Unit 07 · lesson
Bridge Checkpoint: Identity Changes Across Layers
Two systems may use similar names for related components without sharing identity.
A Java object reference, a WPILib subsystem instance, a ROS node name, and a physical device identifier can all point to different things.
Build an identity map for one robot component:
| layer | example identity | what it names |
|---|---|---|
| Java | frontRange variable | local object reference |
| WPILib | subsystem instance | framework component |
| ROS 2 | /sensor_bridge | graph entity |
| hardware | CAN/device ID | physical/controller endpoint |
Now mark which mappings are observed and which are merely intended.
Failure case
Suppose the Java variable is named sensorBridge and a ROS node is named /sensor_bridge. That naming similarity is not evidence that the object and node are connected.
What would prove the relationship? You need an actual bridge mechanism, interface, trace, or configuration path.
Deliverable
Write one identity claim that is safe and one that would be an overreach.
The bridge skill is keeping human-readable naming conventions separate from runtime identity evidence.