Reference

Config schema

The vehicle config is one YAML document with these top level keys:

Key	Required	Meaning
base	yes	the root part everything hangs off
topic_namespace	no (x500)	prefix of every part topic: /<ns>/<name>/...
parts	no ([])	the parts to fit: slot entries and free placements
slots	no	extra mount points the parts do not declare themselves
extra_bridge_topics	no	appended verbatim to the generated bridge config

base takes type (required), name (default base_link) and collision (default true).

Fitting a part

Entries under parts: come in two shapes. A slot entry drops a part into a slot some part already declares; a free placement has no slot: key and bolts the part to a parent at a pose you give.

Key	Slot entry	Free placement
slot	the slot to fill	-
of	instance carrying the slot (default base_link)	-
parent	-	link to attach to (default the base)
type	an accepted type, or none to leave empty	required
name	default: the slot name	required
xyz, rpy	offset from the slot pose	xyz required, rpy optional
joint, axis, collision	optional	optional
topic, gz_topic, ros_topic, bridge	parts with topics only	parts with topics only

Instance names must be unique across the vehicle.

Warning

The instance key is of:, not on:. YAML reads a bare on as the boolean true, so the entry silently means something else.

Ad hoc slots

Entries under slots: add a mount point that no part declares, then fill it like any other: of (instance, default base_link), name, xyz, rpy, accepts, default, joint, collision.

Errors

A key outside the schema is reported as a typo rather than ignored, and the message names the offending key alongside the ones that were expected. Any error fails the build or the launch instead of producing a half assembled vehicle.

Parts catalog

Type	What	Notes
x500_airframe	X500 V2 frame kit as one body	the assembly root; declares every slot
prop_1345_ccw, prop_1345_cw	1345 propellers with motor bell	carry the drive table; continuous joints
battery_4s	4S LiPo pack	box placeholder
companion_computer	RPi 4 / Jetson class computer	box placeholder
gps_mast	GPS module on a mast	antenna frame carries the NavSat
gimbal_camera	A8 mini class gimbal camera	box placeholder

Topics

See the X500 Sensors and Actuators pages. /clock and /joint_states are always bridged; every part topic follows /<namespace>/<instance>/<suffix> on both sides.

Packages

Package	Purpose
holybro_parts	the part library, the assembly dispatcher and the config check
x500_description	the X500 assembled from the parts; RViz view
x500_gazebo	composed Gazebo model, worlds, sim launch, generated bridge