Partner in product development

With Vink System Design & Analysis I (Jaap Vink) provide engineering services to companies. I specialize in precision mechanics and am an experienced and result-oriented partner in the development of complex opto-mechanical and mechatronic systems where high accuracy is required.

To perform regular or specialist mechanical calculations and analyes, I have developed a toolkit with software programs and a spreadsheet. You can download and use these.

Engineering Toolkit

Spreadsheet Tolerance analysis

TolStackUp is a tolerance analysis spreadsheet (template) created in Microsoft Excel. It is designed to analyze and manage the impact of dimensional deviations of parts in an assembly.

Calculate Beam Deflection Pro

FlexBeam Pro is a user-friendly calculator for the deflection and buckling of beams. After filling in the data, FlexBeam Pro makes the necessary calculations.

Calculate Beam Deflection Lite

Do you want to try FlexBeam first or do you not need the more extensive functionality of FlexBeam Pro? Then download the free version FlexBeam Lite.

Calculate Hertz Contacts

With HertzWin you can quickly calculate point and line contacts. The practical, free program automatically performs all Hertzian contact calculations.

Calculate Flexure Hinges

With the free FlexHinge program, you can quickly calculate the stiffness and material stress of a flexure hinge. It performs all calculations automatically.


I’m using FlexBeam to support my classes as a mechanical design teacher at a Technical School – Javier, Spain

I have downloaded your program and have confirmed that your Hertz Contact Stress calculation matches what I have been using. I believe that HertzWin will be helpful in quickly checking my hand calculations – Michael, USA (Pennsylvania)

I can only be positive about FlexBeam, very practical! – Philippe, Belgium

I have been a user of your FlexHinge software for the past few years and have found it very useful – Joey, USA

We have tested FlexBeam Pro and are very happy with it – Jaap, The Netherlands

I would like to thank you for your program HerzWin. It is really easy to use it and it has really nice visualization – Frantisek, Czech Republic

Recent Posts

Rolling Contact Fatigue

Up to and including release 3.2.0 of HertzWin, all calculated results related to a static situation. The most important material stresses for a static situation are the maximum shear stress and the Von Mises equivalent stress. Most commonly used to determine whether a...

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Tangential Force Acting on a Hertzian Contact in HertzWin

With the program HertzWin you can calculate Hertz point and line contacts. The influence of a tangential force can also be calculated. HertzWin has been available online for free since March 2009. No approximation but the exact solution In older releases of HertzWin...

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Refined, Advanced Tolerance Analysis

In previous articles about tolerance analysis, I discussed the step-by-step plan and the way of adding up. Adding up tolerances can be a worst-case sum or a statistical sum. In 'The distribution of tolerances' I also discussed the types of distributions that may...

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