VDI Guidelines - Support material Version March 2020
VDI (= Verein
Deutscher Ingenieure) is the Association of German Engineers. It publishes many
guidelines, written by honorary expert groups, to promote technology
development in science and engineering
businesses. Originally just in German language, nowadays also in English.
of the Guidelines can be bought from the publisher or, for the academic
community, can be viewed in licensed university libraries.
Here is an
example of such a guideline in the field of Mechanisms: The design of a planar
four-bar linkage with the best possible transfer quality (Guideline VDI 2123).
For those who
are familiar with the type of design problem, the support material that the
expert group has made may be beneficial: Excel sheets that contain the
calculations as described in the (intended) new version of the guideline VDI
2123. These Excel sheets are free for a download.
Scope of the guideline VDI
The two pictures
above describe the two main solution types of the design problem: a four-bar
mechanism in which the driving link a and the output link c move either
in equal direction (left picture) or in contrary direction (right picture). The
links a and c will move between a start position and an end
position regarding their angles with the frame. This motion must be contiguous:
intermediate return of the output link is not allowed.
assumes that the rotation angle jH of
the driving link and the rotation angle yH of the output link are given. In
addition a so-called dead point, in one or both end-positions of the driving
link, may be required. The problem to solve is: determine the link dimensions
for maximum quality of motion transfer. This quality is indicated by the
transmission angle μ: its smallest value – in the figures this is
angle μ3 - should be as high as possible. For all cases the highest achievable transfer
quality can be viewed in diagrams and, switching to the right sheet, the link
dimensions can be determined easily. In some cases it is required to read off
design parameters from a diagram.
appropriate link below to obtain the Excel sheets supporting VDI 2123:
Download the English version, filename:
VDI-Guideline2123(E).zip (1.8 kB)
Download the German version, filename:
VDI-Guideline2123(D).zip (1.8 kB)
Remarks can be sent to: email@example.com