Analysis of the motion
of planar mechanisms

Kinematics, Dynamics, Optimization

Computer Program developed by
dr. Antonius J. Klein Breteler
(retired from TU Delft, Netherlands)

Originally the program has been developed to demonstrate some powerful algorithms of motion analysis and optimization of link dimensions. Original target group: the students of the TU Delft who need to do practical excercises in addition to studying the algorithms. The lecture notes of the former course (wb3303) can be downloaded for those who are interested: click here

After my retirement in 2005 the program Runmec (version 5.x) became then my personal toolbox for mechanism design.
In 2020 I started to develope a complete new version of Runmec that can be used by anyone who is aware of link mechanisms and needs an easy tool for investigating or demonstrating any (multi) link chain. Of course fully graphic "what you see is what you get" and all theoretical issues hidden as much as possible.

Runmec version 6.1 (released November 2023)  is available now. This version involves a complete kinematic analysis project of any multilink mechanism: build your own mechanism on the graphic screen, move it by dragging at any node, define a motion range for the Degree(s) Of Freedom, run the kinematics calculations, display animated motion and create graphs to include in your reports. Special attention has been given to attractive drawing of the moving mechanism: the user can select/adapt various shape models for all types of elements. This Runmec version can be considered also as the digital equivalent of the physical mechanism collection of the TU Delft. The picture above shows an example (mechanism model 24).  

Intentionally there is no detailed user manual: the program assumes intuitive use just supported by some help text. There is however a tutorial that describes briefly the capabilities of the program and that intends to guide the user actions and achievements. 

Download of RUNMEC

The software runs under Windows XP and later. For educational and non-commercial use the software is free without any limitation. See for details the conditions for use.
Click the  button below for a download of the program. The file  must be unzipped in a directory of your choice. 


After start-up of the program the user can create a new mechanism project, that basically has 4 project stages:
1) Create/add elements (links) to build a kinematic structure with 1 - 3 DOF's (Degrees of Freedom). At this stage you can drag the mechanism at any node to view its movability.
2) Set a range for the DOF's to define a "run", specify the amount of steps and get the calculations done.
3) Demonstrate the motion on screen (animation).
4) Create graphs that show the motion behaviour.

The (intermediate) result can be saved as a so-called project file (extension .mec). This file can be loaded again to continue/modify the project.
Samples of prepared project files are available to show the capabilities of the current program version. Of course they can be used to test all kinds of actions.
Project files are text files readable for experts. It is not the intention to edit them with a text editor.

Click here for a download of Runmec61, the tutorial and the examples (1 MB)

Runmec release 6.1 offers advanced options like the use of cam elements and driving the input motion by a function specified in an external file.
To handle such external files easily a software toolbox called "the PION package" is used. To support the user to create a PION  file some utility apps are available. They have been
developed in the past at TU Delft by the former CADOM-group. Interested users can download them, together with a detailed PION manual, via the link below. 

Click here for a download of the utilities and the PION user manual (1 MB)

Content of the utility programs:
 - The app Fedit98_XP.exe to create a periodic spline through 2-120 points and save the result as a PION-file.
 - The app FOBtools_XP.exe to create a (periodic) function as a concatenation of standard functions.
 - The app MTFviewer_XP.exe to display a drawing saved to an external file in text format  (Metafile format .MTF according the CADOM group)

First publication of the program: June 17, 2022 ; updated  November 10, 2022.

Current version 6.1 issued on November 30, 2023 . New :
 - cam elements,
 -  postprocessing of graphs by an embedded picture editor

Remarks about Runmec can be addressed to:

Homepage of the author:

<Return to Startpage>