Template Class ActuationModelFloatingBaseThrustersTpl

Defined in File floating-base-thrusters.hpp

Inheritance Relationships

Base Type

public crocoddyl::ActuationModelAbstractTpl< _Scalar > (Template Class ActuationModelAbstractTpl)

Class Documentation

template<typename _Scalar> class ActuationModelFloatingBaseThrustersTpl : public crocoddyl::ActuationModelAbstractTpl<_Scalar>

Actuation models for floating base systems actuated with thrusters.

This actuation model models floating base robots equipped with thrusters, e.g., multicopters or marine robots equipped with manipulators. It control inputs are the thrusters’ thrust (i.e., forces) and joint torques.

Both actuation and Jacobians are computed analytically by calc and calcDiff, respectively.

We assume the robot velocity to zero for easily related square thruster velocities with thrust and torque generated. This approach is similarly implemented in M. Geisert and N. Mansard, “Trajectory generation for

quadrotor based systems using numerical optimal control”, (ICRA). See Section III.C.

Public Types

typedef MathBaseTpl<Scalar> MathBase

typedef ActuationModelAbstractTpl<Scalar> Base

typedef ActuationDataAbstractTpl<Scalar> Data

typedef StateMultibodyTpl<Scalar> StateMultibody

typedef ThrusterTpl<Scalar> Thruster

typedef MathBase::Vector3s Vector3s

typedef MathBase::VectorXs VectorXs

typedef MathBase::MatrixXs MatrixXs

Public Functions

EIGEN_MAKE_ALIGNED_OPERATOR_NEW CROCODDYL_DERIVED_CAST (ActuationModelBase, ActuationModelFloatingBaseThrustersTpl) typedef _Scalar Scalar

inline ActuationModelFloatingBaseThrustersTpl(std::shared_ptr<StateMultibody> state, const std::vector<Thruster> &thrusters)

Initialize the floating base actuation model equipped with thrusters.

Parameters:

state – [in] State of the dynamical system
thrusters – [in] Vector of thrusters

virtual ~ActuationModelFloatingBaseThrustersTpl() = default

inline virtual void calc(const std::shared_ptr<Data> &data, const Eigen::Ref<const VectorXs>&, const Eigen::Ref<const VectorXs> &u) override

Compute the actuation signal and actuation set from its thrust and joint torque inputs \(\mathbf{u}\in\mathbb{R}^{nu}\).

Parameters:

data – [in] Floating base thrusters actuation data
x – [in] State point \(\mathbf{x}\in\mathbb{R}^{ndx}\)
u – [in] Joint-torque input \(\mathbf{u}\in\mathbb{R}^{nu}\)

inline virtual void calcDiff(const std::shared_ptr<Data> &data, const Eigen::Ref<const VectorXs>&, const Eigen::Ref<const VectorXs>&) override

Compute the Jacobians of the floating base thruster actuation function.

Parameters:

data – [in] Floating base thrusters actuation data
x – [in] State point \(\mathbf{x}\in\mathbb{R}^{ndx}\)
u – [in] Joint-torque input \(\mathbf{u}\in\mathbb{R}^{nu}\)

inline virtual void commands(const std::shared_ptr<Data> &data, const Eigen::Ref<const VectorXs>&, const Eigen::Ref<const VectorXs> &tau) override

inline virtual void torqueTransform(const std::shared_ptr<Data> &data, const Eigen::Ref<const VectorXs>&, const Eigen::Ref<const VectorXs>&) override

inline virtual std::shared_ptr<Data> createData() override

Create the floating base thruster actuation data.

Returns:: the actuation data

template<typename NewScalar> inline ActuationModelFloatingBaseThrustersTpl<NewScalar> cast() const

inline const std::vector<Thruster> &get_thrusters() const: Return the vector of thrusters.

inline std::size_t get_nthrusters() const: Return the number of thrusters.

inline void set_thrusters(const std::vector<Thruster> &thrusters)

Modify the vector of thrusters.

Since we don’t want to allocate data, we request to pass the same number of thrusters.

Parameters:: thrusters – [in] Vector of thrusters

inline const MatrixXs &get_Wthrust() const

inline const MatrixXs &get_S() const

inline virtual void print(std::ostream &os) const override

Print relevant information of the residual model.

Parameters:: os – [out] Output stream object

Protected Attributes

std::vector<Thruster> thrusters_: Vector of thrusters.

std::size_t n_thrusters_: Number of thrusters.

MatrixXs W_thrust_: Matrix from thrusters thrusts to body wrench.

MatrixXs Mtau_: Constaint torque transform from generalized torques to joint torque inputs

MatrixXs S_: Selection matrix for under-actuation part.

bool update_data_

std::size_t nu_: Dimension of joint torque inputs.

std::shared_ptr<StateAbstract> state_: Model of the state.