OmniGraph Nodes with Wandelbots NOVA
Use OmniGraph Nodes in NVIDIA Isaac Sim with Wandelbots NOVA to simulate and connect IO signals. Add logic to your scenes using Action Graph for dynamic event-based control.
Connect IOs with your scene
The Wandelbots NOVA extension supports Action Graph, a visual scripting tool that adds logic to your NVIDIA Isaac Sim scenes. Action Graph uses OmniGraph nodes to enrich scenes with actions and reactions triggered by events.
With Action Graph, you can manipulate prim attributes to
- Toggle a conveyor belt,
- Change the emission of a texture (e.g., simulating a traffic light),
- Use trigger volumes to write the state of an IO on collision shape contact and many more.
Quickstart
Learn NVIDIA Isaac Sim Action Graph basics
Before using Wandelbots NOVA nodes, make sure you’re familiar with the Action Graph fundamentals.
Prepare simulation environment
To use one of the provided nodes, add a robot from the asset pack available in the Developer Portal download center or from Wandelbots’ GitHub. This robot serves as the configuration source for all data provided by the node.
Connect robot controller with NVIDIA Isaac Sim
Our OmniGraph Nodes require a established connection between Wandelbots NOVA and NVIDIA Isaac Sim. Therefore please connect your NVIDIA Isaac Sim instance with Wandelbots NOVA with the Connected Instances feature.
Use Robot Controller IOs
You can interact with robot controller IOs in your simulation using e.g. the Python SDK.
Alternatively you can also download the Signals App from the Store and set up IO signals via the Setup app. This allows you to trigger IOs without coding.
Use Bus IOs
After setting up everything correctly, you can then use e.g. the Python SDK or within the Setup app to trigger Bus IOs in your simulation. The simulation then will react based on your set up action graph similar to robot controller IOs.
Dive deeper into OmniGraph Nodes
Read through the sections below to get started with OmniGraph nodes (OGN). For additional resources, see further reads.
Robot controller IOs
Wandelbots NOVA provides a set of OmniGraph nodes to interact with robot controller signals in NVIDIA Isaac Sim.
Interact with the IOs of the robot controller used in your simulation. The Wandelbots NOVA extension provides three nodes to interact with robot controller IOs in Action Graph:
On IO Change Node
On IO Change provides an interface to trigger graph actions if the selected IO value changes.
This examples shows how an IO change triggers a write to a shared enable_conveyor variable and the change of a prim attribute
based on truthfulness.
Inputs
The node needs a running timeline to serve the requested IO data as well as a controller which is fetched from the robot controller root from the scene graph. The IO describes the IO which will be watched.
Outputs
The outputs are limited by the provided IO type. Make sure to connect the right output value type as this is the only one which gets updated.
Read IO Node
Read IO provides access to the current state of the selected IO.
This example shows how the IO value can be read every tick. The value then can be stored for later usage or to manipulate prims from the scene graph.
Inputs
The node needs a running timeline to serve the requested IO data as well as a controller which is fetched from the robot controller root from the scene graph. The IO describes the IO which will be watched.
Outputs
The outputs are limited by the provided IO type. Make sure to connect the right output value type as this is the only one which gets updated.
Write IO Node
Write IO allows the graph to manipulate the value of the selected virtual IO.
This example shows a trigger event which is attached to a physics trigger volume, like a light barrier.
Enter or Leave triggers the gate variable to be set which then changes the IO configured in Write IO.
Inputs
The node needs a running timeline to write an IO state as well as a controller which is fetched from the robot controller root from the scene graph. The IO describes the IO which will be written to.
Outputs
The inputs/outputs are limited by the provided IO type. Make sure to connect the right value type as this is the only one which gets read or updated.
Bus IOs
Wandelbots NOVA provides a set of OmniGraph nodes to interact with Bus signals, e.g., Profinet, in NVIDIA Isaac Sim.
Bus IOs are used to communicate with external devices via fieldbus protocols like Profinet. The Wandelbots NOVA extension provides three nodes to interact with Bus IOs in Action Graph:
On Bus IO Change Node
The On Bus IO Change node provides an interface to trigger graph actions if the selected IO value changes.
Inputs
The node needs a running timeline to serve the requested Bus IO data as well as a controller which is fetched from the robot controller root from the scene graph. The IO describes the IO which will be watched.
Outputs
The outputs are limited by the provided IO type. Make sure to connect the right output value type as this is the only one which gets updated.
Read Bus IO Node
Read Bus IO provides access to the current state of the selected Bus IO.
Inputs
The node needs a running timeline to serve the requested Bus IO data as well as a controller which is fetched from the robot controller root from the scene graph. The IO describes the IO which will be watched.
Outputs
The outputs are limited by the provided Bus IO type. Make sure to connect the right output value type as this is the only one which gets updated.
Write Bus IO Node
Write Bus IO allows the graph to manipulate the value of the selected virtual IO.
Inputs
The node needs a running timeline to write an IO state. It requires the information about the service which is fetched from the robot controller root from the scene graph. The Bus IO describes the Bus IO which will be written to.
Outputs
The inputs/outputs are limited by the provided Bus IO type. Make sure to connect the right value type as this is the only one which gets read or updated.
Further reads
Some of your burning questions have been left unanswered? Try out the search function or visit the FAQ page.