wa_simulator.controller

Classes

WAController	Base class for a controller
WAMatplotlibController	Controls a vehicle via keyboard input from a matplotlib figure
WAROS2Controller	Controller that communicates with a ROS2 control stack

class WAController(system: WASystem, vehicle_inputs: WAVehicleInputs)

Bases: wa_simulator.base.WABase

Base class for a controller

Controllers are responsible for outputting a steering, throttle and braking value. This is done because in real life, those are the inputs our cars will have. The derived controller’s (i.e. the new class that inherits from this class) responsibility is to take inputs from the simulation and return these values through the get_inputs method.

Parameters

• system (WASystem) – The system used to manage the simulation

• vehicle_inputs (WAVehicleInputs) – The vehicle inputs

Variables

• steering (float) – steering input.

• throttle (float) – throttle input.

• braking (float) – braking input.

abstract synchronize(self, time: float)

Update the state of this component at the current time.

The primary reason to decouple the update method into two separate calls (i.e. synchronize() and advance()) is to provide flexibility to the user and is essentially semantic. In most simple cases, a user will only need one of the two. Furthermore, can only use advance() if they prefer and just update their own time variable. Given the unknown use cases for the simulator at the time of writing, it was chosen to provide two different methods with similar functionality as to allow the user to choose their desired implementation, rather than the writers of this package.

As opposed to advance(), this method gets the current time of the simulation. As menthioned earlier, advance() and a user defined time variable could be used to instead to hold the current state of the simulation. However, to aid in generality of the package, this method is provided to simply provide the current time of the simulation to the user in a decoupled manner from the advance() method.

Parameters

time (float) – The current time to synchronize to

abstract advance(self, step: float)

Advance the state of this component by the specified time step.

The primary reason to decouple the update method into two separate calls (i.e. synchronize() and advance()) is to provide flexibility to the user and is essentially semantic. In most simple cases, a user will only need one of the two. Furthermore, can only use advance() if they prefer and just update their own time variable. Given the unknown use cases for the simulator at the time of writing, it was chosen to provide two different methods with similar functionality as to allow the user to choose their desired implementation, rather than the writers of this package.

Parameters

step (float) – The step size to advance this component by

is_ok(self) → bool

Check whether this component is still alive.

Depending the type of component, a specific element may “fail”. For example, when a visualization is used that presents a GUI/window, if the user closes that display, this would be considered a component death. Therefore, is_ok() should then return False.

Returns

bool – True if still alive, false otherwise

get_inputs(self) → WAVehicleInputs

Get the vehicle inputs

Returns

WAVehicleInputs – The input class

class WAMatplotlibController(system: WASystem, vehicle_inputs: WAVehicleInputs, vis: WAMatplotlibVisualization)

Bases: wa_simulator.controller._WAKeyboardController

Controls a vehicle via keyboard input from a matplotlib figure

Will asynchronously change inputs based on user input to the matplotlib window.

Parameters

• system (WASystem) – The system used to manage the simulation

• vehicle_inputs (WAVehicleInputs) – The vehicle inputs

• vis (WAMatplotlibVisualization) – The visualization that holds a matplotlib figure

synchronize(self, time)

Synchronize the controller at the specified time

Doesn’t do anything since this controller is completely asynchronous

Parameters

time (float) – the time at which the controller should synchronize all depends to

class WAROS2Controller(system: WASystem, vehicle_inputs: WAVehicleInputs)

Bases: wa_simulator.controller.WAController

Controller that communicates with a ROS2 control stack

Raises

ImportError – Will be raised if ROS 2 is not found on the system.

synchronize(self, time: float)

Update the state of this component at the current time.

The primary reason to decouple the update method into two separate calls (i.e. synchronize() and advance()) is to provide flexibility to the user and is essentially semantic. In most simple cases, a user will only need one of the two. Furthermore, can only use advance() if they prefer and just update their own time variable. Given the unknown use cases for the simulator at the time of writing, it was chosen to provide two different methods with similar functionality as to allow the user to choose their desired implementation, rather than the writers of this package.

As opposed to advance(), this method gets the current time of the simulation. As menthioned earlier, advance() and a user defined time variable could be used to instead to hold the current state of the simulation. However, to aid in generality of the package, this method is provided to simply provide the current time of the simulation to the user in a decoupled manner from the advance() method.

Parameters

time (float) – The current time to synchronize to

advance(self, step: float)

Advance the state of this component by the specified time step.

The primary reason to decouple the update method into two separate calls (i.e. synchronize() and advance()) is to provide flexibility to the user and is essentially semantic. In most simple cases, a user will only need one of the two. Furthermore, can only use advance() if they prefer and just update their own time variable. Given the unknown use cases for the simulator at the time of writing, it was chosen to provide two different methods with similar functionality as to allow the user to choose their desired implementation, rather than the writers of this package.

Parameters

step (float) – The step size to advance this component by