The continuous improvement process (CIP) is a well established
method for short-time improvements of manufacturing systems and processes.
The central idea of the CIP is to take direct advantage of the worker’s expertise
by integrating them into the improvement process. On a regular basis,
a CIP workshop is arranged where workers can report on bottlenecks in the
production and solutions are elaborated.
Many activities of a workshop, such as analysing current manufacturing processes
or identifying improvement potentials, are performed within the physical
working environment. This impairs the ongoing production process and may
cause unwanted production downtime. A promising approach is to decouple
the elaboration and evaluation of improvement measures from the ongoing production
using the Virtual Reality-technology (VR). This way, flaws can be
avoided and multiple variants can be compared before the expensive process of
implementing changes on the production line is started.
We presume that we have a detailed model of the hall and the
assembled product in Virtual Reality Modeling Language (VRML). In a first
step we reorganize this data in order to make it fit for the virtual CIP. The
reorganization includes an instanciation of similar objects and the creation of
a masterfile in a new XML-based format. If necessary we can simplify the meshes
with a method based on QSlim in order to increase performance.
Then we load the refined data into the KoVir Frontend. This is a powerful
tool in which we can easily reproduce the existing assembly line, through the
use of a novel product assembly graph. This graph contains (but is not limited
to) the following information:
assembly hierarchy for all parts of the product
geometric information where these parts are stored and assembled
transportation information concerning the assembly paths
links to additional information, like rigid body simulations.
Then we start optimizing the assembly line by trying out changes in the layout
of the hall and the assembly process. We visualize the improvements by playing
animations or physical simulations on a laptop or a personal computer in a first
step. If we feel that there are still improvements that can be done, we restart
with optimizing the hall and the process. If we are satisfied with the results
on the desktop computer, we export the assembly line to a Virtual Reality
environment for further evaluation.
In this step we can integrate the workers
directly in the virtual assembly process and test the solutions. If the workers still
report bottlenecks we can go back to the optimization step and apply the changes
suggested by them. The elaboration of solutions on the desktop computer and
the transfer to the Virtual Reality environment work very fast, so that there are
no big waiting times and several approaches can be tested in one CIP-workshop.
Finally when we are satisfied with all simulations on the personal computer
and in the VR environments we can implement the changes into the real world
I am no longer working on this project. You may download the
and the master thesis
on this site. My work may be continued by the
University of Kaiserslautern
John Deere Werke
. Please contact them for further information.