Best Book on PID ??

[John Larkin]

On Thu, 25 Nov 2004 12:28:37 -0500, Phil Hobbs
<pcdhSpamMeSenseless@us.ibm.com> wrote:

I don't disagree that there are lots of similarities, or that there's a lot
of jargon in control system design that seems intended to preserve job
security rather than make concepts clear. (There's a lot of that in some
optics disciplines too--it isn't just an EE problem. Not to mention all of
anthropology.) If I'm designing e.g. a laser temperature controller, I use
Bode plots: one for each of several representative choices of ambient
temperature and thermal forcing. PLL design with nonlinear tuning is
similar. Not everything is that simple, however.

Lots of control systems have to work in situations where an ugly settling
transient will cause destruction--from burned cookies and broken drive belts
to loss of life and property. There are very few purely electronic
situations (i.e. other than driving mechanical devices or large magnets)
where a poor transient response is that serious.

Ordinarily, with an amplifier driving a speaker, say, you can have a few pops
and bangs, but no great harm is done, and they can be tuned out during
debugging. The nonlinearity is of a simple and intuitive sort, and there is
no complex coupling. There is also usually no external forcing, unlike e.g.
a motor controller which may have very different loads at different times.
It isn't possible to test every situation, and it's the ones we haven't
thought about that will turn round and bite us in the backside. Systems that
are uncoupled during normal operation, but become coupled due to faults and
transients, are a common source of this.

It's interesting that a lot of real-world control loops leave theory
way behind, except for the fairly boring region of near-steady-state
operation around null. The hairy parts, the transient and exception
conditions, revert to art, instinct, and maybe simulation.

I like systems like that.

John

 

[Rhett Oracle]

On Thu, 25 Nov 2004 09:45:23 -0800, John Larkin wrote:

On Thu, 25 Nov 2004 12:28:37 -0500, Phil Hobbs
pcdhSpamMeSenseless@us.ibm.com> wrote:

I don't disagree that there are lots of similarities, or that there's a lot
of jargon in control system design that seems intended to preserve job
security rather than make concepts clear. (There's a lot of that in some
optics disciplines too--it isn't just an EE problem. Not to mention all of
anthropology.) If I'm designing e.g. a laser temperature controller, I use
Bode plots: one for each of several representative choices of ambient
temperature and thermal forcing. PLL design with nonlinear tuning is
similar. Not everything is that simple, however.

Lots of control systems have to work in situations where an ugly settling
transient will cause destruction--from burned cookies and broken drive belts
to loss of life and property. There are very few purely electronic
situations (i.e. other than driving mechanical devices or large magnets)
where a poor transient response is that serious.

Ordinarily, with an amplifier driving a speaker, say, you can have a few pops
and bangs, but no great harm is done, and they can be tuned out during
debugging. The nonlinearity is of a simple and intuitive sort, and there is
no complex coupling. There is also usually no external forcing, unlike e.g.
a motor controller which may have very different loads at different times.
It isn't possible to test every situation, and it's the ones we haven't
thought about that will turn round and bite us in the backside. Systems that
are uncoupled during normal operation, but become coupled due to faults and
transients, are a common source of this.


It's interesting that a lot of real-world control loops leave theory
way behind, except for the fairly boring region of near-steady-state
operation around null. The hairy parts, the transient and exception
conditions, revert to art, instinct, and maybe simulation.

Just like life! Imagine that!

I like systems like that.

Me, Too!

John

;^j
R.

 

[Lasse Langwadt Christense]

John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote in message news:<n86cq0h4rh5hmp04av0drra3g0phjq3k1q@4ax.com>...

On Thu, 25 Nov 2004 12:28:37 -0500, Phil Hobbs
pcdhSpamMeSenseless@us.ibm.com> wrote:

I don't disagree that there are lots of similarities, or that there's a lot
of jargon in control system design that seems intended to preserve job
security rather than make concepts clear. (There's a lot of that in some
optics disciplines too--it isn't just an EE problem. Not to mention all of
anthropology.) If I'm designing e.g. a laser temperature controller, I use
Bode plots: one for each of several representative choices of ambient
temperature and thermal forcing. PLL design with nonlinear tuning is
similar. Not everything is that simple, however.

Lots of control systems have to work in situations where an ugly settling
transient will cause destruction--from burned cookies and broken drive belts
to loss of life and property. There are very few purely electronic
situations (i.e. other than driving mechanical devices or large magnets)
where a poor transient response is that serious.

Ordinarily, with an amplifier driving a speaker, say, you can have a few pops
and bangs, but no great harm is done, and they can be tuned out during
debugging. The nonlinearity is of a simple and intuitive sort, and there is
no complex coupling. There is also usually no external forcing, unlike e.g.
a motor controller which may have very different loads at different times.
It isn't possible to test every situation, and it's the ones we haven't
thought about that will turn round and bite us in the backside. Systems that
are uncoupled during normal operation, but become coupled due to faults and
transients, are a common source of this.


It's interesting that a lot of real-world control loops leave theory
way behind, except for the fairly boring region of near-steady-state
operation around null. The hairy parts, the transient and exception
conditions, revert to art, instinct, and maybe simulation.

I like systems like that.

John

see this? http://users.erols.com/jyavins/servo.html

-Lasse