hydro_body::Wrench Struct Reference

The sum of the loads on a body: the force [0..2] and the moment about the origin [3..5], body frame.

#include <HydroBody.h>

Public Member Functions
void	Add (const double wrench[6])
	Adds the body-frame wrench wrench.
void	AddForceAt (const FlowFrame &frame, const double pos_d[3], const double force_n[3])
void	AddWeightAndBuoyancy (const FlowFrame &frame, double mass, const double cog_d[3], const double buoyancy_n[3])

Public Attributes
double	values [6] = {0.0, 0.0, 0.0, 0.0, 0.0, 0.0}

Member Function Documentation

AddForceAt()

void hydro_body::Wrench::AddForceAt	(	const FlowFrame &	frame,
		const double	pos_d[3],
		const double	force_n[3]
	)

Adds the NED force force_n acting at the body-frame point pos_d, and its moment.

Parameters

[in]	frame	The frame that rotates the force into the body frame.
[in]	pos_d	The point of attack, body frame [m].
[in]	force_n	The force, NED [N].

AddWeightAndBuoyancy()

void hydro_body::Wrench::AddWeightAndBuoyancy	(	const FlowFrame &	frame,
		double	mass,
		const double	cog_d[3],
		const double	buoyancy_n[3]
	)

Adds the weight mass * marenv::gravity at the body-frame point cog_d and the NED force buoyancy_n at the origin.

The weight is rotated into the body frame, its moment about the origin taken at cog_d, the buoyancy rotated and added into the same local wrench, and that wrench added once. This is not two AddForceAt calls: those add the weight and the buoyancy to the sum one by one, (w + g) + b, where this adds w + (g + b).

Parameters

[in]	frame	The frame that rotates the forces into the body frame.
[in]	mass	The mass of the body [kg].
[in]	cog_d	The centre of gravity, body frame [m].
[in]	buoyancy_n	The buoyancy force, NED [N], acting at the origin (so with no moment).

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The documentation for this struct was generated from the following file:

• webfhsim/reloadrepos/fhsim_base/src/body/HydroBody.h