Static Steer Analysis
A quasi-static simulation during which a steering input is applied to the model and various parameters are calculated.
Required input
Vehicle parameters:
- Tire static loaded radius (mm)
- Tire vertical spring rate (N/mm)
- Vehicle CG height (mm)
- Wheel base (mm)
- Front braking ratio
- Front drive ratio
- Axle ratio
- Vehicle weight (N)
Suspension and steering travel:
- Initial left wheel displacement (mm)
- Initial right wheel displacement (mm)
- Steering travel (mm/deg)
Task Description
An initial displacement is applied to the left and right suspension. This is followed by a steering movement during which a maximum positive and negative steering input is applied and various parameters are calculated.
Output
Reports containing some plots, tabular results, and graphical animation are automatically created.
The following parameters are calculated during the simulation and the results are written
to a text file (sdf.out). The same results are also written into the
request file as user requests.
- Wheel Center Displacement
- mm
- Ground Reaction Force
- N
- Toe-in
- deg
- Steer Angle
- deg
- Camber Angle
- deg
- Caster
- deg
- Kingpin Inclination
- deg
- Scrub Radius
- mm
- Caster Trail
- mm
- Roll Angle
- deg
- Tread Width
- mm
- Tread Change
- mm/m
- Track Width
- mm
- Wheel Center X Stiffness
- N/mm
- Wheel Center Y Stiffness
- N/mm
- Wheel Center Z Stiffness
- N/mm
- Wheel Center XX Stiffness
- N-m/deg
- Wheel Center YY Stiffness
- N-m/deg
- Wheel Center ZZ Stiffness
- N-m/deg
- Parallel Lateral Force Deflection
- mm/kN
- Converging Lateral Force Deflection
- mm/kN
- Parallel Lateral Force Steer
- deg/kN
- Converging Lateral Force Steer
- deg/kN
- Parallel Lateral Force Camber
- deg/kN
- Converging Lateral Force Camber
- deg/kN
- Parallel Aligning Torque Steer
- deg/100N-m
- Converging Aligning Torque Steer
- deg/100N-m
- Longitudinal Force Deflection @ Wheel center
- mm/kN
- Longitudinal Force Deflection @ Tire patch
- mm/kN
- Longitudinal Compliance Steer @ Wheel center
- deg/kN
- Longitudinal Compliance Steer @ Tire patch
- deg/kN
- Longitudinal Caster Compliance @ Wheel center
- deg/kN
- Longitudinal Caster Compliance @ Tire patch
- deg/kN
- Side View Swing Arm Length
- mm
- Side View Swing Arm Angle
- deg
- Side View Swing Arm Fore/Aft Location
- mm
- Side View Swing Arm Vertical Location
- mm
- Front View Swing Arm Length
- mm
- Front View Swing Arm Angle
- deg
- Front View Swing Arm Lateral Location
- mm
- Front View Swing Arm Vertical Location
- mm
- Ride Steer
- deg/m
- Ride Caster
- deg/m
- Ride Camber
- deg/m
- Roll Steer
- %
- Roll Caster
- %
- Roll Camber
- %
- Roll Inclination
- %
- Wheel Rate
- N/mm
- Ride Rate
- N/mm
- Hop Rate
- N/mm
- Suspension Roll Rate
- N-m/deg
- Total Roll Rate
- N-m/deg
- Tramp Rate
- N-m/deg
- Roll Center Height
- mm
- Roll Center Lateral
- mm
- Anti-lift
- %
- Acceleration Lift
- mm/g
- Anti-dive
- %
- Brake Dive
- mm/g
- Tractive Force Steer
- deg/g
- Tractive Force Windup
- deg/g
- Brake Steer
- deg/g
- Spindle Length
- mm
- Spindle Offset
- mm
- Ideal Steer Angle
- deg
- Curb to Curb Diameter 1
- m
- % Ackerman 1
- %
- Ackerman Deviation 1
- deg
- Curb to Curb Diameter 2
- m
- % Ackerman 2
- %
- Ackerman Deviation 2
- deg
- % Ackerman 3
- %
- Curb to Curb Diameter 4
- m
- % Ackerman 4
- %
- Ackerman Deviation 4
- deg
- Required input
- of task
-
Table 1. Parameter Units Wheel Center Displacement mm Ground Reaction Force N Toe-in deg Steer Angle deg Camber Angle deg Caster deg Kingpin Inclination deg Scrub Radius mm Caster Trail mm Roll Angle deg Tread Width mm Tread Change mm/m Track Width mm Wheel Center X Stiffness N/mm Wheel Center Y Stiffness N/mm Wheel Center Z Stiffness N/mm Wheel Center XX Stiffness N-m/deg Wheel Center YY Stiffness N-m/deg Wheel Center ZZ Stiffness N-m/deg Parallel Lateral Force Deflection mm/kN Converging Lateral Force Deflection mm/kN Parallel Lateral Force Steer deg/kN Converging Lateral Force Steer deg/kN Parallel Lateral Force Camber deg/kN Converging Lateral Force Camber deg/kN Parallel Aligning Torque Steer deg/100N-m Converging Aligning Torque Steer deg/100N-m Longitudinal Force Deflection @ Wheel center mm/kN Longitudinal Force Deflection @ Tire patch mm/kN Longitudinal Compliance Steer @ Wheel center deg/kN Longitudinal Compliance Steer @ Tire patch deg/kN Longitudinal Caster Compliance @ Wheel center deg/kN Longitudinal Caster Compliance @ Tire patch deg/kN Side View Swing Arm Length mm Side View Swing Arm Angle deg Side View Swing Arm Fore/Aft Location mm Side View Swing Arm Vertical Location mm Front View Swing Arm Length mm Front View Swing Arm Angle deg Front View Swing Arm Lateral Location mm Front View Swing Arm Vertical Location mm Ride Steer deg/m Ride Caster deg/m Ride Camber deg/m Roll Steer % Roll Caster % Roll Camber % Roll Inclination % Wheel Rate N/mm Ride Rate N/mm Hop Rate N/mm Suspension Roll Rate N-m/deg Total Roll Rate N-m/deg Tramp Rate N-m/deg Roll Center Height mm Roll Center Lateral mm Anti-lift % Acceleration Lift mm/g Anti-dive % Brake Dive mm/g Tractive Force Steer deg/g Tractive Force Windup deg/g Brake Steer deg/g Spindle Length mm Spindle Offset mm Ideal Steer Angle deg Curb to Curb Diameter 1 m % Ackerman 1 % Ackerman Deviation 1 deg Curb to Curb Diameter 2 m % Ackerman 2 % Ackerman Deviation 2 deg % Ackerman 3 % Curb to Curb Diameter 4 m % Ackerman 4 % Ackerman Deviation 4 deg