frcsim::DragModel Class Reference

Evaluates drag force on a moving body using quadratic and linear drag models. More...

#include <drag_model.hpp>

Public Member Functions
	DragModel (double drag_coefficient, double reference_area_m2, double air_density_kgpm3=1.225, double linear_drag_coefficient_n_per_mps=0.0)
	Constructs a drag force model.
Vector3::DragForceDetails	computeForceDetailed (const Vector3 &velocity_mps) const
	Computes detailed drag force breakdown for a world-space velocity vector.
Vector3::DragForceDetails	computeForceDetailed (const RigidBody &body) const
	Computes detailed drag force using body geometry and motion.
Vector3	computeForce (const Vector3 &velocity_mps) const
	Computes drag force vector for a world-space velocity.
Vector3	computeForce (const RigidBody &body) const
	Computes drag force using body geometry.
DragGravityComparison	compareToEffectiveGravity (const RigidBody &body, const Vector3 &effective_gravity_mps2) const
	Compares drag force magnitude against an effective gravity vector.
void	apply (RigidBody &body) const
	Applies computed drag force to a rigid body.

Detailed Description

Evaluates drag force on a moving body using quadratic and linear drag models.

The drag force is computed as quad + linear from Vector3::dragForce(). Useful for validating aerodynamic behavior and comparing against gravity.

Constructor & Destructor Documentation

DragModel()

frcsim::DragModel::DragModel ( double drag_coefficient, double reference_area_m2, double air_density_kgpm3 = 1.225, double linear_drag_coefficient_n_per_mps = 0.0 )

inline

Constructs a drag force model.

Parameters

drag_coefficient	Dimensionless drag coefficient (typically 0.1–2.0).
reference_area_m2	Reference area in square meters (cross-section).
air_density_kgpm3	Air density in kg/m^3 (default: 1.225 at sea level).
linear_drag_coefficient_n_per_mps	Optional linear drag term in N/(m/s).

Member Function Documentation

apply()

void frcsim::DragModel::apply ( RigidBody & body ) const

inline

Applies computed drag force to a rigid body.

Parameters

body	Rigid body to apply drag force to; kinematic bodies are skipped.

compareToEffectiveGravity()

DragGravityComparison frcsim::DragModel::compareToEffectiveGravity ( const RigidBody & body, const Vector3 & effective_gravity_mps2 ) const

inline

Compares drag force magnitude against an effective gravity vector.

Parameters

body	Rigid body to evaluate using world-space velocity.
effective_gravity_mps2	World-space effective gravity vector in m/s^2 (e.g., gravity + Magnus).

Returns

Diagnostic comparison showing drag-to-gravity ratio.

computeForce() [1/2]

Vector3 frcsim::DragModel::computeForce ( const RigidBody & body ) const

inline

Computes drag force using body geometry.

Parameters

body	Rigid body to evaluate drag for using its world-space velocity.

Returns

Drag force vector in newtons.

computeForce() [2/2]

Vector3 frcsim::DragModel::computeForce ( const Vector3 & velocity_mps ) const

inline

Computes drag force vector for a world-space velocity.

Parameters

velocity_mps

World-space velocity in m/s.

Returns

Drag force vector in newtons.

computeForceDetailed() [1/2]

Vector3::DragForceDetails frcsim::DragModel::computeForceDetailed ( const RigidBody & body ) const

inline

Computes detailed drag force using body geometry and motion.

Parameters

body	Rigid body supplying world-space velocity and drag area geometry.

Returns

DragForceDetails with force, direction, and diagnostics.

computeForceDetailed() [2/2]

Vector3::DragForceDetails frcsim::DragModel::computeForceDetailed ( const Vector3 & velocity_mps ) const

inline

Computes detailed drag force breakdown for a world-space velocity vector.

Parameters

velocity_mps

World-space velocity in m/s.

Returns

DragForceDetails with force, direction, and diagnostic fields.

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

• src/main/driver/include/frcsim/aerodynamics/drag_model.hpp