Tire

tire

Tire models and utilities.

AxleTireParameters dataclass

Separate tire coefficients for front and rear axle.

Parameters:

Name	Type	Description	Default
front	PacejkaParameters	Front-axle Pacejka coefficients.	required
rear	PacejkaParameters	Rear-axle Pacejka coefficients.	required

validate

validate() -> None

Validate both axle parameter sets.

Raises:

Type	Description
ConfigurationError	If front or rear coefficient sets are invalid.

PacejkaParameters dataclass

Pacejka lateral model coefficients and load-sensitivity behavior.

The lateral force model uses coefficients B, C, D, E in a Magic Formula style equation. D is treated as an effective friction coefficient at the current reference condition.

Parameters:

Name	Type	Description	Default
B	float	Pacejka stiffness factor (-).	required
C	float	Pacejka shape factor (-).	required
D	float	Peak friction-like factor at reference load (-).	required
E	float	Pacejka curvature factor (-).	required
reference_load	float	Reference normal load used by load sensitivity [N].	required
load_sensitivity	float	Linear scaling of effective friction with load deviation from reference (-/N).	required
min_mu_scale	float	Lower bound for load-scaled friction multiplier (-).	required

validate

validate() -> None

Validate physical and numerical constraints for coefficients.

Raises:

Type	Description
ConfigurationError	If any coefficient violates required bounds.

axle_lateral_forces

axle_lateral_forces(front_slip_angle: float, rear_slip_angle: float, front_axle_load: float, rear_axle_load: float, axle_params: AxleTireParameters) -> tuple[float, float]

Compute total front/rear axle lateral force for single_track-equivalent tires.

Parameters:

Name	Type	Description	Default
front_slip_angle	float	Front axle equivalent slip angle [rad].	required
rear_slip_angle	float	Rear axle equivalent slip angle [rad].	required
front_axle_load	float	Total front axle normal load [N].	required
rear_axle_load	float	Total rear axle normal load [N].	required
axle_params	AxleTireParameters	Front/rear Pacejka parameter sets.	required

Returns:

Type	Description
tuple[float, float]	Tuple (Fy_front, Fy_rear) with axle lateral forces [N].

default_axle_tire_parameters

default_axle_tire_parameters() -> AxleTireParameters

Create a default high-downforce race-car tire parameterization.

Returns:

Type	Description
AxleTireParameters	Front and rear Pacejka parameter sets tuned for a high-downforce car.

magic_formula_lateral

magic_formula_lateral(slip_angle: float | FloatArray, normal_load: float | FloatArray, params: PacejkaParameters) -> float | FloatArray

Evaluate lateral tire force with load-sensitive Pacejka coefficients.

Parameters:

Name	Type	Description	Default
slip_angle	float | FloatArray	Tire slip angle [rad].	required
normal_load	float | FloatArray	Tire normal load [N].	required
params	PacejkaParameters	Pacejka coefficient set.	required

Returns:

Type	Description
float | FloatArray	Lateral force [N]. Sign follows slip-angle sign.