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Groups > sci.physics > #509512 > unrolled thread
| Started by | Sam Wormley <swormley1@gmail.com> |
|---|---|
| First post | 2015-07-25 20:23 -0600 |
| Last post | 2015-08-03 09:34 -0700 |
| Articles | 13 on this page of 93 — 17 participants |
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Sensors in Motion Launches MEMS-Based Inertial Nav System Sam Wormley <swormley1@gmail.com> - 2015-07-25 20:23 -0600
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System kefischer <emoneyjoe@iglou.com> - 2015-07-26 15:40 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System wobbly <wobbly@dont-email.me> - 2015-07-28 22:14 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-07-26 23:20 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Lofty Goat <rlwatkins@gmail.com> - 2015-07-26 23:46 -0500
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Lofty Goat <rlwatkins@gmail.com> - 2015-07-26 23:44 -0500
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-07-27 22:52 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-07-28 16:41 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-01 12:32 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-02 15:51 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-02 20:29 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-03 01:12 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-03 00:07 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-03 12:17 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-08-03 09:36 -0700
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-03 19:00 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Bohuš Matuška <bohu@paranetnet.net> - 2015-08-03 18:01 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-03 20:31 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Bohuš Matuška <bohu@paranetnet.net> - 2015-08-03 19:28 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-03 18:01 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-03 14:52 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-03 23:00 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-06 10:36 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-07 07:58 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-07 08:35 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-07 10:13 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-08 00:26 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-07 22:25 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-08 07:14 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-08 05:44 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Emmerich Schultheiß <emme@noemail.thx> - 2015-08-08 13:23 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-08 10:16 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-08 10:34 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-09 10:47 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-09 17:09 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Emmerich Schultheiß <emme@noemail.thx> - 2015-08-09 17:24 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-09 17:56 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-09 20:05 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-09 18:44 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Emmerich Schultheiß <emme@noemail.thx> - 2015-08-09 19:08 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-10 10:49 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-09 19:53 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-09 18:47 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-09 17:52 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-10 00:07 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-09 22:33 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Felipe Delgado <fd@spreadspectrum.org> - 2015-08-09 22:55 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Felipe Delgado <fd@spreadspectrum.org> - 2015-08-09 22:58 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-10 10:54 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-10 17:38 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Felipe Delgado <fd@spreadspectrum.org> - 2015-08-10 18:07 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-11 01:11 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-10 23:28 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-09 20:43 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-10 10:55 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-10 11:01 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-10 09:32 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-10 17:42 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-11 11:38 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-11 23:00 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-11 22:27 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-11 22:12 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Tom Roberts <tjroberts137@sbcglobal.net> - 2015-08-12 23:32 -0500
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-13 07:32 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 07:30 -0500
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Mahipal <mahipal7638@gmail.com> - 2015-08-13 05:50 -0700
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Felipe Delgado <fd@spreadspectrum.org> - 2015-08-13 13:11 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 08:23 -0500
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Felipe Delgado <fd@spreadspectrum.org> - 2015-08-13 13:28 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-13 15:20 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Felipe Delgado <fd@spreadspectrum.org> - 2015-08-13 13:22 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 07:24 -0500
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-13 15:10 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Felipe Delgado <fd@spreadspectrum.org> - 2015-08-13 13:15 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-13 15:21 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-13 16:26 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 16:35 -0500
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-13 21:52 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Odd Bodkin <bodkinodd@gmail.com> - 2015-08-14 07:42 -0500
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-14 14:04 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System dsr@mail.lns.cornell.edu (Daniel S. Riley) - 2015-08-13 12:27 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-11 22:20 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-09 11:39 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-09 12:42 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-11 14:40 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Poutnik <poutnik4nntp@gmail.com> - 2015-08-11 22:35 +0200
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Jackpol11@hotmail.com - 2015-08-12 21:56 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-03 17:57 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2015-07-30 11:03 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2015-08-04 03:10 -0400
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System jimp@specsol.spam.sux.com - 2015-08-04 17:24 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System wobbly <wobbly@dont-email.me> - 2015-07-28 22:01 +0000
Re: Sensors in Motion Launches MEMS-Based Inertial Nav System "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-08-03 09:34 -0700
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| From | dsr@mail.lns.cornell.edu (Daniel S. Riley) |
|---|---|
| Date | 2015-08-13 12:27 -0400 |
| Message-ID | <shbnebqhkx.fsf@lnxcu9.classe.cornell.edu> |
| In reply to | #512902 |
Jackpol11@hotmail.com writes: > As a result I finally wrote a complicated paper in the Journal of the > Optical Society JOSA October 1967 "Matrix analysis of gimbaled mirror > and prism systems)". (For $45 you can get a copy.) > That is certainly one of the drawbacks of the "peer-reviewed" system. > Essentially nobody gets to see it. Current OSA policy allows posting a preprint of the manuscript to arXiv.org, where anyone with an internet connection can get it. So that at least has improved since 1967. -dan
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| From | Jackpol11@hotmail.com |
|---|---|
| Date | 2015-08-11 22:20 -0400 |
| Message-ID | <p7blsa13b41lb3ujm2rb5dakejn707ibfv@4ax.com> |
| In reply to | #512715 |
On Tue, 11 Aug 2015 11:38:04 -0400, Jackpol11@hotmail.com wrote: >On Mon, 10 Aug 2015 11:01:50 +0200, Poutnik <Poutnik4NNTP@gmail.com> >wrote: > >>On 08/10/2015 02:43 AM, Jackpol11@hotmail.com wrote: >>>> >>>> Why do you think trigonometric functions >>>> are not involved in analogue systems ? >>>> They are, and even better than in digital ones, >>>> as they are analogue continuous functions. >>>> >> >>> I think my work here is done. >>> John Polasek >> >>I hope not. >> >>Do not get me wrong, John ( you would be Jan Polášek here ). >> >>I fully respect your big experience with gyroscope systems. >> >>I just wanted to point out that not all >>is like them today, in both high and low ends..... >That reminds me of the time (1972?) I was hired by a company to >digitize their analog aircraft something simulator. There was a very >large schematic with op-amp integrators (they may have used homemade >op-amps). There were about a half-dozen resolvers and the guy >explained to me they didn't know what to do with them. >So I figured out the proper matrix equations for each resolver that >could then be used in the digital version. >But, notice, the thing was working before I wrote any equations. Just >put a resolver wherever there's an axle that turns and the job is >done. >The originating resolver forms a magnetic vector V, from the inputs X >and Y (like you would do with a straight edge on paper) and that same >magnetic V is properly dissected by the secondary coils into the 2 >true geometric components in the next coordinates set offset by that >angle. >(redundancy noted) >John Polasek >AKA chopper stabilizers, to eliminate drift. These inertial guidance systems I worked on, all of the signals were 400 cycle AC which had to be rectified before integrating, then possibly re-modulated for further use. The synchros and resolvers required 400 cps. With this frequency less iron was required in the transformers, but higher frequencies would be bothered by the capacitance of the coils, approaching self resonance. These inertial guidancesystems went into ICBMs that stood vertically with the inertial platform on top. To align the platform into the plane of the target, a theodolite beam was sent up to a Porro prism and adjustments were made. This prism is sensitive only on one axis. I was given the task ofcalculating the azimuth errors resulting from tilts on the pitch and roll axes (which were supposedly neutralized out). As a result I finally wrote a complicated paper in the Journal of the Optical Society JOSA October 1967 "Matrix analysis of gimbaled mirror and prism systems)". (For $45 you can get a copy.) That is certainly one of the drawbacks of the "peer-reviewed" system. Essentially nobody gets to see it. John Polasek
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| From | Poutnik <poutnik4nntp@gmail.com> |
|---|---|
| Date | 2015-08-09 11:39 +0200 |
| Message-ID | <mq770l$k51$1@dont-email.me> |
| In reply to | #511885 |
Dne 08/08/2015 v 16:34 Jackpol11@hotmail.com napsal(a): > (Taki osel!) People calling others fools and donkeys are seldom wise. -- Poutnik ( the Czech word for a wanderer )
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| From | Poutnik <poutnik4nntp@gmail.com> |
|---|---|
| Date | 2015-08-09 12:42 +0200 |
| Message-ID | <mq7ao2$38t$1@dont-email.me> |
| In reply to | #511885 |
Dne 08/08/2015 v 16:34 Jackpol11@hotmail.com napsal(a): > (Taki osel!) Osel would publish on Wikipedia without giving the reference. -- Poutnik ( the Czech word for a wanderer )
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| From | Jackpol11@hotmail.com |
|---|---|
| Date | 2015-08-11 14:40 -0400 |
| Message-ID | <n9gksalfa6ms346cr52ftc65tq9ia470l1@4ax.com> |
| In reply to | #511569 |
On Thu, 06 Aug 2015 10:36:05 -0400, Jackpol11@hotmail.com wrote: >On Mon, 3 Aug 2015 23:00:17 +0200, Poutnik <poutnik4nntp@gmail.com> >wrote: > >>Dne 03/08/2015 v 20:52 Jackpol11@hotmail.com napsal(a): >>>> >>>> In fact, "untrue" gyroscopes are more true gyroscopes than "true" >>>> gyroscopes. "True" gyroscopes are not not well suited >>>> for "watching the circle", >>>> they just try to keep the platform free from any rotation. >>>> >>>> There are 2 possible approaches for inertial systems, wrt rotation: >>>> 1/ to keep the orientation >>>> 2/ to know how orientation changed >>>> >>>> In fact, systems based on MEMS are reaching quality of classical >>>> gyroscopes, with advantage of price, mass, volums and durability. >> >>> You are imagining what is called a "strapped-down" inertial system. I >>> believe that calls for Euler's equations which cannot be solved in >>> closed form. This vehicle will be assuming all kinds of different >>> orientations and it would be sheer folly to think that you could >>> subtract gravity out of the real accelerations. >> >> >>"Strapdown systems are nowadays commonly used in commercial and tactical >>applications (aircraft, ships, ROV's missiles, etc.) and are starting to >>become more widespread in applications where superb accuracy is required >>(like submarine navigation or strategic ICBM guidance) and FOG based >>strapdown inertial navigation systems have been selected by the UK Royal >>Navy for the Astute class submarine and the Queen Elizabeth class >>aircraft carriers." >> >>https://en.wikipedia.org/wiki/Inertial_navigation_system#Strapdown_systems >> >>> The inertial platform is actually set in a roll gimbal inside a pitch >>> gimbal inside a yaw gimbal fully retaining its inertial position >>> throughout while the gimbal angles change as aircraft maneuvers. The >>> gyroscope error signals are sent through resolvers that perform >>> matrix transformations, apportioning the torques to the correct >>> gimbals. >> >>I am aware of that. >>But truth is, not limited to gyroscopes and navigation systems, >>people experienced in past technology >>often ignore advances of incoming technologies. >>What was true 2 years ago need not to be true now. >> >>> The general idea as I said in the 1st place is preserve and protect >>> the accelerometers so they measure only navigational accelerations. >>> The error signals from the gyroscope provide the rigidity required to >>> resist torques from the gimbal angles as they change. >>> I also mentioned that the accuracy needs to be at least .01° per hour >>> which translates to 0.000002778° per second and the resolution of the >>> mems might be 0.03, and therefore nowhere qualified for navigation >>> purposes. >> >>Peiple saying it is not possible >>should not interupt those doing it. ( chinese proverb ) >> >>All depends on purpose of the navigation. >>For some applications 0.01 deg / hour is far from needed. >> >>To have the platform leveled is equivalent >>to knowledge how it is tilted. >> >> >>> Ti si hloupak! >> >>Correct form would be "Ty jsi hlupák !" >>But such a calling would say more about its author...him > >Enough of the fun! They may or may not be using strapped down systems, >which are fraught with hazards. I'm referring to the gimbaled systems >discussion. >For that I looked up >https://en.wikipedia.org/wiki/Gimbal#Inertial_navigation >which fills in more detail about the function of gimbals. The article >has a number of errors, since it is apparently written by someone with >no actual knowledge because he says that gimbal angles are measured to >provide the 9 direction cosines needed for navigation. instead, the 3 >resolvers (transformers) automatically parcel out all the gyro >signals to the proper axes. >Therefore I edited it, which was apparently effective immediately. >(See inertial navigation section). > >John Polasek I notice this thread is more complete in science physics. This is poor practice.
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| From | Poutnik <poutnik4nntp@gmail.com> |
|---|---|
| Date | 2015-08-11 22:35 +0200 |
| Message-ID | <mqdm78$31q$1@dont-email.me> |
| In reply to | #512773 |
Dne 11/08/2015 v 20:40 Jackpol11@hotmail.com napsal(a): > On Thu, 06 Aug 2015 10:36:05 -0400, Jackpol11@hotmail.com wrote: > > I notice this thread is more complete in science physics. This is poor > practice. > Strange. Speaking for myself, I did not cat away sci.physics. -- Poutnik ( the Czech word for a wanderer )
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| From | Jackpol11@hotmail.com |
|---|---|
| Date | 2015-08-12 21:56 -0400 |
| Message-ID | <ettnsadr8vaqlpjvprlb35a4gtq15kn08q@4ax.com> |
| In reply to | #512833 |
On Tue, 11 Aug 2015 22:35:23 +0200, Poutnik <poutnik4nntp@gmail.com> wrote: >Dne 11/08/2015 v 20:40 Jackpol11@hotmail.com napsal(a): >> On Thu, 06 Aug 2015 10:36:05 -0400, Jackpol11@hotmail.com wrote: >> >> I notice this thread is more complete in science physics. This is poor >> practice. >> >Strange. >Speaking for myself, I did not cat away sci.physics. I should mention something about the details of this early computing. All of the signals were 400 cycle AC which had to be rectified before integrating, then possibly re-modulated for further use. The synchros and resolvers required 400 cps. With this frequency less iron was required in the transformers, but higher frequencies would be bothered by the capacitance of the coils, approaching self resonance. These systems went into ICBMs that stood vertically with the inertial platform on top. To aim it, you align the platform into the plane of the target, where a theodolite beam was sent up to a Porro prism and Azimuth adjustments were made. This prism is sensitive only on one axis. I was given the task of calculating the yaw errors resulting from tilts on the pitch and roll axes (which were supposedly neutralized out by the prism). As a result I finally wrote a complicated paper in the Journal of the Optical Society JOSA October 1967 "Matrix analysis of gimbaled mirror and prism systems)". (For $45 you, or I, can get a copy.) That is certainly one of the drawbacks of the "peer-reviewed" system. Essentially nobody gets to see it. John Polasek
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| From | jimp@specsol.spam.sux.com |
|---|---|
| Date | 2015-08-03 17:57 +0000 |
| Message-ID | <vkm49c-fgj.ln1@mail.specsol.com> |
| In reply to | #510968 |
In sci.physics Jackpol11@hotmail.com wrote: > On Mon, 3 Aug 2015 00:07:56 -0000, jimp@specsol.spam.sux.com wrote: > >>In sci.physics Poutnik <poutnik4nntp@gmail.com> wrote: >>> Dne 02/08/2015 v 21:51 Jackpol11@hotmail.com napsal(a): >>>> On Sat, 1 Aug 2015 12:32:41 +0200, Poutnik <poutnik4nntp@gmail.com> >>>> wrote: >>>> >>>>> Dne 31/07/2015 v 22:58 Jackpol11@hotmail.com napsal(a): >>>>> >>>>>> I didn't hear you say anything helpful, sure they are a different kind >>>>>> of gyroscope that hopefully can compete in accuracy with the >>>>>> conventional ones. If their function is not to keep a local vertical, >>>>>> and keep gravity out of the accelerometers,then what is it? >>>>> >>>>> Classical meaning of gyroscope >>>>> as measure against to be rotated >>>>> misses the etymology of the word. >>>>> >>>>> Freely translated it is "noticing the rotation", >>>>> and this is followed by MEMS gyroscopes . >>>>> >>>>> https://www.google.cz/search?q=MEMS+gyroscope >>>>> >>>>> http://www.quora.com/How-does-a-MEMS-gyroscope-work >>>>> >>>>> https://en.wikipedia.org/wiki/Vibrating_structure_gyroscope >>>>> >>>>> https://www.youtube.com/watch?v=A03AENwOVNY >>>>> ( MEMS gyroscopes - A revolutionary way to interface with the real world >>>>> (ePresentation) ) >>>>> >>>>> http://electroiq.com/blog/2010/11/introduction-to-mems-gyroscopes/ >>>> I've read one of the articles by the manufacturer, and I see these >>>> gyroscopes are nothing more than rate gyroscopes which are not really >>>> gyroscopes, but sensors of angular rate. They are of great use in >>> >>> Greek gyros "a circle" (see gyre (n.)) + skopos "watcher" (see scope >>> (n.1)), because the device demonstrates that the earth rotates. >>> >>> Gyroscope IS a sensor of angular rate. >> >>A gyroscope CAN BE a sensor of angular rate, and several other things >>including just a toy. > A rate gyroscope is elastically restrained with a spring. > A true gyroscope as used in an inertial guidance system is insulated > against the angular rates by virtue of being mounted in gimbals, from > which the angles can be read for navigation computation. It tries to > maintain a rigid orientation in an inertial space. Deviation sensed by > gyroscopes produce correction torques at the gimbals. > John Polasek The word "gyroscope" is generic and implies nothing more than a spinning wheel with freedom of rotation in all three axes. It is only after you add qualifiers that it has any particular characteristic such sensing angular rate, e.g. a rate gyroscope. What does this gyroscope sense? http://www.arborsci.com/original-gyroscope?gclid=CjwKEAjwovytBRCdxtyKqfL5nUISJACaugG13eQG-9_7h_Rj2s-uS6FCF-qptjrCEI6hSCrZn6aZ0hoCFNrw_wcB -- Jim Pennino
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| From | Yousuf Khan <bbbl67@spammenot.yahoo.com> |
|---|---|
| Date | 2015-07-30 11:03 -0400 |
| Message-ID | <DcadndBV2e4yoSfInZ2dnUU7-Yli4p2d@giganews.com> |
| In reply to | #509938 |
On 29/07/2015 7:58 PM, jimp@specsol.spam.sux.com wrote: > If you need GPS to drive through a tunnel, then I pity everyone else > on the road with you. > > You sound like one of those people who follow their GPS and drive off > the end of a pier when the ferry boat isn't there. You've never driven in Montreal have you? Yousuf Khan
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| From | Yousuf Khan <bbbl67@spammenot.yahoo.com> |
|---|---|
| Date | 2015-08-04 03:10 -0400 |
| Message-ID | <_-KdnVT9_MvT-F3InZ2dnUU7-eudnZ2d@giganews.com> |
| In reply to | #510338 |
On 30/07/2015 2:10 PM, jimp@specsol.spam.sux.com wrote: > It is irrelevant whether or not I have driven in any particular place. > > Do they not have paved roads and road signs in Montreal? As I said, you've never driven in Montreal. The roads are paved in potholes, and the signs are all in French. And lights in tunnels are hit and miss. Not hard to miss your off-ramp in a dark tunnel while your eyes are being jostled out of their sockets, meanwhile you're trying to translate the French into English in your mind. > Saying someone needs GPS to drive through a tunnel or a parking garage > is just plain silly. It is in place where you've been, but not in places where you've never been before. Your own little perspective on life is of very little relevance to the real world. Yousuf Khan
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| From | jimp@specsol.spam.sux.com |
|---|---|
| Date | 2015-08-04 17:24 +0000 |
| Message-ID | <r2979c-tes.ln1@mail.specsol.com> |
| In reply to | #511121 |
In sci.physics Yousuf Khan <bbbl67@spammenot.yahoo.com> wrote: > On 30/07/2015 2:10 PM, jimp@specsol.spam.sux.com wrote: >> It is irrelevant whether or not I have driven in any particular place. >> >> Do they not have paved roads and road signs in Montreal? > > As I said, you've never driven in Montreal. The roads are paved in > potholes, and the signs are all in French. And lights in tunnels are hit > and miss. Not hard to miss your off-ramp in a dark tunnel while your > eyes are being jostled out of their sockets, meanwhile you're trying to > translate the French into English in your mind. Oh boo hoo. Try driving somewhere where the roads are mostly unpaved and the few signs there are are in Korean. >> Saying someone needs GPS to drive through a tunnel or a parking garage >> is just plain silly. > > It is in place where you've been, but not in places where you've never > been before. Your own little perspective on life is of very little > relevance to the real world. Any five year old can find the end of a tunnel. Once you exit the tunnel, it only takes a few seconds for GPS to relock unless you spent several hours inside the tunnel. -- Jim Pennino
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| From | wobbly <wobbly@dont-email.me> |
|---|---|
| Date | 2015-07-28 22:01 +0000 |
| Message-ID | <mp8u4d$bm$1@speranza.aioe.org> |
| In reply to | #509792 |
Lofty Goat wrote: > On Sun, 26 Jul 2015 13:33:20 +0000, Fritz Köhler wrote: > >> jimp wrote: >> >>> Sam Wormley <swormley1@gmail.com> wrote: >>>> Sensors in Motion Launches MEMS-Based Inertial Nav System >>> >>> It still needs calibration by something like GPS shit head. >> >> MEMS does not need GPS calibration, asshat. That's the whole idea with >> inertial MEMS, they calibrate by completely other means. What an idiot, >> lol, to calibrate MEMS by GPS. > > Given your great willingness to speak up, I wish you knew what you were > talking about. Pennino may blather some, but at least he knows things: > "MEMS" doesn't necessarily "require calibration" or "not require > calibration". It's an acronym for micro-electro-mechanical-system. > MEMS-based *inertial guidance systems* do require calibration. They > drift. Some of them drift less than others, but they all drift. You must be at least as stupid jimp is. The magnetic sensor and the accelerometer are not drifting. Those needs calibration before use in whatever orientation/navigation application. The main source of (signal) drift comes from the gyros used. Those are prone to drift indeed.
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| From | "reber g=emc^2" <herbertglazier0@gmail.com> |
|---|---|
| Date | 2015-08-03 09:34 -0700 |
| Message-ID | <0efdf6d7-b502-4ff6-a0dc-18a5284a3f70@googlegroups.com> |
| In reply to | #509512 |
On Saturday, July 25, 2015 at 7:23:41 PM UTC-7, Sam Wormley wrote: > Sensors in Motion Launches MEMS-Based Inertial Nav System > > http://gpsworld.com/sensors-in-motion-launches-mems-based-inertial-nav-system/ > > > Sensors in Motion (SIM) has introduced a MEMS > > (micro-electro-mechanical) navigation-grade inertial system (INS) > > that it says could transform the $8 billion/year inertial market with > > new products by offering price and performance specifications better > > than those currently available. > > > > The first INS devices have been delivered to the Army CERDEC Night > > Vision Electronic Sensors Directorate (NVESD). > > > > SIM, a spinout from NASA's Jet Propulsion Laboratory and California > > Institute of Technology, is developing a family of high-accuracy MEMS > > gyroscopes, accelerometers and inertial measurement unit ( IMU) > > solutions. It says it has perfected unique MEMS structures using > > volume silicon wafer processing techniques to produce gyroscopes > > having ARW (angle random walk) less than 0.0035 degree/root-hour and > > bias instability less than 0.01 degree/hour with extraordinary > > vibration and temperature immunity, a performance comparable to ring > > laser (RLG) and fiber optic (FOG) gyros that are 20 times larger and > > 100 times more expensive. > > > > These features are mandatory for numerous applications where location > > is not available from GPS or vehicle position accuracy is required > > including autonomous vehicles, drones, mining asset tracking, dead > > reckoning, agricultural seed placement, oil and gas directional > > drilling, self-driving autos, firefighter navigation, optical image > > stabilization, industrial equipment azimuth, aerospace and defense > > products and most GPS-denied environments, in addition to new > > applications. > > -- > > sci.physics is an unmoderated newsgroup dedicated > to the discussion of physics, news from the physics > community, and physics-related social issues. My 70 year old gyro gave me three theories Spin is in. Wabble theory.Structure of electron theory. How coupling twins work.Idea on features of spinning at close to c on BHs features .I just pulled the string and at fast spin gyro has no wobble.It resist falling on its side,and will push back.It is set with Earth's pull of gravity,and the gravity of all there is.To me it was the greatest birthday present in the world. Bert
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