# Useful Nodes

This section covers useful nodes for working with [Perception System](https://renownedgames.gitbook.io/ai-tree/perception-system) from [Behaviour Tree](https://renownedgames.gitbook.io/ai-tree/basic/behaviour-tree).

{% content-ref url="../nodes/tasks/perception-system/detection-signal" %}
[detection-signal](https://renownedgames.gitbook.io/ai-tree/nodes/tasks/perception-system/detection-signal)
{% endcontent-ref %}