multi_body_hub Class Reference

Rigid body with multiple reaction wheels. More...

#include <multi_body_central_hub.h>

Inherits dsim_model.

Public Member Functions
void	initialize_data ()
	Initialize outlets and output variables.
void	initialization_complete ()
	Finish initialization.
void	initialize_timestep ()
	Computation done prior to numerical integration.
void	rhs (double t, double jd)
	Computation done during numerical integration. More...
void	complete_timestep ()
	Computation done after numerical integration.
dsim_value	handle_message (const std::string &sender_path, const std::string &message_name, const dsim_value &argument)
	Handle force and torque messages. More...

Protected Attributes
Integrated States
dsim_variable	position_dsim
	object position
dsim_variable	velocity_dsim
	object velocity
dsim_variable	quaternion_dsim
	attitude quaternion ([scalar;x;y;z])
dsim_variable	bodyRate_dsim
	body rotational rates (rad/s)
Parameters
dsim_variable	spacecraft_name_dsim
	Spacecraft name.
dsim_variable	spacecraft_type_dsim
	Spacecraft type.
dsim_variable	inertiaAppendage_dsim
	Spacecraft type.
dsim_variable	rhoAppendage_dsim
	Appendage vector from the gimbal to the appendage center of mass.
dsim_variable	lambdaAppendage_dsim
	Appendage gimbal offset from the reference.
dsim_variable	unitVectorAppendage_dsim
	Appendage unit vector.
dsim_variable	massAppendage_dsim
	Appendage mass.
dsim_variable	mass_dsim
	dry mass (kg)
dsim_variable	centerOfMass_dsim
	object center of mass
dsim_variable	inertia_dsim
	rigid body inertia
dsim_variable	frame_dsim
	frame for initial conditions
dsim_variable	numberRWA_dsim
	Number of reaction wheels.
dsim_variable	indexRWA_dsim
	Index for the reaction wheels.
dsim_variable	indexGimbal_dsim
	Indices for the gimbals.
dsim_variable	state_dsim
	Rotation dynamics and kinematics state.
dsim_variable	angle_appendage_dsim
	Rotation dynamics and kinematics state.
dsim_variable	rate_appendage_dsim
	Rotation dynamics and kinematics state.
dsim_variable	rWARate_dsim
	Rotation dynamics and kinematics state.

Outputs
dsim_variable	totalMass_dsim
	total mass, including mass of children
dsim_variable	ang_momentum_dsim
	Angular momentum.
dsim_variable	acceleration_dsim
	object linear acceleration in body frame
dsim_variable	angular_acceleration_dsim
	Angular acceleration.

Detailed Description

Rigid body with multiple reaction wheels.

Models a spacecraft with a set of identical reaction wheels. The default wheel set is orthogonal + skew (4 wheels). The torque must be provide by a child model. The model accepts apply_force, apply_torque, and apply_rwa_torque messages during rhs().

Member Function Documentation

rhs()

void multi_body_hub::rhs	(	double	t,
		double	jd
	)

Computation done during numerical integration.

Quaternion kinematics and orbit derivative with wheels dynamics.

Uses qi_to_b_dot from the SCControl framework. Overwrites rigid_body's rhs without calling it.

References acceleration_dsim, angular_acceleration_dsim, position_dsim, state_dsim, totalMass_dsim, and velocity_dsim.

handle_message()

dsim_value multi_body_hub::handle_message	(	const std::string &	sender_path,
		const std::string &	message_name,
		const dsim_value &	argument
	)

Handle force and torque messages.

Handles these message:

• "apply_force"
• "apply_torque"
• "apply_rwa_torque"

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

• multi_body_central_hub.h
• multi_body_central_hub.cc