iDynTree::ContactStateMachine class
#include <iDynTree/ContactStateMachine.h>

Contact State Machine class for binary contact state detection Contains a Schmitt Trigger device for updating the contact states using the contact normal force acting on the contact link and Determines contact transitions using simple binary switching logic.

Can be used to determine stable contacts, contact breaking and contact making. The parameters to the Schmitt Trigger are passed as a struct and is the Schmitt Trigger is instantiated in the class constructor.

NOTE: There are no default parameters to the Schmitt Trigger. These parameters are set through the constructor during instantiation.

This class does not exactly abstract the Schmitt Trigger class. Schmitt Trigger methods are still accessible through the m_contactSchmitt object. This class uses a generic Schmitt Trigger object and augments its functionality specific to physical contacts based scenarios.

Public types

enum contactTransition { STABLE_OFFCONTACT, STABLE_ONCONTACT, CONTACT_BREAK, CONTACT_MAKE, UNKNOWN_TRANSITION = -1 }: Enumeration of contact transitions.

Constructors, destructors, conversion operators

ContactStateMachine(const SchmittParams& s): Constructor.

Public functions

void contactMeasurementUpdate(double currentTime, double contactNormalForce): Calls schmitt trigger device update.
void resetDevice(): Calls schmitt trigger device reset.
auto contactState() -> bool: Get current contact state.
auto contactTransitionMode() -> contactTransition: Determines contact transitions using simple binary switching logic.
auto lastUpdateTime() -> double: Get time of last contact state update.

Public variables

std::unique_ptr<SchmittTrigger> m_contactSchmitt: unique pointer to the schmitt trigger device

Enum documentation

enum iDynTree::ContactStateMachine::contactTransition

Enumeration of contact transitions.

Enumerators
STABLE_OFFCONTACT	previous state: off contact, current state: off contact
STABLE_ONCONTACT	previous state: on contact, current state: on contact
CONTACT_BREAK	previous state: on contact, current state: off contact
CONTACT_MAKE	previous state: off contact, current state: on contact
UNKNOWN_TRANSITION	Unknown transition.

Function documentation

iDynTree::ContactStateMachine::ContactStateMachine(const SchmittParams& s)

Constructor.

Parameters
s	const reference to a struct containing schmitt trigger device parameters

void iDynTree::ContactStateMachine::contactMeasurementUpdate(double currentTime, double contactNormalForce)

Calls schmitt trigger device update.

Parameters
currentTime	time
contactNormalForce	normal force acting on the contact link in consideration

bool iDynTree::ContactStateMachine::contactState()

Get current contact state.

Returns	true, if in contact, false otherwise

contactTransition iDynTree::ContactStateMachine::contactTransitionMode()

Determines contact transitions using simple binary switching logic.

Returns	contactTransition enumerated value

double iDynTree::ContactStateMachine::lastUpdateTime()

Get time of last contact state update.

Returns	time

iDynTree::ContactStateMachine class #include <iDynTree/ContactStateMachine.h>