ATTN: Bob O - Weight Control via PID?

I did some searching on the site before posting this, and came across Bob O's thread from a year ago:

http://www.plctalk.net/qanda/showthread.php?s=&threadid=4385&highlight=PID+weight+control

My application is almost identical, but rather than change machine speed, I will be changing the revolutions of a servo running a volumetric filler. I have the same setup; fill container-->move to next position-->checkweigh and calculate adjustment-->send to servo for next container.

I had originally thought about PID control for this process until I searched and found Bob's thread and was wondering if he could post his success/failure with Bernie Carlton's suggestion, as it seemed to be the accepted solution. I tried the same approach(Bernie's) once in the past on a different application with limited success, so I had to wonder if anyone had attempted this with PID control.

Also, in a year's time, the forum has many new members who may have a different approach to this. I'm all ears!

Thanks,
Jeff

Jeff,

It works like I expected. I will try to explain more of what I did later today sometime.

Thanks,
Bob O.

Edit- I didn't use PID.