Configuration

The X500 needs no configuration: every slot the parts declare fills itself with its default. The loadout config (x500_description/config/x500.yaml, or any file passed as config_file:=) states differences only.

Payload

Sensors and actuators are fitted into slots, one config entry each. The fitted options and their topics live in Sensors and Actuators; the slots are:

Slot	Accepts	Default
rotor_0 .. rotor_3	the matching 1345 propeller	fitted
battery	battery_4s	fitted
gps	gps_mast	fitted
companion	companion_computer	empty
gimbal	gimbal_camera	empty

Keep the rotor instances named rotor_0 .. rotor_3: the motor command bus indexes actuators by that number, and the expansion fails loudly on a rotor whose name does not end in its actuator number. Slot entries, free placements, ad hoc slots and topic overrides follow the schema in Reference; the instance key is of:, not on:. Mistakes fail the build or the launch with a message naming the problem.