Thanks Chris,

Surely there are new high tech sensors we amateures
may not be aware of that possibly we may obtain.
It seems there has been no advancements in the sensor area.
I had great troubles with the piezo idea because
it has such a high impedence. Whatever i do I must use
a balanced preamp system with most of the gain
in the front end or the drifting of the class "A" baseline is unacceptable.
Isnt there a varible resistor that might work over a range of
a few mm for full scale ?? The key is most probably the
range of operation and these special kind of devices
are just not normally made available to the general public.
At the moment only a magnet coil seems to fill the billit
since I am unwilling to use home built AC devices like capacitive (moving plates) or
inductive (moving cores)  sensors. If I had an fcc license I might try
those AC devices but since i do not i will not.
Right now only baseband and DC are my options.
Low impedance front ends have always been best for me.

Is there any way for the layman to realistically research the new sensors that might be out there ?

Regards;
geoff


----- Original Message ----- 
From: 
To: 
Sent: Wednesday, June 27, 2007 16:05
Subject: Re: Multi-Dimensional-Sensor, First Time Of Arrival Only


> In a message dated 2007/06/27, gmvoeth@........... writes:
> 
>> I was just wondering if you connected a strain guage or
>> other sensor type unknown to me where the vertical pendumlum
>> wire joins at the upper support if you could possibly
>> measure weight changes that might result from motion in any
>> of the three axises ?
> 
> Hi Geoff,
> 
>       You are unlikely to have much success with Strain Gauges. The likely 
> problems are with sensitivity and noise. They tend to have quite a low 
> sensitivity. It might be interesting to try suspending a pendulum using 1/2 a piezo 
> disk? 
> 
>       Regards,
> 
>       Chris Chapman   
>
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