Monitoring vibration

Ian McClure <ian.mcclure [at] yale__edu> writes

>I am currently researching vibration monitoring equipment to monitor
>a three-year period of construction at Yale Art Gallery. I would
>like to install a series of vibration monitors, which could be moved
>as needed and placed on walls, floors and in showcases etc. Readings
>would be transmitted to a central logger. The logger would have a
>preset limit for vibration, which after a short period of sustained
>vibration above the set level (to avoid one-off spikes), would send
>out alerts to those overseeing the construction project. This would
>provide real-time monitoring of the project as well as recording
>data for future evaluation.  So far I have not been able to identify
>a company that would provide such a system. Small Tinytag vibration
>monitors are made by Gemini Data Loggers but they do not send data
>to a remote sensor. Gemini data loggers make a data logger that will
>send out alert messages but it is not compatible with the Tinytag
>vibration monitors. I would be grateful to learn if anyone has a
solution to this problem.

If you Google with, for example, remote sensor vibration monitor,
you will find a number of companies providing equipment for remote
sensing. Most of the systems which I am aware of are connected by
wires to a main computer (PC or laptop). You could ask an
engineering company to put a system together. This could consist of
inexpensive accelerometers which would also be connected by cable to
some central data acquisition system. Bruel and Kjaer
<URL:http://www.bksv.com> produces top-of-the-line vibration
monitoring equipment. That might not be necessary, but a visit to
that website might give you some ideas.

I would be curious as to what level will be used as the "set level".
The amount of acceptable vibrations depends on the type and
condition of the object. The effect of vibrations is cumulative.
There is no data in the literature which tells us what vibrations we
can ignore. On the other hand, if the vibrations go above a set
level once in a half year, that might also not be dangerous.

It would be interesting to select specific objects and do regular
condition reports while monitoring vibrations. You could then relate
any changes in condition to vibration activity over a given period
of time (assuming other conditions like climate, etc. remain
constant during that time). That would give museums more information
as to how much vibration objects are allowed to experience.

Dr. W. (Bill) Wei
Afdeling Onderzoek / Research Department
Instituut Collectie Nederland
Netherlands Institute for Cultural Heritage
Postbus 76709
NL-1070 KA Amsterdam
The Netherlands
+31 20 305 47 41
Fax: +31 20 305 47 00


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                  Conservation DistList Instance 22:21
                 Distributed: Sunday, October 12, 2008
                       Message Id: cdl-22-21-005
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