Road Profile

Longitudinal profile of a road with varying elevation and friction properties.

Description

The Road Profile block represents a longitudinal road profile with varying height and friction properties. As the vehicle moves, the axle parameters and centre of gravity (CG) position determine the position of the front and rear axles. The block uses the axle positions to calculate the vehicle steering angle and tyre friction coefficients. The block models friction using either the empirical formula X. Paceika, or the coefficients of kinetic and static friction.

Variables

To set the priority and initial target values for block variables before the simulation starts, use the Initial Targets section of the block dialogue box.

Ports

Output

# beta — vehicle steering angle
scalar

Details

Output signal that sets the vehicle’s steering angle.

Data types	`Float64`.
Complex numbers support	No

# MF — front axle friction coefficients front axle friction coefficients for the friction model Magic Formula coefficients.
vector

Details

Output port that sets the friction coefficients of the front axle.

The vector contains four elements for the friction model Magic Formula coefficients.

Dependencies

To use this port, set the Friction output parameters to Magic Formula coefficients.

Data types	`Float64`.
Complex numbers support	No

# MR — vector of rear axle friction coefficients for the friction model Magic Formula coefficients
vector

Details

Output port that sets the rear axle friction coefficients.

The vector contains four elements for the friction model Magic Formula coefficients.

Dependencies

To use this port, set the Friction output parameters to Magic Formula coefficients.

Data types	`Float64`.
Complex numbers support	No

# MF — front axle friction coefficients for the friction model Friction coefficients
vector

Details

Output port that sets the friction coefficients of the front axle.

The vector contains two elements for the friction model Friction coefficients.

Dependencies

To use this port, set the Friction output parameters to Friction coefficients.

Data types	`Float64`.
Complex numbers support	No

# MR — vector of rear axle friction coefficients for the friction model Friction coefficients
vector

Details

Output port that sets the rear axle friction coefficients.

The vector contains two elements for the friction model Friction coefficients.

Dependencies

To use this port, set the Friction output parameters to Friction coefficients.

Data types	`Float64`.
Complex numbers support	No

Conserving

# H — horizontal movement
`translational mechanics'

Details

A non-directional port associated with horizontal motion.

Program usage name

flange

Parameters

Main

# Horizontal distance from CG to front axle — distance between centre of gravity and front axle
m | cm | ft | in | km | mi | mm | um | yd

Details

Horizontal distance from the centre of gravity to the front axle.

Units	`m` \| `cm` \| `ft` \| `in` \| `km` \| `mi` \| `mm` \| `um` \| `yd`
Default value	`1.4 m`
Program usage name	`front_axle_distance`
Evaluatable	Yes

# Horizontal distance from CG to rear axle — distance between centre of gravity and rear axle
m | cm | ft | in | km | mi | mm | um | yd

Details

Horizontal distance from the centre of gravity to the rear axle. Specify the same value as the Horizontal distance from CG to front axle parameters of the connected Vehicle Body block.

Units	`m` \| `cm` \| `ft` \| `in` \| `km` \| `mi` \| `mm` \| `um` \| `yd`
Default value	`1.6 m`
Program usage name	`rear_axle_distance`
Evaluatable	Yes

# Horizontal distance for vertical profile — horizontal distance of the vertical profile
m | cm | ft | in | km | mi | mm | um | yd

Details

An array of values corresponding to the distance by which the centre of gravity of the vehicle moves relative to the coordinate system -axis.

For example, the figure shows a horizontal profile [-10, 0, 10]. Extrapolation of tabular data is performed by the nearest value.

Units	`m` \| `cm` \| `ft` \| `in` \| `km` \| `mi` \| `mm` \| `um` \| `yd`
Default value	`[-10.0, 0.0, 10.0] m`
Program usage name	`position_vector`
Evaluatable	Yes

# Vertical profile — vertical profile
m | cm | ft | in | km | mi | mm | um | yd

Details

An array of values corresponding to the distance by which the vehicle’s centre of gravity moves relative to the coordinate system -axis.

For example, the figure shows a vertical profile [2, 0, 5]. Extrapolation of tabular data is performed by the nearest value.

Units	`m` \| `cm` \| `ft` \| `in` \| `km` \| `mi` \| `mm` \| `um` \| `yd`
Default value	`[0.0, 0.0, 0.25] m`
Program usage name	`height_vector`
Evaluatable	Yes

Friction

# Friction output — coefficient of friction
None | Magic Formula coefficients | Friction coefficients

Details

The coefficient of friction that the block outputs. Defined as:

None.
Magic Formula coefficients.
Friction coefficients

Dependencies

Setting the Friction output parameter to Magic Formula coefficients or Friction coefficients makes the MF and MR ports and their associated Friction parameters visible.

Values	`None` \| `Magic Formula coefficients` \| `Friction coefficients`
Default value	`None`
Program usage name	`friction_parameterization`
Evaluatable	No

# Horizontal distance for friction profile — horizontal distance for the friction profile
m | cm | ft | in | km | mi | mm | um | yd

Details

Horizontal distance of the friction profile.

Dependencies

To use this parameter, set the Friction output parameters to Magic Formula coefficients or Friction coefficients.

Units	`m` \| `cm` \| `ft` \| `in` \| `km` \| `mi` \| `mm` \| `um` \| `yd`
Default value	`[-10.0, 2.0, 2.1, 6.0, 6.1, 10.0] m`
Program usage name	`friction_vector`
Evaluatable	Yes

# Magic Formula coefficients for front axle — front axle coefficients

Details

The coefficients of the empirical formula X. Pacemakers given as a matrix to , where is the number of points in the vector Horizontal distance for friction profile.

Dependencies

To use this parameter, set the Friction output parameters to Magic Formula coefficients.

Default value	`[10.0 2.0 1.0 1.0; 10.0 2.0 1.0 1.0; 8.0 3.0 1.0 1.0; 8.0 3.0 1.0 1.0; 9.0 4.0 1.0 1.0; 9.0 4.0 1.0 1.0]`
Program usage name	`front_scaling_factor_matrix`
Evaluatable	Yes

# Magic Formula coefficients for rear axle — rear axle ratios

Details

The coefficients of the empirical formula X. Pacemakers given as a matrix to , where is the number of points in the vector Horizontal distance for friction profile.

Dependencies

To use this parameter, set the Friction output parameters to Magic Formula coefficients.

Default value	`[10.0 2.0 1.0 1.0; 10.0 2.0 1.0 1.0; 8.0 3.0 1.0 1.0; 8.0 3.0 1.0 1.0; 9.0 4.0 1.0 1.0; 9.0 4.0 1.0 1.0]`
Program usage name	`rear_scaling_factor_matrix`
Evaluatable	Yes

# Static and kinetic friction coefficients for front axle — friction coefficients of the front axle

Details

Front axle static and kinetic sliding friction coefficients, given as a matrix to , where is the number of points in the Horizontal distance for friction profile vector.

Dependencies

To use this parameter, set the Friction output parameters to Friction coefficients.

Default value	`[0.9 0.7; 0.9 0.7; 0.7 0.5; 0.7 0.5; 0.8 0.6; 0.8 0.6]`
Program usage name	`front_friction_coefficient_matrix`
Evaluatable	Yes

# Static and kinetic friction coefficients for rear axle — rear axle friction coefficients

Details

Static and kinetic rear axle sliding friction coefficients given as a matrix to , where is the number of points in the Horizontal distance for friction profile vector.

Dependencies

To use this parameter, set the Friction output parameters to Friction coefficients.

Default value	`[0.9 0.7; 0.9 0.7; 0.7 0.5; 0.7 0.5; 0.8 0.6; 0.8 0.6]`
Program usage name	`rear_friction_coefficient_matrix`
Evaluatable	Yes