Strain gages on the drive shaft for torque measurement

[tom cloud]

>In regards to the message about placing strain gages on the drive shaft:
>
>Don't just rule out slip rings by saying they are "complicated".  Most
>modern slip rings use brushes on gold contacts, where the contacts 
>are mounted on a spindle of only a quarter inch diameter.  The angular 
>velocity is therefore very low.  Hence, brush noise is minimal.
>		--Daniel Burk

Gad, consider a practical application:  the slop (sic) ring would
have to be mounted to both the rotating, bouncing shaft and the chassis.
Imagine the mechanism required to do that alone.  Plus, you'd have
to figure out how to keep dirt, water, grease, etc out of the
rings, not counting the cost of making them and getting an unbroken
ring pressed onto shaft (else would wear the brush or generate
noise).  Sounds okay for the lab -- not very practical for the
road.

tom cloud