# Simulation 3D Physics Vehicle

Implement controllable 6DOF vehicle 3D environment

• Library:
• Vehicle Dynamics Blockset / Vehicle Scenarios / Sim3D / Sim3D Vehicle / Components

## Description

The Simulation 3D Physics Vehicle block implements a controllable 10DOF vehicle in the 3D simulation environment, with a vertical DOF for each vehicle and 6DOF for the chassis.

To use the Simulation 3D Physics Vehicle block, ensure that the Simulation 3D Scene Configuration block is in your model. If you set the Sample time parameter of the Simulation 3D Physics Vehicle block to -1, the block uses the sample time specified in the Simulation 3D Scene Configuration block.

The block input uses the vehicle Z-down right-handed (RH) Cartesian coordinate system defined in SAE J6701. The coordinate system is inertial and initially aligned with the vehicle geometric center:

• X-axis — Along vehicle longitudinal axis, points forward

• Y-axis — Along vehicle lateral axis, points to the right

• Z-axis — Points downward

Tip

Verify that the Simulation 3D Scene Configuration block executes before the Simulation 3D Physics Vehicle block. That way, the Unreal Engine® 3D visualization environment prepares the data before the Simulation 3D Physics Vehicle block receives it. To check the block execution order, right-click the blocks and select Properties. On the General tab, confirm these Priority settings:

• Simulation 3D Scene Configuration0

• Simulation 3D Physics Vehicle-1

## Ports

### Input

expand all

Normalized steer angle, specified as a scalar. SteerCmd corresponds to the minimum and maximum range of the steering angle as determined by theFront wheel max steer angle and Rear wheel max steer angle parameters, respectively

Normalized acceleration torque request to the vehicle powertrain, specified as a scalar. The exact response will be characterized by the engine, transmission and other vehicle parameters.

Normalized deceleration torque request to the vehicle braking system, specified as a scalar. The exact braking response will be characterized by the engine, transmission and other vehicle parameters.

Gear input, specified as either 1, -1, or 0, with:

• 1 – Forward shift gear.

• -1 – Reverse gear.

• 0 – Neutral gear.

If manual shift mode is selected, then the vehicle will shift according to what the signal is, but the values listed will still apply. Any input set that doesn't correspond to a valid gear will be ignored.

### Output

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Bus signal containing these block values.

SignalDescriptionValueUnits
InertFrmCgDispXVehicle CG displacement along the earth-fixed X-axis

Computed

m
YVehicle CG displacement along the earth-fixed Y-axis

Computed

m

ZVehicle CG displacement along the earth-fixed Z-axis0m
VelXdotVehicle CG velocity along the earth-fixed X-axis

Computed

m/s

YdotVehicle CG velocity along the earth-fixed Y-axis

Computed

m/s
ZdotVehicle CG velocity along the earth-fixed Z-axis0m/s
psiRotation of the vehicle-fixed frame about the earth-fixed Z-axis (yaw)

Computed

BdyFrmCgVelxdotVehicle CG velocity along the vehicle-fixed x-axis

Computed

m/s
ydotVehicle CG velocity along the vehicle-fixed y-axis

Computed

m/s
zdotVehicle CG velocity along the vehicle-fixed z-axis0m/s
AngBeta

Body slip angle, β

$\beta =\frac{{V}_{y}}{{V}_{x}}$

Computed

rVehicle angular velocity about the vehicle-fixed z-axis (yaw rate)

Computed

AccaxVehicle CG acceleration along the vehicle-fixed x-axis

Computed

gn
ayVehicle CG acceleration along the vehicle-fixed y-axis

Computed

gn
azVehicle CG acceleration along the vehicle-fixed z-axis0gn
xddotVehicle CG acceleration along the vehicle-fixed x-axis

Computed

m/s^2
yddotVehicle CG acceleration along the vehicle-fixed y-axis

Computed

m/s^2
zddotVehicle CG acceleration along the vehicle-fixed z-axis0m/s^2
rdotVehicle angular acceleration about the vehicle-fixed z-axis

Computed

DCM

Direction cosine matrix

Computed

ForcesTiresFrntTiresLftFx

Front left tire force, along the vehicle-fixed x-axis

ComputedN
Fy

Front left tire force, along the vehicle-fixed y-axis

ComputedN
Fz

Front left tire force, along the vehicle-fixed z-axis

ComputedN
RghtFx

Front right tire force, along the vehicle-fixed x-axis

ComputedN
Fy

Front right tire force, along the vehicle-fixed y-axis

ComputedN
Fz

Front right tire force, along the vehicle-fixed z-axis

ComputedN
RearTiresLftFx

Rear left tire force, along the vehicle-fixed x-axis

ComputedN
Fy

Rear left tire force, along the vehicle-fixed y-axis

ComputedN
Fz

Rear left tire force, along the vehicle-fixed z-axis

ComputedN
RghtFx

Rear right tire force, along the vehicle-fixed x-axis

ComputedN
Fy

Rear right tire force, along the vehicle-fixed y-axis

ComputedN

SignalDescriptionVariableUnits
MtrMtrSpd

Applied drive shaft angular speed input

ωi

RPM

TransTransGearCmd

Commanded gear

Ncmd

N/A

TransGear

Engaged gear

N

N/A

The Info output parameter is optional.

Vehicle CG velocity along the vehicle-fixed x-axis, in m/s.

Vehicle CG velocity along the vehicle-fixed y-axis, in m/s.

Rotation of the vehicle-fixed frame about the earth-fixed Z-axis (yaw), in rad.

Vehicle angular velocity, r, about the vehicle-fixed z-axis (yaw rate), in rad/s.

## Parameters

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### Chassis

Specify the vehicle type. This table provides links to the vehicle dimensions.

Vehicle type SettingVehicle Dimensions
Muscle car

Muscle Car

Sedan

Sedan

Sport utility vehicle

Sport Utility Vehicle

Small pickup truck

Small Pickup Truck

Hatchback

Hatchback

Box truck

Box Truck

#### Dependencies

Selecting Custom enables parameters that allow you to import a custom mesh for your vehicle.

Select the color of the vehicle.

Name of vehicle. By default, when you use the block in your model, the block sets the Name parameter to SimulinkVehicleX. The value of X depends on the number of Simulation 3D Physics Vehicle and Simulation 3D Vehicle blocks that you have in your model.

Initial vehicle position specified by a 1-by-3 array, in m. Array elements are values along the Coordinate system parameter X-, Y-, and Z- axes, respectively.

Initial vehicle rotation specified by a 1-by-3 array, in rad. Array elements are values about the Coordinate system parameter X-, Y-, and Z- axes, respectively.

Vehicle mass, in kg. This value does not include the wheel masses.

Vehicle drag coefficient, dimensionless.

The vehicle track width refers to the distance between the wheels, or the axle length, specified in meters. This parameter is only used for custom mesh options.

Height of chassis used to calculate drag force, specified in meters.

Offset in center of mass, specified as a three element vector, in meters.

Scaling of inertia tensor, specified as a three element dimensionless vector.

### Powertrain and Driveline

Powertrain

Motor torque indices, in N·m. You can use these pre-transmission values to represent either an electric motor or a conventional engine.

Data Types: double

Motor speed breakpoints, in rpm.

Data Types: double

Max powertrain speed, in rpm. If you select an automatic transmission option, this value also corresponds to the normalized shift points used in the up and downshift logic.

Data Types: double

Powertrain rotational inertia, in kg·m2.

Data Types: double

Powertrain damping at full max torque request, in kg·m2/s.

Data Types: double

Powertrain damping at zero torque request, in gear, in kg·m2/s.

Data Types: double

Powertrain damping at zero torque request, in neutral, in kg·m2/s.

Data Types: double

Driveline

For both Limited Slip and Open differentials, the block implements a differential as a planetary bevel gear train. The block matches the driveshaft bevel gear to the crown (ring) bevel gear.

If you select Limited Slip, the block prevents one of the wheels from slipping by splitting the torque applied to the left and right axles. With different torque applied to the axles, the wheels can move at different angular velocities, preventing slip.

Implement rear wheel, front wheel, or all wheel drive.

Implement an automatic or manual transmission.

Note

A response is required for the GearCmd input even if Transmission type is set to Automatic.

Clutch slip torque, specified as a scalar in N·m.

Data Types: double

Time taken to complete a shift, specified as a scalar in s.

Data Types: double

Minimum time the transmission will stay in a newly selected gear to mitigate shift hunting, specified as a scalar in s.

Data Types: double

Normalized engine speeds with respect to the Max powertrain speed parameter, at which a shift up for forward gears will be initiated, specified as a scalar in s.

Data Types: double

Normalized engine speeds with respect to the Max powertrain speed parameter, at which a shift down for forward gears will be initiated, specified as a scalar in s.

Data Types: double

Gear ratios, dimensionless.

Note

At least one negative ratio is required for reverse gear. A neutral ratio is also required such that the length of the array should correspond to the number of forward gears plus two one for reverse and one for neutral.

Data Types: double

Gear number vector, dimensionless.

Data Types: double

Front to rear torque split ratio, dimensionless.

1 indicates 100% torque to the front, whereas 0 indicates 100% to the rear.

Final drive ratio, dimensionless. This is the post transmission ratio, typically found in a differential or final drive gearbox.

Data Types: double

### Steering and Brakes

Steering

Front wheel max steer angle, in radians. This is the absolute angle which the front wheels will turn with a -1 or 1 steer command input signal

Data Types: double

Rear wheel max steer angle, in radians. This is the absolute angle which the rear wheels will turn with a -1 or 1 steer command input signal

Data Types: double

Constant value of percent Ackerman, in percent. A value of 100 indicates an ideal Ackermann inside or outside steering adjustment, while 0 indicates a pure parallel steer adjustment.

Data Types: double

Maximum steering ratio breakpoints, dimensionless. This is the gain by which the steering command is affected by the vehicle speed brake points.

Data Types: double

Steering ratio speed breakpoints, in m/s. This is the vehicle forward speed break points used by the steer ratio gains.

Data Types: double

Brakes

Maximum front wheel torque, in N·m. This is the maximum braking torque applied to the front wheels corresponding to the normalized DecelCmd input.

Data Types: double

Maximum rear wheel torque, in N·m. This is the maximum braking torque applied to the rear wheels corresponding to the normalized DecelCmd input.

Data Types: double

Front wheels affected by handbrake.

Data Types: Boolean

Rear wheels affected by handbrake.

Data Types: Boolean

Enable handbrake input.

Data Types: Boolean

### Suspension, Wheels and Tires

Suspension

Front suspension force offset, specified as a scalar in meters.

Maximum front suspension compression or jounce, specified as a scalar in meters. Jounce is the upward movement or compression of suspension components.

Maximum front suspension extension or rebound, specified as a scalar in meters. Rebound is the downward movement or extension of suspension components.

Natural frequency of front suspension, in Hz. Suspension frequencies are the rate that a spring oscillates after applying a load (or hitting a bump).

Damping ratio of front suspension, dimensionless. Damping ratio is the coefficient of the damper at its peak level, where the vehicle will be in a completely stable state.

Rear suspension force offset, specified as a scalar in meters.

Maximum rear suspension compression or jounce, specified as a scalar in meters. Jounce is the upward movement or compression of suspension components.

Maximum rear suspension extension or rebound, specified as a scalar in meters. Rebound is the downward movement or extension of suspension components.

Natural frequency of rear suspension, in Hz. Suspension frequencies are the rate that a spring oscillates after applying a load (or hitting a bump).

Wheels

Front wheel mass, in kg.

Data Types: double

Front wheel damping, in N·m/s.

Data Types: double

Rear wheel mass, in kg.

Data Types: double

Rear wheel damping, in N·m/s.

Data Types: double

Tires

Front tire max lateral stiffness factor, dimensionless.

Data Types: double

Front tire lateral stiffness, dimensionless.

Data Types: double

Front tire longitudinal stiffness, dimensionless.

Data Types: double

Front tire max lateral stiffness factor, dimensionless.

Data Types: double

Rear tire lateral stiffness, dimensionless.

Data Types: double

Front tire longitudinal stiffness, dimensionless.

Data Types: double

Nominal friction scale, dimensionless.

Data Types: double

### Light Controls

Select whether to control the vehicle headlights. Use the enabled parameters to set the light parameters, including headlight intensity.

#### Dependencies

Selecting this parameter:

• Creates the input port Light controls

• Enables these light parameters.

LightsLight Parameters

• High beam intensity

• Low beam intensity

• High beam cone half angle

• Low beam cone half angle

Brake lights

Brake light intensity

Reverse lights

Reverse light intensity

Turn signal lights

• Turn signal light intensity

• Period

• Pulse width

Headlight color, specified as a normalized 1-by-3 vector of RGB triplet values.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: int8 | uint8

High beam intensity, in cd.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

Low beam intensity, in cd.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

High beam cone half angle, in rad.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

Low beam cone half angle, in rad.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

Pitch and yaw orientation of the left headlight beam orientation in the Z-down coordinate system, specified as a 1-by-2 vector, in rad. The first element of the vector, [1,1], is the pitch angle. The second element of the vector, [1,2] is the yaw angle.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

Pitch and yaw orientation of the right headlight beam orientation in the Z-down coordinate system, specified as a 1-by-2 vector, in rad. The first element of the vector, [1,1], is the pitch angle. The second element of the vector, [1,2] is the yaw angle.

#### Dependencies

To enable this parameter, select Enable light controls.

Brake Lights

Brake light intensity, in cd/m^2.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

Reverse Lights

Reverse light intensity, in cd/m^2.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

Turn Signal Lights

Turn signal light intensity, in cd/m^2.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

Turn signal light period, in s.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

Turn signal light pulse width, as a percent of the period.

#### Dependencies

To enable this parameter, select Enable light controls.

Data Types: double

### Sample Time

Sample time, Ts. The graphics frame rate is the inverse of the sample time.

### Ground Truth

Select to return location and orientation.

Data Types: Boolean

Select to return nominal vehicle state feedback

Data Types: Boolean

## References

[1] Vehicle Dynamics Standards Committee. Vehicle Dynamics Terminology. SAE J670. Warrendale, PA: Society of Automotive Engineers, 2008.

[2] Technical Committee. Road vehicles — Vehicle dynamics and road-holding ability — Vocabulary. ISO 8855:2011. Geneva, Switzerland: International Organization for Standardization, 2011.

## Version History

Introduced in R2022b