Datasets

Vehicle Parameters

Some of the driver controllers (Feedforward controllers, gear shift controller) need vehicle information. This information can be provided using datasets. If these controllers are not used, you do not need to populate this dataset. The graphical user interface automatically populates these datasets.

altair_driver_dataset_property_data_mv

Parameter	Type	Range	Comments
Vehicle Mass	Real	Value>0
Final drive ratio	Real	Value>0	Coupler ratio between drive coupler output and input shafts. Note that drive ratio is 3.7 in case of default RWD model and 1 in case of default FWD model. This value is not parameterized.
Transmission efficiency	Real	Value>0	Input omega/(output omega*Drive ratio).
Drive type	Option	Value = FWD or RWD	Four wheel drive not allowed for advanced driver.
Max. powertrain torque	Real	Value > 0	Torque produced by the powertrain at the input shaft of the differential at 100% throttle. *Required only for vehicle models without CSE powertrain. Driver can directly query CSE powertrain.
Min. Powertrain torque	Real		Torque produced by the powertrain at the input shaft of the differential at 0% throttle. *Required only for vehicle models without CSE powertrain. Driver can directly query CSE powertrain.
Maximum front braking torque	Real	value>0	Maximum braking torque on front axle at 100.
Maximum rear braking torque	Real	Value>0	Maximum braking torque on rear axle.
Brake bias	Real	0<Value<1	Front to Rear. 0 is 100% front, 1 is 100% rear.
Front wheel radius	Real	Value>0	Loaded radius
Rear wheel radius	Real	Value >0	Loaded radius
Front cornering stiffness	Real	Value>0
Rear cornering stiffness	Real	Value>0
Vehicle a	Real	Value>0	X component (Vehicle SAE system) of the distance from vehicle front axle to vehicle CG.
Vehicle b	Real	Value>0	(Wheel base - vehicle a)
Vehicle yaw inertia	Real	Value>0
Steer ratio	Real	Value>0	Ratio of steering wheel input to tire motion (toe).

Analysis Settings

An Analysis settings dataset is required for user to give initial condition of the vehicle, simulation time and address of the Altair Driver file. This interface is a temporary data set and in the future these settings would go to Altair Driver file. The only thing that this data set would contain is the address of the Altair Driver file.

Parameter	Type	Range	Comments
Altair Driver file	File		Address of the file path

Signal Dimensions

A signal dimensions dataset is required to pass driver the information like Labels, ID, and dimensions of the end signals.

altair_driver_signal_dimensions_mv

Use Case:

$Example ADF end conditions block

(END_CONDITIONS)

{SIGNAL GROUP ABS OPERATOR VALUE TOLERANCE WATCH_TIME}

LONG_VEL 0 Y SS 0.0 0.0001 1.50

ROLL_ANGLE 1 Y SS 0.0 0.0001 1.50

PITCH_ANGLE 2 Y SS 0.0 0.0001 1.50

YAW_RATE 3 Y SS 0.0 0.0001 1.50

CG_Z 4 Y SS 0.0 0.0001 1.50

$------------------------------------------------------------------------------------------------------------------

Using this block in ADF and signals dimension dataset, Driver will know the appropriate conversion factors for each and every value.

Control States

The scripted driver works on the CSE architecture. A graphical user interface for CSE architecture is not supported, therefore one has to change MDL statements in order to make any changes.

MDL Statements
*GeneralStateEquation( gse_advanced_driver, "CSE Advanced Driver", 6, sa_u_advanced_driver, , )
gse_advanced_driver	Variable name of the driver cse.
“CSE Advanced Driver”	Label
6	Number of outputs.
sa_u_advanced_driver	Solver array with input signals.
	Driver resizes the state array and sets initial conditions of the states internally. Hence, the state IC array should not be provided.
*SetGeneralStateEquation( gse_advanced_driver, USER, `USER({sa_par0.idstring},1)` )
USER	Indicates that Motionsolve should look outside its dll’s for the entry point.
USER({sa_par.idstring})	Function call with par[0] = Array ID with vehicle parameters
*SetContinuousStates( gse_advanced_driver, 1 )
1	The number of states are by default set to 1.
*SetLocalUserDLL( gse_advanced_driver, "msautoutils" )
Msautoutils	Looks for this dll first in the current directory and then in Motionsolve installation.
*SetLocalUserFuncname( gse_advanced_driver, "SCRIPT_DRIVER" )
SCRIPT_DRIVER	Entry point function name.

Motions

Steering wheel motion	Driver computes the required steering angle and applies motion to the steering wheel joint.
Front and rear wheel motion	Required to lock the wheels during static simulation and lock the wheels.
Differential motion	Required to lock the differential during static.

Solver Arrays

These solver arrays are parameterized to data sets or attachments. You do not need to fill/edit them.

Mass Info Array

0 Reserved

1 Mass of the vehicle

Brake Info Array

0 Reserved

1 Max front braking torque

2 Max rear braking torque

3 Brake bias

4 Reserved

5 Reserved

Tire Info Array

0 Reserved

1 Front wheel loaded radius

2 Rear wheel loaded radius

3 1 if FWD 2 if RWD

4 Reserved

5 Reserved

Drag Info Array

0 Reserved

1 Air density

2 Drag coefficient

3 Frontal area

4 Reserved

5 reserved

Driver Info

0 Reserved

1 Altair Driver file path string ID

2 Solver array signals channel ID

3 Reserved

4 Reserved

Drive Train Info Array

0 Reserved

1 Final drive ratio

2 Transmission efficiency

3 Number of gears

4 Gear ratio 1

5 Gear ratio 2

6 Gear ratio 3

…..

14 Gear ratio 10

*If gear index, i > Number of gears, N

Gear Ratio [i] = Gear Ratio[N]

Bicycle Model Info Array

0 Reserved

1 Front cornering stiffness

2 Rear cornering stiffness

3 Vehicle a

4 Vehicle b

5 Yaw inertia

6 Steer ratio

7 Reserved

8 Reserved

Vehicle Parameters Array

0 Reserved

1 Mass info array ID

2 Brake info array ID

3 Drivetrain info array ID

4 Drag info array ID

5 Tire info array ID

6 0

7 Bicycle model array ID

8 Driver info array ID

9 Reserved

10 Reserved

Input Signal Array

0 Time

1 Longitudinal displacement

2 Lateral displacement

3 Vehicle heading angle

4 Vehicle longitudinal velocity

5 Vehicle lateral velocity

6 Yaw rate

7 Vehicle longitudinal acceleration

8 Vehicle lateral acceleration

9 Engine speed

11 Distance travelled

Signal channel

12 Signal 0

13 Signal 1

14 Signal 2

15 Signal 3

16 Signal 4

Control Entity Array

List of motion ID’s and Joint ID’s passed to driver for deactivation after running static analysis

0 Reserved

1 Steering wheel motion ID

2 Front left wheel motion ID

3 Front right wheel motion ID

4 Rear left wheel motion ID

5 Rear right wheel motion ID

6 Differential motion ID

*Required only if there is NO cse powertrain

7 J Prim 1 ID

8 J Prim 2 ID

9 sv_steer_angle ID

Solver Variables

Steer	Driver steer output -ARYVAL ( {driver_output_array_id }, 1 )
Throttle	Driver throttle output ARYVAL ( {driver_output_array_id }, 2 )
Brake	Driver brake output ARYVAL ( {driver_output_array_id }, 3 )
Gear	Driver gear output ARYVAL ( {driver_output_array_id }, 4 )
Clutch	Driver clutch output ARYVAL ( {driver_output_array_id }, 5 )
Distance traveled by the vehicle	DIF ( {diff_dis_travel.id} )
Longitudinal velocity wrt to gyro	-VX ( <Gyro fixed marker> , <Ground body CM marker> , < Gyro fixed marker > )
Lateral velocity wrt gyro	VY ( <Gyro fixed marker> , <Ground body CM marker> , < Gyro fixed marker > )
Yaw rate wrt gyro	WZ ( <Gyro fixed marker> , <Ground body CM marker> , < Gyro fixed marker > )
Longitudinal acceleration wrt gyro	-ACCX( <Gyro fixed marker> , <Ground body CM marker> , < Gyro fixed marker > )
Lateral acceleration wrt gyro	-ACCY( <Gyro fixed marker> , <Ground body CM marker> , < Gyro fixed marker > )
Engine speed	Engine speed attachment
Longitudinal displacement	DX ( <Vehicle Body>)
Lateral displacement	DY ( <Vehicle Body>)
Vehicle heading angle	AZ ( <Vehicle Body>)
Simulation time	TIME
Roll Angle	AX(<Vehicle Body>)
Pitch Angle	AY(<Vehicle Body>)
Roll Rate	WX(<Vehicle Body>, <Ground Body>, <Vehicle Body>)
Pitch Rate	WY(<Vehicle Body>, <Ground Body>, <Vehicle Body>)

Template

<ResOutput

plt_file = "TRUE"

PLT file is generated at the end of the simulation.

<DebugOutput

Switch_On = "FALSE"

Stat_Anim = "FALSE"

Writes out states of each and every component in the model.

Default = ‘FALSE’

Slows down the simulation speed if switched on.

<UserProgramControl

usrsub_param_string = "user(6454, {sys_tires.m_road_ref_frnt.l.id}, {advanced_driver.sa_deact_entities.id})"

usrsub_dll_name = "msautoutils"

usrsub_fnc_name = "RUN_DRIVER_EVENT"

CONSUB call to simulate transient and deactivate all the motions and joints after that.

Sensors

Maneuver switch

Switch to end one maneuver and start next maneuver. Sensor uses a sensor subroutine to monitor the signals and end conditions associated with the signal to actuate the switch.