1994 1995 1996 1997 1998 1999 <2000> 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 | Index | 1994 1995 1996 1997 1998 1999 <2000> 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
<== Date ==> | <== Thread ==> |
---|
Subject: | PID Record |
From: | "Leonard J. Reder" <[email protected]> |
To: | EPICS Tech-Talk <[email protected]> |
Cc: | Mark Colavita <[email protected]>, Sam Crawford <[email protected]> |
Date: | Thu, 01 Jun 2000 12:01:42 -0700 |
Hello: I am utilizing the PID record within EPICS to perform closed loop position control of some mirrors for our interferometer and some questions came up. The PID record's servo loop is now functioning but not as expected. Our application uses PZT like devices to position a Newport Mirror mount and capacitive sensors to read back the position into the CVL input of the PID record. The STPL input accepts the target position for the mirror. The PID record is feeding a AO record. The AO is in incremental mode. For this system integral gain term is all we expect would be needed but the servo does not respond at all until some proportional gain term is added independent of the value of the integral term. Basically the integral term seems to be ignored are we missing something? One other problem I am seeing is that the medm/dm2k GUI does not seem to be picking up the HOPR and LOPR field from the PID record. Is this a known bug. How do I monitor on a GUI the ERR and DM fields? We are using EPICS Release 3.13.0.beta12. Any replies will be greatly appreciated. Len P.S. Thanks to Thomas Birke at Bessy and Kevin Tsubota at Keck for assistance in building the new dm2k application. -- ____________________________________________________ Leonard J. Reder Jet Propulsion Laboratory Interferometry Systems and Technology Section 383 Email: [email protected] Phone (Voice): 818-354-3639 ____________________________________________________