Generators¶

Gait generators are used to create the contact phases needed for a gait.

GaitGenerator¶

namespace gambol

class GaitGenerator¶

#include <GaitGenerator.h>

Generates endeffector phase durations for predefined gait styles.

These gaits (e.g. quadruped trotting, biped walking) are used to initialize the towr optimization problem.

Subclassed by gambol::GaitGeneratorBiped, gambol::GaitGeneratorBipedFeet, gambol::GaitGeneratorMonoped, gambol::GaitGeneratorQuadruped, gambol::GaitGeneratorSnake

Public Types

enum Combos¶

Predefined combinations of different strides.

Values:

enumerator C0¶

enumerator C1¶

enumerator C2¶

enumerator C3¶

enumerator C4¶

enumerator COMBO_COUNT¶

enum Gaits¶

Predefined strides, each with a different gait diagram.

Values:

enumerator Stand¶

enumerator Flight¶

enumerator Walk1¶

enumerator Walk1B¶

enumerator Walk1E¶

enumerator Walk2¶

enumerator Walk2E¶

enumerator Walk3¶

enumerator Run2¶

enumerator Run2E¶

enumerator Run1¶

enumerator Run1E¶

enumerator Run3¶

enumerator Run3E¶

enumerator Hop1¶

enumerator Hop1E¶

enumerator Hop2¶

enumerator Hop3¶

enumerator Hop3E¶

enumerator Hop5¶

enumerator Hop5E¶

enumerator Balance¶

enumerator GAIT_COUNT¶

using Ptr = std::shared_ptr<GaitGenerator>¶

using VecTimes = std::vector<double>¶

using FootDurations = std::vector<VecTimes>¶

using ContactState = std::vector<bool>¶

using GaitInfo = std::pair<VecTimes, std::vector<ContactState>>¶

using EE = uint¶

Public Functions

GaitGenerator() = default¶

virtual ~GaitGenerator() = default¶

VecTimes GetPhaseDurations(double T, EE ee) const¶

Parameters

ee – endeffector for which the phase durations are desired.
T – total time for all phases, durations are scaled by that.

Returns

the swing and stance durations for the set gait.

std::vector<VecTimes> GetPhaseDurations(double T) const¶: Get phase durations for all end-effectors

bool IsInContactAtStart(EE ee) const¶

Parameters: ee – The endeffector/foot/hand.
Returns: true if the foot is initially in contact with the environment.

std::vector<bool> IsInContactAtStart() const¶: Get contac_at_start for all end-effectors

int GetSteps(EE ee = 0) const¶

Parameters: ee – The end-effector
Returns: Number of steps for a specific end-effector

virtual void SetCombo(Combos combo) = 0¶

Sets a specific sequence of gaits.

The derived class decides what each combo maps to. This function then fills the times_ and contacts_ variables accordingly.

void SetGaits(const std::vector<Gaits> &gaits)¶

Sets the times_ and contacts_ variables according to the gaits.

Parameters: gaits – The sequence of steps which defines gait. For example use {Stand,Walk1,Walk1,Stand} to declare walking gait with two steps.

Public Static Functions

static Ptr MakeGaitGenerator(int leg_count)¶

Protected Functions

GaitInfo RemoveTransition(const GaitInfo &g) const¶: Removes the last phase that would transition to a new stride. This is usually necessary for a gait change.

Protected Attributes

std::vector<double> times_¶: Phase times for the complete robot during which no contact state changes.

std::vector<ContactState> contacts_¶: The contact state for the complete robot. The size of this vector must be equal to the above times_.

Private Functions

FootDurations GetPhaseDurations() const¶

virtual GaitInfo GetGait(Gaits gait) const = 0¶

VecTimes GetNormalizedPhaseDurations(EE ee) const¶