Subject: Control issues on Toyota
Date: Mon, 1 Feb 1999 19:07:21 -0600
From: "Gram, Marty" <Marty.Gram@mts.com>
To: "Hessburg, Thomas" <Thomas.Hessburg@mts.com>, "Kusner, Dave"
     <Dave.Kusner@mts.com>, "Larson, Rod" <Rod.Larson@mts.com>
CC: "Albright, Joe" <Joe.Albright@mts.com>

Joe has been having good success generating wave forms on the sled
during the last 2 weeks.  Some of the control changes that improve the
waveform are:

--  No feedback.  He eliminated feedback from the poppet LVDT and is
running open loop.  The only feedback is from the 256 LVDT,  (It may be
necessary to add poppet feedback at the test start and finish)

--  Poppet control delta p must be reduced to the point where the poppet
starts to leak before starting the test.  When there is a big force
holding the poppet closed at the start, you get big oscillations at
startup.

--  There is some acceleration noise at the end of some of the test
pulses that appear to be caused by uncontrolled poppet movement.  It may
be necessary to add in some poppet feedback to reduce it.

--Marty
