake ur5e arm in the Viam app config builder.

Note that this visual example sets the fake arm to act as a ur5e arm.

{
    "name": "<arm_name">",
    "type": "arm",
    "model": "fake",
    "attributes": {
        "arm-model": "<your_arm_model>"
        "model-path": "<your_arm_model_config_filepath>" // REMOVE if using arm-model
    }
}

The following attributes are available for fake arms:

Name	Inclusion	Description
`arm-model`	Optional	The name of the robotic arm model you want your fake arm to act as. This attribute must match the `name` of one of the arms Viam currently supports. See here for supported model names.
`model-path`	Optional	The path to a compatible Arm’s ModelJSON or URDF configuration file that you want your fake arm to act as. This path should point to the exact location where your configuration file is located on your computer running `viam-server`.

Caution

At least one of these attributes must be supplied for your fake arm to work. If neither are specified, an error is thrown asking for specification. If both attributes are specified, an error is thrown stating “can only populate either ArmModel or ModelPath - not both”.

Refer to the following JSON examples for differences in configuration between the two attributes available:

arm-model JSON Example
model-path JSON Example

{
    "name": "<arm-name">",
    "type": "arm",
    "model": "fake",
    "attributes": {
        "arm-model": "ur5e"
    }
}

{
    "name": "<arm-name">",
    "type": "arm",
    "model": "fake",
    "attributes": {
        "model-path": "/Users/<YOUR-USERNAME>/downloads/universalrobots/ur5e.json"
    }
}

Once you have successfully configured your fake arm, you can navigate to the CONTROL tab of the Viam app. A drop-down menu should appear with the name of your arm that allows you to toggle the fake arm’s joint positions and Cartesian end positions to dynamically test motion planning:

Motion planning remote-control of a fake ur5e arm in the Viam app control tab.

Note that this visual example sets the fake arm to act as a ur5e arm.