The latest version 5.01 of the WinGeo3
suspension geometry program includes the Expert suite of programs.
This version includes the Parts menu which permits uprights and
a-arms to be measured off the car in their own coordinate system and then
assembled into a suspension. This is more accurate than trying to measure
the center of a rotation of a ball joint. This reflects the way stock car
teams build suspensions.
The Expert suite of programs includes the
SetupAarm and SetupRear programs which permit the analysis of
camber shims, caster slugs and anti-dive slugs. This simple program produces
a camber curve allowing the race engineer to achieve a desired camber angle
at a specific ride and roll target.
WinGeo analyses automotive
suspensions. The program will determine how camber, toe, scrub, roll
center, etc., change as the vehicle moves through different combinations
of ride height, body roll, or steering inputs. The user can also change
the alignment (by shims or other adjustment) and see the effect on camber,
caster and bumpsteer.
The program allows the user to rapidly and accurately
study a suspension design or setting. The user may move the chassis using
the keyboard arrows and quickly see the consequences on the screen. The
program displays the computed suspension parameters on the screen as well
as a graphical view of the vehicle. The program also shows how the
parameter is determined.
The WinGeo3 5.01 Geometry program now comes in three versions:
Advanced $495 -
Full three-dimensional kinematic analysis of Double A-Arm and
MacPherson Strut suspensions. Analyze up to five different suspensions. The
user can move the chassis to a particular point or run through a range
of motion. A ride iteration
would compute suspension parameters for a variety of ride heights. This
would produce a graph of bump steer. A roll iteration would produce a
graph of roll center movement as a function of chassis roll. A steering
iteration would produce a plot of net steer and Ackerman at different
program will compute the suspension values for a given set of ride,
roll, steer and pitch. The user may also enter spring or shock
displacement and calculate the chassis position that produces those
values. This is useful if you have data on suspension travel. The user
may also specify chassis clearance. This is useful for studying the
effect of setup changes. For instance, you might measure the car on a
flat plate. But when the car goes to pit lane the team will record
chassis clearance values. These can be entered into the program to
calculate the corresponding chassis ride and roll values.
In addition to Double A-arm and MacPherson Strut suspension you can also
analyze solid rear-axle suspensions with a Panhard rod and five-link
independent suspensions (often called Multi-Link).
The Fixture allows the user to measure the points of the
hub on a measuring device and then attach the hub in a specific position
by specifying camber, toesteer, caster and track. This is an essential
tool for stock car teams.
The Build menu allows the user to manipulate
existing parts by changing tire size, track or other parameters. The Design
menu allows the user to create a suspension from desired suspension
parameters. The user may specify caster and kingpin and Instant Center
location and the program will design a suspension with those
The Table feature permits the user to run the
suspension through a range of motion and produce a table of suspension
values. The range of motion might be ride height and the table would
show bump steer. Or it might be the path a car takes through a turn so
you can study suspension movement through the turn.
The Solve for Steering permits the user to
specify a steer value and calculate the steering input that produces
that steering value.
version will also handle third springs and five-link independent
Expert $895 - This
version was introduced in November, 2008. This is the Advanced version
plus the Parts menu which permits the user to assemble a suspension from
parts and to adjust that suspension accurately.
This version was previously available for $345. But most of the few
customers who purchased in this 2005 upgraded to the Advanced version
within one month. The Advanced version offers many more features and is
a better buy.
Premier/Data or Grand Prix / Data $1,895 –
Load data and compute suspension for any point on the track. The data
may be in a MATLAB file, an ASCII comma-separated variable or
blank-separated variable and must include speed, lateral G, steering and
Tire Deflection – Specify a vertical tire
deflection rate for the tire (spring rate) and the program will compute
a tire deflection proportional to the load from the springs and swaybars.
With many modern cars having 50% of their suspension travel in the
tires, this analytical tool is vital for proper analysis. There is also
a special report for understanding the effect of different tire spring
Fundamental Analysis –
Compute camber and scrub movement from instant center location.
Derivative Analysis – Compute Instant Center locations from
camber and scrub calculations.
Rising Rate – Compute rising rate values for spring
Anti-Dive, Anti-Squat, Sideview Swingarm – additional analysis
of anti- properties.
This plot shows a race car from the rear looking
towards the front. This is the driver's view of the front suspension. The
car is turning left; has rolled one degree and moved 0.5 inches below pit
lane ride height. The right tire has 0.439 degrees of camber and the left
tire -0.964 degrees.The right spring has compressed 0.613 inches and the
right shock 0.531 inches.The antiroll bar has twisted 5.071 degrees. The
right tire has toesteer of 0.021 degrees to the left and the left tire has
zero toesteer. The right side instant center is 2.919 inches above
ground and the left is 5.112 inches. The roll center has moved 5.980 inches
to the left of the centerline and is 1.136 inches above ground.