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Movement Made To Measure

Immediate finding of solutions for car body kinematics using software-based, practically oriented, interactive methods of synthesis with the kinematics software ASOM v7.


  • Dipl.-Ing. Eliseo Milonia, info-key GmbH & Co. KG, Wuppertal


In this presentation, it will be shown how to perform a kinematics design from specification to solution in real-time (i.e. during the presentation itself), taking as example the process of designing a passenger car's rear tailgate mechanism. Using this example, several methods of synthesis are presented (kinematic synthesis, force synthesis and geometric synthesis). It is shown that all of these can be solved virtually in real-time for the given type of problem. This includes taking into account the usual requirements and restrictions that are specific to work on car bodies. The example assumes the use of a multi-bar linkage with at least one energy storage element (e.g. a specific predetermined gas spring). It is also shown how the kinematic design solution interactively adjusts whenever the specifications are modified.

It will be pointed out that using these methods, the developer or user is not forced into performing some kind of black box development. Quite the contrary: due to real-time graphical feedback and compressed-time-analyses, it is very easy for the user to keep track of the kinematics solution as a whole and of how any alterations are affecting it.

Since the underlying software solution is not an integral part of traditional CAD tools yet, a concept for integration into typical pre-existing development environments is briefly presented as well.

Lastly, it is shown

  • how these solutions can be generalized to other kinematic challenges (prismatic joints, six-bar linkages, serially connected syntheses, etc.),
  • how additional individual requirements can be integrated into it, and
  • how company-specific internal know-how can be taken into account.

The two core competencies of info-key


Q-Mining automatically looks for and finds solutions to increase the quality of your products and processes


ASOMv7 automates the synthesis of moving systems and finds solutions for kinematic problems like seating, hatches, lids, folding top systems, etc.

ASOM := Analysis, Synthesis and Optimization of Multi-bar linkages


ASOMv7 is a kinematics synthesis software for linkages with several unique features. The development of sophisticated kinematic product groups (such as kinematics with motors, hand forces, gas springs, etc.) is extremely simplified compared to the use of CAD software.

This is achieved, among other things, by a fundamentally different approach to such problems.

The user/developer describes in ASOM, intuitively but precisely, their requirements such as layers and/or desired force curves etc. ASOM then assists the developer in finding the desired solutions in an intuitive and interactive way.

Even Shorter

­ASOM := movement made to measure

What are the applications of ASOM?

  • The practically relevant, real time analysis, synthesis and optimization of multi-bar linkages
  • Finding accurate solutions of complex 2D kinematics problems
What are the applications of ASOM?

Short description of the steps for generating a kinematic solution with ASOM in 12 minutes

  • interfaces, data import
  • position requirements ➜ kinematic synthesis
  • determining forces
  • gas spring requirements ➜ desired gas spring
  • force requirements (desired forces at defined positions)
  • modifications while requirements are kept satisfied
  • data export
  • notes
ASOMv7 Sample problem: kinematic concept for a decklid

ASOMv7 Sample problem: kinematic concept for a decklid

  • desired opened/closed positions
  • restriction zones for four-bar joints and gas spring connectors
  • desired type of gas spring (e.g. specific model)
  • desired manual force value at specific opening angle
  • requirements to be met are:
    • lid positions,
    • restriction zones,
    • gas spring properties and
    • specific manual force values
  • ... to be met even during subsequent manual changes.
ASOMv7 Sample problem: Summery

ASOMv7 Sample problem: Summary

  • Conceptual solution for the most important design points
  • … with required starting and ending positions of the lid,
  • … observing the restriction zones,
  • … with desired gas spring,
  • … with desired manual force,
  • … while at the same time allowing for the consideration of further requirements like e.g. kinematics of opening and closing, gas spring tolerances and friction terms, comparison to case without gas spring, collisions with or without offset, etc.,
  • … with the option to make further modifications at any time, without violating the set requirements,
  • … with the option to capture and store your own know-how as custom expressions, to maintain and expand it for later use.


Common concept
  • The concept can be used for many typical kinematic problems for very diverse kinematics in the automobile industry (hatches, hoods, seating mechanics, interiors, folding top systems, etc.).
Time save
  • The time needed to design kinematic solutions is significantly reduced.
Design environment
  • Despite the assisted design ASOM is not a black box but – quite to the contrary – a completely open and real time interactive tool that assists the designer in expanding their own expertise.
Conceptual solutions
  • Completely new and innovative concepts can easily be implemented.
Expert knowledge
  • You can implement your expert knowledge in the form of physical or kinematic rule systems into the software, but it will ultimately remain your own.
Expertise for others to see
  • You will be able to easily demonstrate your kinematic expertise to your clients in an intuitive fashion.

Published in

Automotive Circle, Doors and Closures in Car Body Engineering 2015, 

6th International Benchmarking Conference with Innovation Award

Bad Nauheim, 17./18. November 2015

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