From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,fb1663c3ca80b502 X-Google-Attributes: gid103376,public X-Google-Thread: fac41,e01bd86884246855 X-Google-Attributes: gidfac41,public From: "Marin D. Condic" Subject: Re: Interresting thread in comp.lang.eiffel Date: 2000/07/14 Message-ID: <396F13B6.9216FFE4@acm.com>#1/1 X-Deja-AN: 646311582 Content-Transfer-Encoding: 7bit References: <8ipvnj$inc$1@wanadoo.fr> <8j67p8$afd$1@nnrp1.deja.com> <395886DA.CCE008D2@deepthought.com.au> <3958B07B.18A5BB8C@acm.com> <395A0ECA.940560D1@acm.com> <8jd4bb$na7$1@toralf.uib.no> <8jfabb$1d8$1@nnrp1.deja.com> <8jhq0m$30u5$1@toralf.uib.no> <8jt4j7$19hpk$1@ID-9852.news.cis.dfn.de> <3963CDDE.3E8FB644@earthlink.net> <8k5alv$1oogm$1@ID-9852.news.cis.dfn.de> <8kl25k$2q7k0$1@ID-9852.news.cis.dfn.de> Organization: Quadrus Corporation X-Sender: "Marin D. Condic" (Unverified) X-Server-Date: 14 Jul 2000 13:21:02 GMT Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 Newsgroups: comp.lang.ada,comp.lang.eiffel Date: 2000-07-14T13:21:02+00:00 List-Id: Ken Garlington wrote: > is: Suppose you're driving your car in rush-hour traffic, and someone > suddenly throws black paint on the windshield, and all the windows. Putting > aside such obvious fixes as breaking or rolling down a window (in other > words, using an alternate sensor), what do you do? You could jam on the > brakes (which a rocket or airplane can't do, unfortunately), or you could > take your last known information and try to guess how to turn the wheel so > that you get to the shoulder safely (what I usually call standby gains). I > don't know how successful that is with a rocket; it works OK with an > airplane, but it's a much more benign environment. A common FDA strategy for such a situation would be to go fail-fixed. You hold everything exactly where it is at with the hope that the sensors will come back on-line before disaster happens. If you're in the middle of a burn, you keep burning. In the middle of a coast - keep coasting. If you're in the middle of a transient - you're screwed! With rockets, the strategy is quite often to do your very best to continue to press on with the mission as best you can, because everything else is a total loss. There's no such thing as having the pilot limp the vehicle on back to the base and let the maintenance guys take a look at it. MDC -- ====================================================================== Marin David Condic - Quadrus Corporation - http://www.quadruscorp.com/ Send Replies To: m c o n d i c @ q u a d r u s c o r p . c o m Visit my web site at: http://www.mcondic.com/ "Some people think programming Windows is like nailing jello to the ceiling... easy with the right kind of nails." -- Ivor Horton - Beginning Visual C++ 6 ======================================================================