Strain gages on the drive shaft for torque measurement

[Darrell Norquay]

At 12:38 PM 8/26/96 EST, Will McGonegal wrote:

>At out facility we have several torque measuring devices.  To get the 
>excitation voltage to the rotating strain gage and the signal back to 
>the signal conditioner, a non-contact rotary transformer is used.  One 
>set of coils rotates near a stationary set.  Excitation voltage is fed 
>through one set of coils and the signal voltage is fed back through 
>another set.  The excitation voltage is an AC signal (3kHz).  The 
>signal coming back to the signal conditioner is also AC with an 
>amplitude proportional to the torque.
>
>There are a few chassis dynamometers at our lab that have in-line 
>torque transducers that use this type of set up to measure torque.  
>The transducer is mounted between the dynamometer power absorption 
>unit and the rest of the dynamometer.  There is also a car, here, 
>equipped with "torque wheels" that uses rotary transformers to get the 
>signals to and from the strain gages.  Instead of having the strain 
>gage on the drive shaft, this car has an adapter plate that bolts 
>between the hub and the tire (one for each of the drive wheels).  The 
>plates have the appropriate strain gages so that torque can be 
>measured.


Gee Whiz Will, can we come over and play at your place?  ;)

regards
dn
dnorquay at awinc.com