BuoyancyController Class Reference

Controller that compensates for buoyancy and gravity restoring forces. More...

#include <BuoyancyController.h>

Inheritance diagram for BuoyancyController:

Public Member Functions
void	reset () override
	Resets the adaptive buoyancy bias to zero. More...
Vector6d	getForce (const State &goal, const State &curr, double dt) override
	Computes the total buoyancy compensation force. More...
void	saveBias ()
	Saves the current adaptive bias for later restoration. More...
void	loadBias ()
	Restores the adaptive bias from the most recent saved snapshot. More...
double	getBias () const
	Returns the current adaptive bias value in Newtons. More...
	BaseControllerInterface ()=default
	BaseControllerInterface (std::shared_ptr< SystemDynamicsBase > auv, std::shared_ptr< ControllerConfig > config)
	Constructs a controller with the given dynamics model and config. More...
Public Member Functions inherited from BaseControllerInterface
	BaseControllerInterface ()=default
	BaseControllerInterface (std::shared_ptr< SystemDynamicsBase > auv, std::shared_ptr< ControllerConfig > config)
	Constructs a controller with the given dynamics model and config. More...
virtual	~BaseControllerInterface ()=default

Additional Inherited Members
Protected Attributes inherited from BaseControllerInterface
std::shared_ptr< SystemDynamicsBase >	auv_
	Vehicle dynamics model shared with all controllers in a stack. More...
std::shared_ptr< ControllerConfig >	config_
	Tuning parameters shared with all controllers in a stack. More...

Detailed Description

Controller that compensates for buoyancy and gravity restoring forces.

Produces two additive components:

1. Static model-based compensation — the gravitational/buoyancy restoring wrench G(q) evaluated at the goal orientation, identical to the original behaviour.
2. Adaptive bias estimation (opt-in via buoyancy_adaptive) — a slow integrator on the heave axis that learns the residual buoyancy force not captured by the static model. The bias is only updated when the vehicle is in approximate steady state (small depth error and small heave velocity), so it does not fight the PD controller during transients. Inspired by the adaptive feedforward in Eng You Hong et al., "Depth Control of an Autonomous Underwater Vehicle, STARFISH", NUS 2010.

Returns zero near the surface when surface gain scheduling is enabled.

Member Function Documentation

BaseControllerInterface() [1/2]

BaseControllerInterface::BaseControllerInterface

default

BaseControllerInterface() [2/2]

BaseControllerInterface::BaseControllerInterface

inline

Constructs a controller with the given dynamics model and config.

Parameters

auv	[in] Shared vehicle dynamics model
config	[in] Shared controller tuning parameters

getBias()

double BuoyancyController::getBias

(

)

const

Returns the current adaptive bias value in Newtons.

getForce()

Vector6d BuoyancyController::getForce ( const State &  goal, const State &  curr, double  dt  )

overridevirtual

Computes the total buoyancy compensation force.

Returns G(q) from the dynamics model plus, when adaptive estimation is enabled, an adaptive heave-axis bias that slowly tracks residual depth error during steady state.

Parameters

goal	[in] Desired vehicle state (orientation and position Z are used)
curr	[in] Current vehicle state (position Z and twist Z are used)
dt	[in] Time step in seconds (used by the adaptive estimator)

Returns

6-element restoring + adaptive force/torque vector in N and Nm

Implements BaseControllerInterface.

loadBias()

void BuoyancyController::loadBias

(

)

Restores the adaptive bias from the most recent saved snapshot.

reset()

void BuoyancyController::reset ( )

overridevirtual

Resets the adaptive buoyancy bias to zero.

Reimplemented from BaseControllerInterface.

saveBias()

void BuoyancyController::saveBias

(

)

Saves the current adaptive bias for later restoration.

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The documentation for this class was generated from the following files:

• include/controller/BuoyancyController.h
• src/controller/BuoyancyController.cpp