wandelbots-nova (Python SDK)

This library provides an SDK for the Wandelbots NOVA API.

The SDK will help you to build your own apps and services on top of NOVA and makes programming a robot as easy as possible.

wandelbots-nova_simple_welding.mov

Prerequisites

• A running Nova instance (get access at wandelbots.com)
• Valid Nova API credentials
• Python >=3.10

🚀 Quick Start

See the examples for usage of this library and further examples: utilizing rerun as a visualizer

# Add the package to your pyproject.toml
wandelbots-nova = { version = ">=0.12", extras = ["nova-rerun-bridge"] }

# Download the latest robot models (depends on gltf-transform)
npm install -g @gltf-transform/cli
poetry run download-models

# Add credentials and instance to .env file
NOVA_API="https://your-instance.wandelbots.io"
NOVA_ACCESS_TOKEN="your-access-token"

from nova_rerun_bridge import NovaRerunBridge
from nova import Nova

# Connect to your Nova instance (or use .env file)
nova = Nova(
    host="https://your-instance.wandelbots.io",
    access_token="your-access-token"
)
bridge = NovaRerunBridge(nova)

# Setup visualization
await bridge.setup_blueprint()

# Setup robot
cell = nova.cell()
controller = await cell.ensure_virtual_robot_controller(
    "ur",
    models.VirtualControllerTypes.UNIVERSALROBOTS_MINUS_UR10E,
    models.Manufacturer.UNIVERSALROBOTS,
)

# Connect to the controller and activate motion groups
async with controller[0] as motion_group:
    home_joints = await motion_group.joints()
    tcp_names = await motion_group.tcp_names()
    tcp = tcp_names[0]

    # Get current TCP pose and offset it slightly along the x-axis
    current_pose = await motion_group.tcp_pose(tcp)
    target_pose = current_pose @ Pose((1, 0, 0, 0, 0, 0))

    actions = [
        jnt(home_joints),
        ptp(target_pose),
        jnt(home_joints),
    ]

    # Plan trajectory
    joint_trajectory = await motion_group.plan(actions, tcp)

    # Log a trajectory
    await bridge.log_trajectory(joint_trajectory, tcp, motion_group)

Installation

To use the library, first install it using the following command

pip install wandelbots-nova

Optional: Install with nova-rerun-bridge

We recommend installing the library with the nova-rerun-bridge extra to make usage of the visualization tool rerun. See the README.md for further details.

pip install "wandelbots-nova[nova-rerun-bridge]"

Or add to your pyproject.toml:

wandelbots-nova = { version = ">=0.12", extras = ["nova-rerun-bridge"] }

You need to download the robot models to visualize the robot models in the rerun viewer. This needs the NPM package ltf-transform installed on your machine. You can download the models by running the following command:

npm install -g @gltf-transform/cli
poetry run download-models

Usage

Import the library in your code to get started.

from nova import Nova

The SDK also includes an auto-generated API client for the NOVA API. You can access the API client using the api module.

from nova import api

Checkout the 01_basic and 02_plan_and_execute examples to learn how to use the library.

In the this directory are more examples to explain the advanced usage of the SDK. If you want to utilize rerun as a visualizer you can find examples in the nova_rerun_bride examples folder.

Development

To install the development dependencies, run the following command

poetry install

Formatting

poetry run ruff format
poetry run ruff check --select I --fix

Yaml Linting

docker run --rm -it -v $(pwd):/data cytopia/yamllint -d .yamllint .

Using Branch Versions For Testing

When having feature branches or forks, or might be helpful to test the library as dependency in other projects first. Poetry allows to pull the library from different sources. See the Poetry Doc for more information.

Poetry Version < 2:

wandelbots-nova = { git = "https://github.com/wandelbotsgmbh/wandelbots-nova.git", branch = "fix/http-prefix" }

Poetry Version >=2

wandelbots-nova @ git+https://github.com/wandelbotsgmbh/wandelbots-nova.git@fix/http-prefix

Environment Variables for NOVA Configuration

1. Copy the Template: Make a copy of the provided .env.template file and rename it to .env with cp .env.template .env.
2. Fill in the Values: Open the .env file in a text editor and provide the necessary values for each variable. The table below describes each variable and its usage.

Variable	Description	Required	Default	Example
NOVA_API	The base URL or hostname of the NOVA server instance.	Yes	None	https://nova.example.com or http://172.0.0.1
NOVA_USERNAME	The username credential used for authentication with the NOVA service.	Yes*	None	my_username
NOVA_PASSWORD	The password credential used in conjunction with NOVA_USERNAME.	Yes*	None	my_password
NOVA_ACCESS_TOKEN	A pre-obtained access token for NOVA if using token-based authentication.	Yes*	None	eyJhbGciOi...

Note on Authentication: You can authenticate with NOVA using either username/password credentials or a pre-obtained access token, depending on your setup and security model:

• If using username/password: Ensure both NOVA_USERNAME and NOVA_PASSWORD are set, and leave NOVA_ACCESS_TOKEN unset.
• If using an access token: Ensure NOVA_ACCESS_TOKEN is set, and leave NOVA_USERNAME and NOVA_PASSWORD unset.

Only one method should be used at a time. If both methods are set, the token-based authentication (NOVA_ACCESS_TOKEN) will typically take precedence.