Vocabulary

This page is generated from mobiledsl.semantic.model.vocabulary; edit the code, not the page. It lists every name a program may use beyond the grammar's keywords, and what each takes. Numbers carry no unit: the parameter name carries it by suffix (_s seconds, _m metres, _rad radians, _mps metres per second).

Component types (.core)

A component type is the kind of part a program places. A part can be used as a type when its library entry lists the type under profiles; the type's category is the kind of physical thing the part must be, which decides what its entry declares (a wheel its radius, a chassis its connectors). The chassis takes only ref; every other component is placed by glue. A type exists only when the compiler acts on it: a chassis type has kinematics, a wheel type a contact model, a track type a belt the targets stand in for, a sensor type a simulated sensor and a use for its data, a motor ratings that bound its wheel, a battery and a motor driver ratings the power and command rules judge. Everything the compiler merely carries is an Attachment; the library entry says what the part is.

Type	Category	Meaning
Mecanum_four_wheel	chassis	Four mecanum wheels; holonomic.
Diff_drive	chassis	Four driven standard wheels, skid steer.
Diff_two_caster	chassis	Two driven standard wheels and a caster.
Tricycle	chassis	One steered, driven front wheel and two free rear wheels.
Ackermann	chassis	Two steered front wheels, two driven rear wheels; the front wheels may be driven too.
Omni_drive	chassis	Four omni wheels; holonomic.
Omni_three_wheel	chassis	Three omni wheels on a circle; holonomic.
Tracked	chassis	Two tracks, each driven on its own; skid steer.
Legged	chassis	Legs on servos, its own or Leg parts placed on it; stands on their feet, walks as its gait states.
Mecanum	wheel	A mecanum wheel.
Standard	wheel	A plain driven wheel.
Caster	wheel	A passive support wheel.
Omni_wheel	wheel	An omni wheel.
Track	track	A track as one part: a belt around its sprockets and road wheels. It mates by the hub that drives it and moves the base by the travel its part states per turn.
Motor	motor	A motor on a drive mount of the chassis, where the wheel glued onto its shaft is driven, or on a seat of the chassis whose driveline turns the wheels of other mounts; within the speed and torque its part states. Its command names the motor driver that drives it.
Battery	battery	A battery pack, placed by its glue as any part is; the parts whose power names it run on the voltage its part states.
MotorDriver	motor_driver	A board that drives motors: each motor without a bus from a channel of its own, within the current its part states, and motors that carry their driver over a bus it speaks.
Lidar	sensor	A planar laser scanner.
Lidar3D	sensor	A spinning multi-ring laser; its cloud marks obstacles and its middle ring can stand in for a planar laser.
Camera	sensor	An RGB camera.
DepthCamera	sensor	A depth camera; its cloud can stand in for a laser.
RGBD	sensor	A colour camera with a registered depth image; its cloud can stand in for a laser.
IMU	sensor	An inertial measurement unit.
Ultrasonic	sensor	A range finder that measures with sound in a narrow cone; its reading marks the costmaps' range layer.
Range	sensor	A range finder that measures with light (infrared or time of flight) in a narrow cone; its part states its range, cone and rate, and its reading marks the costmaps' range layer.
Bumper	sensor	A contact switch on the body; Check_contact on it reads what pressed it.
Attachment	attachment	A part the compiler carries but does not act on: an arm, a gripper, a tray. It adds mass and shape; the library entry says what it is.
Leg	leg	A leg of a Legged chassis that has none of its own: links on hinges its servos turn, ending in the feet it stands on; the chassis's gait walks it with the others.

Parameters of a chassis:

Parameter	Type	Required	Meaning
ref	string	yes	The library part id.

Parameters of a wheel, track, sensor, battery, or attachment:

Parameter	Type	Required	Meaning
ref	string	yes	The library part id.
glue	tuple of 6 or 7	yes	Where the part mates: a connector of the chassis or of a part already placed, (x, y, z, nx, ny, nz) or with a roll angle (x, y, z, nx, ny, nz, roll). The point and the unit normal are in the chassis frame; the part's connector is aligned to them.

Parameters of a motor:

Parameter	Type	Required	Meaning
ref	string	yes	The library part id.
glue	tuple of 6 or 7	yes	Where the part mates: a connector of the chassis or of a part already placed, (x, y, z, nx, ny, nz) or with a roll angle (x, y, z, nx, ny, nz, roll). The point and the unit normal are in the chassis frame; the part's connector is aligned to them.
power	@core/<battery or motor driver>	no	What the motor draws its power from. A motor without a bus is powered through the driver that commands it and needs no power beside command; one with a bus names its supply here.
command	@core/<motor driver>	no	The motor driver that commands the motor: from one of its channels, or over the motor's bus.

Parameters of a motor driver:

Parameter	Type	Required	Meaning
ref	string	yes	The library part id.
glue	tuple of 6 or 7	yes	Where the part mates: a connector of the chassis or of a part already placed, (x, y, z, nx, ny, nz) or with a roll angle (x, y, z, nx, ny, nz, roll). The point and the unit normal are in the chassis frame; the part's connector is aligned to them.
power	@core/<battery>	no	The battery the driver is fed by.

Chassis types

What each chassis type needs and what the assembled base can do. A mount is driven in one of three ways. A Motor sits on it, its glue equal to the chassis connector that the part's profile maps the mount to, with one wheel of an allowed type on the motor's shaft. Or the wheel sits on the mount itself and a Motor sits on a connector of the chassis whose driveline turns that mount. Or the wheel sits on a mount the type always drives and no motor is declared: the kit's motors are then part of its chassis, and the targets drive the wheel within no stated limits and say so. On a mount that does not drive, or on an optional mount with no motor, the wheel sits alone and rolls freely. A Caster wheel is passive and may sit on any other connector. Every mount is driven unless the table lists the driven ones; a mount listed as optional is driven or free, together with the others listed so. One motor turns one mount, or through a driveline one of the sets under shared drive. A mount that steers turns about the kingpin the chassis part declares on that connector. A Tracked base carries a Track where the others carry a wheel, on its two mounts, and they are driven the same two ways. A Legged base carries neither: its legs are its part's own links, or Leg parts placed on it when it has none of its own. It stands on their feet, where their servos hold them, and its part's gait says what its walking controller takes: it moves aside when the gait takes a speed aside, and turns in place when the gait takes a turn.

Chassis	Wheel mounts	Wheel type	Driven	Shared drive	Steered	Holonomic	Spins in place
Mecanum_four_wheel	front_left_wheel, front_right_wheel, rear_left_wheel, rear_right_wheel	Mecanum	all	none	none	yes	yes
Diff_drive	front_left_wheel, front_right_wheel, rear_left_wheel, rear_right_wheel	Standard	all	front_left_wheel + rear_left_wheel; front_right_wheel + rear_right_wheel	none	no	yes
Diff_two_caster	left_wheel, right_wheel	Standard	all	none	none	no	yes
Tricycle	front_wheel, rear_left_wheel, rear_right_wheel	Standard	front_wheel	none	front_wheel	no	no
Ackermann	front_left_wheel, front_right_wheel, rear_left_wheel, rear_right_wheel	Standard	rear_left_wheel, rear_right_wheel; optional: front_left_wheel, front_right_wheel	rear_left_wheel + rear_right_wheel; front_left_wheel + front_right_wheel; front_left_wheel + front_right_wheel + rear_left_wheel + rear_right_wheel	front_left_wheel, front_right_wheel	no	no
Omni_drive	front_left_wheel, front_right_wheel, rear_left_wheel, rear_right_wheel	Omni_wheel	all	none	none	yes	yes
Omni_three_wheel	front_wheel, rear_left_wheel, rear_right_wheel	Omni_wheel	all	none	none	yes	yes
Tracked	left_track, right_track	Track	all	none	none	no	yes
Legged	none: it stands on its feet	none	none	none	none	its gait's	its gait's

World (.world)

Entity types

Type	Meaning
Obstacle	Something the robot must not touch: touching it fails the run.
SupportSurface	A floor, ramp or pad the robot drives on; contact is expected.
Marker	A visual mark such as a line or a goal disc; no collision by default.

All entity types take the same parameters:

Parameter	Type	Required	Meaning
type	box, sphere, cylinder	no	A primitive shape; exactly one of type and ref.
ref	string	no	The id of a library object, shown by its mesh and colliding by the shapes its entry declares; exactly one of type and ref.
pos	tuple of 7	yes	World pose (x, y, z, qx, qy, qz, qw); no rotation is (x, y, z, 0, 0, 0, 1).
size	tuple of 3	no	Primitive dimensions (x, y, z) in metres; required with type, refused with ref.
is_static	bool	no	Fixed in place (default true). No target moves an entity: it states no mass to move it with, so false is refused.
collision	bool	no	Emits collision geometry (default depends on the type). An object that declares no collision cannot collide.

Scenario

Parameter	Type	Required	Meaning
ref	string	yes	The base environment: the id of a library environment, whose floor and entities the scenario takes, or empty for none.
ground_plane	bool	no	Lay the world's ground plane (default false). A world has one: this is refused where an environment of any of its scenarios brings its floor, or another scenario already lays it.

Goal

Parameter	Type	Required	Meaning
pose	tuple of 7	no	The goal pose (x, y, z, qx, qy, qz, qw); one of pose and target.
target	@world/<entity>	no	An entity whose pose is the goal; one of pose and target.

physics

Parameter	Type	Required	Meaning
gravity	tuple of 3	no	Gravity (x, y, z) in m/s^2.

spawn

Parameter	Type	Required	Meaning
robot	@core/<robot>	yes	The robot declared in the .core file.
pose	tuple of 7	yes	Where the robot starts, (x, y, z, qx, qy, qz, qw).

Task (.task)

Task

Parameter	Type	Required	Meaning
timeout_s	number	no	The whole task must finish within this many seconds.

Composites (take children)

Sequence

Run children in order; stop at the first failure.

No parameters.

Fallback

Run children in order; stop at the first success.

No parameters.

Parallel

Run children together.

Parameter	Type	Required	Meaning
policy	success_on_all, success_on_one	yes	When the parallel succeeds.

Decorators (take exactly one child)

Retry

Re-run the child until it succeeds, at most count times.

Parameter	Type	Required	Meaning
count	number	yes	Number of attempts.

Repeat

Run the child count times.

Parameter	Type	Required	Meaning
count	number	yes	Number of attempts.

Timeout

Fail the child if it runs longer than timeout_s.

Parameter	Type	Required	Meaning
timeout_s	number	yes	Seconds.

Inverter

Swap the child's success and failure.

No parameters.

Actions

Navigate

Drive to a goal, avoiding obstacles.

Parameter	Type	Required	Meaning
goal	@world/<goal or entity>	yes	A goal or an entity in the world.

Wait

Do nothing for a while.

Parameter	Type	Required	Meaning
duration_s	number	yes	Seconds.

Stop

Come to rest.

No parameters.

Spin

Turn in place.

Parameter	Type	Required	Meaning
angle_rad	number	yes	Signed angle in radians.

Advance

Drive straight ahead.

Parameter	Type	Required	Meaning
distance_m	number	yes	Distance in metres.
speed_mps	number	no	Speed in m/s.

BackUp

Drive straight back.

Parameter	Type	Required	Meaning
distance_m	number	yes	Distance in metres.
speed_mps	number	no	Speed in m/s.

Strafe

Drive sideways; needs a holonomic base.

Parameter	Type	Required	Meaning
distance_m	number	yes	Signed distance in metres; positive is left.
speed_mps	number	no	Speed in m/s.

Conditions

GoalReached

True when the robot is at the goal.

Parameter	Type	Required	Meaning
goal	@world/<goal or entity>	yes	A goal or an entity in the world.

DistanceTraveled

True once the robot has moved this far.

Parameter	Type	Required	Meaning
distance_m	number	yes	Distance in metres.

TimeExpired

True once this much time has passed.

Parameter	Type	Required	Meaning
duration_s	number	yes	Seconds.

Evaluate (.eval)

Check_vel

Joint speed in rad/s: the magnitude of every sample stays within the bounds.

Parameter	Type	Required	Meaning
target	@core/<component>	yes	The wheel or joint to observe.
min	number	no	Lower bound; at least one bound is required.
max	number	no	Upper bound; at least one bound is required.

Check_acc

Joint acceleration in rad/s^2, the difference of successive speed samples; every sample stays within the bounds.

Parameter	Type	Required	Meaning
target	@core/<component>	yes	The wheel or joint to observe.
min	number	no	Lower bound; at least one bound is required.
max	number	no	Upper bound; at least one bound is required.

Check_jerk

Joint jerk in rad/s^3, the second difference of the speed samples; every sample stays within the bounds.

Parameter	Type	Required	Meaning
target	@core/<component>	yes	The wheel or joint to observe.
min	number	no	Lower bound; at least one bound is required.
max	number	no	Upper bound; at least one bound is required.

Check_effort

Joint effort in N*m: the magnitude of every sample stays within the bounds.

Parameter	Type	Required	Meaning
target	@core/<component>	yes	The wheel or joint to observe.
min	number	no	Lower bound; at least one bound is required.
max	number	no	Upper bound; at least one bound is required.

Check_distance

Distance in metres from the robot (or source) to target: min bounds the closest approach over the run, max the distance when the task ends. The robot is measured from its recorded position, a part from a point of its own shape seen from above, its declared ground contacts aside: the middle of the rectangle around its box or hull, square to the chassis; the centre of a wheel; the middle of a track's run on the ground where the track declares no shape; the part's origin where it declares no collision.

Parameter	Type	Required	Meaning
target	@world/<goal or entity>	yes	The entity or goal measured to.
source	@core/<component>	no	The robot part measured from.
min	number	no	Lower bound; at least one bound is required.
max	number	no	Upper bound; at least one bound is required.

Check_clearance

Distance in metres from the robot (or source) to the nearest obstacle, at its closest over the run.

Parameter	Type	Required	Meaning
target	@world/<goal or entity>	no	The obstacle to measure to; every obstacle when absent or not an obstacle.
source	@core/<component>	no	The robot part measured from.
min	number	no	Lower bound; at least one bound is required.
max	number	no	Upper bound; at least one bound is required.

Check_contact

Seconds the robot part target spends touching a scene entity: what its contact switch reports when it is a Bumper, else the simulator's geometry.

Parameter	Type	Required	Meaning
target	@core/<component>	yes	The robot part.
source	@core/<component>	no	The robot part measured from.
min	number	no	Lower bound; at least one bound is required.
max	number	no	Upper bound; at least one bound is required.

Check_time

Duration of the task in seconds, from its first tick to its last.

Parameter	Type	Required	Meaning
target	@task/<task>	yes	The task.
min	number	no	Lower bound; at least one bound is required.
max	number	no	Upper bound; at least one bound is required.