Release notes

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SusProg3D - Suspension by Design.

Windows 8.1 and Windows 10

Version 5.112B (Build 1420.1)

Updates and fixes in this release.
Version 5.112B (Build 1420.1)
Updated the bump steer calculation for struts.

Version 5.112A (Build 1418.0)
Added additional validation when using shock lengths to limit wheel travel.
Extended the Jacobs ladder to allow for multiple birdcage holes and unequal length sides.
If the torsion bar calculation fails, then show the position of the torsion bar with a dash line.

Version 5.110A (Build 1415.0)
Updated the CMM tool and added a caster rotation input.
Added an option to allow metric dimensions to 3 decimal places and inch dimensions to 4 decimal places.
Updated the axis setting input to enable changing the axis sequence.
Updated all inputs that have tabs and highlighted the active tab.
Fixed the corrupted help file topics when using styles.

Version 5.108B (Build 1399.1)
Corrected the travel calculations when using shock lengths and bellcranks.
Corrected the CMM tool to update both LH and RH tyre radius if symmetrical.
Corrected the turning radius and turning circle calculations to allow for larger king pin offsets.

Version 5.108A (Build 1399.0)
Updated and corrected the anti-roll bar rate calculations.
References used are the SAE Spring Design Manual and Chassis Design Principles and Analysis.
Updated and extended the travel calculations when using shock lengths.
Corrected the front suspension caster calculation for virtual A-arms.
Updated to the latest Delphi 10.4.2 Sydney compiler.

Version 5.106E (Build 1393.4)
The coil spring calculator tool sometimes corrupted data when switching between Metric and Imperial units. Fixed.

Version 5.106D (Build 1386.3)
The coil spring calculator tool didn't read all specified inputs. Fixed.

Version 5.106C (Build 1386.2)
When using inch dimensions the ride height input showed 2 decimal places instead of 3. Fixed.
Corrected a rear suspension caster calculation error in the CMM tool.

Version 5.106B (Build 1383.1)
Corrected the spring seat dimension when specifying the spring free length.
Added the units to the rates section of the antirollbar input form.

Version 5.106A (Build 1380.0)
Updated all the Excel interface tools.
Individual worksheet names can now be specified for front and rear, left and right.
Specified worksheet names are now read from, and saved back to, the workbook.
The Excel tools can now interface with VCalc and read and write the complete vehicle.
Added a workaround to support a 3-link live axle with a single bottom link (undocumented).

Version 5.104B (Build 1370.1)
Fixed a bug with the suspension dialog that sometimes prevented the LH/RH symmetrical checkbox showing.
Corrected a bug that incorrectly assigned the AllWheelDrive property.

Version 5.104A (Build 1367.0)
Added the bellcrank antirollbar for 4-link live axle.
Fixed the "Invalid variant type" and "Range check error" bug in Calc2Excel.
Included both input and calculated wheel alignment and instant centre data in the geometry results.
Added the driveshaft calculations in roll for deDion axles.
Corrected the anti-squat calculations for deDion axles.

Version 5.102B (Build 1356.1)
Add a lower link shock absorber for trailing arm and lateral link geometry.
Fixed the OfficeXPrt270.bpl load error.

Version 5.102A (Build 1355.0)
Revised the trailing arm with upper and lower lateral links wheel alignment and instant centre calculation for improved accuracy and performance.
Updated to the latest Delphi 10.4.1 Sydney compiler.

Version 5.100C (Build 1353.2)
Recompiled to exclude testing Assertions
Fixed a bug preventing the opening of a data file with a leaf spring

Version 5.100B (Build 1352.1)
With a new file, setting the ride heights failed. Fixed
Switching the spring units (N/mm <> lb/in) corrupted the wheel rates. Fixed
Specifying a spring rate didn't back calculate the wheel rate and frequency. Fixed

Version 5.100A (Build 1350.0)

SusProg3D now available in 64-bit.
For all supported versions of Windows 64-bit.
A small performance improvement has been found compared to the 32-bit version.

Added the functionality to input parameters to generate a 4th order polynomial to calculate the tyre radius and the contact patch centroid offset.
The required parameters are the tyre radius and contact patch centroid offset at zero camber, static camber and maximum camber.

Added a stop ring for primary and secondary coil springs. The position of the stop ring controls the transition point from the initial spring rate to the final spring rate.
Changed the spring calculation to use frequency or wheel rate to calculate the spring rate.
Removed an unnecessary Calc button and combined the spring calculation into the usual Apply button.

Excel input and output now include all four ride heights and reference points.
Previously if you were working with the front or rear suspension, then only the ride heights and reference points for that end were included. Now both ends are included.

Excel output now allows for specifying separate bump and droop, roll and turn sections.
Previously all data was in one section. This now makes it easier to export just the sections of interest.

When specifying a front suspension with both top and bottom A-arms with "virtual pivots", the calculated and specified caster can differ by a small amount.
To correct this, adjust the entered caster until the calculated caster equals the required caster.

Using File | New caused an exception. Fixed.

Version 4.670C (Build 1301.2)
Corrected an error in reading antirollbar data for some rear suspension geometries.

Version 4.670B (Build 1301.1)
Portal axles released.
Added an axis indicator to the bottom left corner of the graphic.
If using a dual rate spring, and the tender spring rate is zero, raise an error message instead of causing a "Floating point division by zero" error.

Version 4.670A (Build 1297.0) (Pre-release)
Portal axles added. This is a pre-release version available for testing.
It will install into a separate folder to the production release version so that you can run and compare both versions.
But, any data file saved with this version cannot be opened with any previous version, so work with a copy of your data file.

V4.664D (Build 1274.3)
If there was no previous file history, then opening the first file raised an error.

V4.664C (Build 1274.2)
If the spring calculation results in a negative spring length, then raise an error.
Added additional error reporting to eCalc and vCalc where a single module doesn't calculate correctly.
Added the Porsche 718 K inclined trailing arm pivot axis.

V4.664B (Build 1268.1)
When using ECalc or VCalc, for some live axle rear suspensions the spring rates didn't get calculated if there was no driveline.

V4.664A (Build 1268.0)
Added the Volkswagen Beetle twin trailing link suspension and steering.
Updated to the latest Delphi 10.3.2 Rio compiler.

V4.662A (Build 1265.0)
Fixed a bug that sometimes caused live axle links to be deleted in error.
Added a lever arm style shockabsorber.
Added a live axle mounted rack and pinion steering.
Added additional bellcrank items for Input2Excel and Excel2Input.

V4.660G (Build 1258.6)
Fixed a bug in the spring, shock, arb suspension input form that displayed incorrect text.

V4.660F (Build 1258.5)
Fixed a bug in the server licence registration that ignored the entered port number.
Fixed a bug in the network client that erroneously reported a registered client as unregistered.
Added the functionality to allow entering vehicle coordinates for axle mounted shock and spring.
Fixed a bug that displayed an incorrect axis character in some input forms.

V4.660E (Build 1254.4)
Fixed a bug with the steering calculations when using [Upright].
Fixed a bug with the roll calculations if there was zero bump travel.
Added an error check for invalid shock lengths if they were used to set suspension travel.
Fixed a bug with showing steering tab items when there was no steering.
Updated the ECalc and VCalc to show more meaningful error messages.

V4.660C (Build 1253.2)
Fixed a bug with the live axle 4-link suspension.
Added better error handling for excessive turning angle with lateral drag link steering.

V4.660B (Build 1252.1)
Updated the roll&bump calculations to include static.

V4.660A (Build 1252.0)
Extensive changes to the live axle calculations for performance.
Reduced the number of live axle calculation options.


Your suggestions and comments are appreciated.
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Please include the version and build number (in the SusProg3D About box) and operating system.