Miata Mailing List: September 1997, Message #248
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From: 	"Will Brown" <wbrown@comet.net>

Subject: Re: NMC: Hysteresis defined & LIDAR followup

Date: 	Tue, 2 Sep 1997 13:00:12 +0000



> I don't know about mathematically, but they are two entirely different 

> things.



My apologies - I stand corrected - I was confusing Pulse (or 

Pulse/Doppler) RADAR in my head with just pure Doppler RADAR.  I used 

to work with pulsed RADAR systems at my last job - had that stuck in 

the brain.  Pulse RADAR is what's like LIDAR (with the RPF's and all 

that jazz)



> In a mechanical system, hysteresis is just exactly what you

> described. The lag between "input" and "output" ... 



I would still tend to call that the 'hysteresis dead band' rather 

than lag - because if you move that input shaft 'just a little' (not 

enough to get out of the hysteresis dead band) and then *stop* moving 

it, the output shaft will never change direction.  If it was lag, the 

output shaft would move after a little while.  Matter of fact, if you 

get a sloppy enough gearbox, you can diddle the input shaft back and 

forth all day long (within the hysteresis dead band) and never see 

the output shaft move.  If it was just lag, the output shaft would be 

diddling around too... after a while.



\/\/



Team "not an ME or rocket scientist, but I knows hysteresis when I 

sees it"

Team "spirited debate, not an argument"