Stimulation Initiative for European Neural Applications
Esprit Project 9811
Qualification of Shock-Tuning for Automobiles.
Company Background
Comar International B.V. is a small mechatronics company located in the center 
of the Netherlands and operating on the international, highly competetive, 
automotive testequipment market. The company has only limited internal research 
resources.
The problem
Among the many factors that influence the safety of driving on public roads 
is the technical maintenance level of the automobile itself. A regular car 
inspection has therefore become a law-enforced reality. At the inspection site, 
a number of dedicated apparatus is installed, on which a standardardized probing 
of the safety limits is performed. To a lesser degree this also involves the 
safety margins or, in other words, the comfort of driving. The correct tuning 
of shocks has a major impact on the driving characteristics of an automobile. 
However, the shocks take effect in combination with suspension stifness and 
tyre hardness and hence current testmachinery can not reliably distinguish 
between them. As effect it is estimated that at least 30% of the automobiles 
of the public roads still have inferior shocks, which potentially can be the 
cause of accidents. Several attempts have been made in the past to isolate 
the effect of shock-tuning but to no avail.
Neural network application
Measurement data have been taken from a range of vehicles under different maintenance 
conditions on an existing apparatus. After establishing that the information 
content suffices for neural processing, a neural feedforward network has been 
trained by error backpropagation and validated in the InterAct environment 
to approximate the shock characteristics. This prototype function is ensuing 
mathematically optimized for robustness and stability. The final network is 
currently introduced in a new market offering to be sold on an international 
scale.
Benefit
Neural networks allow a real-time correlation of measurement data to prototype 
with various signal processing algorithms. In this manner a cost-effective 
weighting algorithm has been found that adapts easily to different car types 
and operating conditions. The mixed approach with neural rapid prototyping 
and classical mathematical optimization techniques has proven to be very effective 
for modelling non-algorithmic problems.
Generalization
The transition in technology base from mechanical to mechatronical through 
the introduction of microsystems brings more than a simple cost reduction. 
It also brings a sensitive set of data channels carrying influences from a 
large number of sources. Instead of filtering out the signal as desired by 
design, the quest is for a design in which many signals can be viewed in combination. 
In conventional technology, mechanical micromachining has forced diagnosis 
on a one feature per machine basis. Advances in microelectronics allow for 
combined sensory systems in which the careful construction is replaced by novel 
signal processing and optimal adaptivity by in-product training.
Contact Person
Dr.Ir. J.A.G. Nijhuis, Rijksuniversiteit Groningen, Dept. of Computing Science, 
P.O. Box 800, NL-9700 AV Groningen (The Netherlands)