Static Ride Analysis

A quasi-static simulation during which the left and right suspension is exercised from jounce to rebound and various suspension 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 steering travel (mm/deg)
  • Jounce travel (mm)
  • Rebound travel (mm)

Task Description

An initial steering input is applied to the model while keeping the wheel center position at design height. This is followed by moving both the left and right suspension to jounce height simultaneously, followed by moving the suspension to rebound height and back to design height.

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