SIDF - A call to any engineers

[Keeripes!]

A shot in the dark... but

If you have taken advanced controls classes, and know what this is I could use some help. Not often do I get snagged on something, but this thing has got me all turned around.

If you know anything about Sinusoidal Input Describing Functions, and how the fuck they fucking work, please help a brother out.

Essentially we introduced backlash into a position controller, and for a report were asked to find the predicted theoretical amplitude and frequency of the limit cycle.

Unfortunately, once I derive the transfer function for the system, sub s=jw, and equate G(jw) = -1/N(A,w) I stare at the page for a half hour stumped as to what to do next. I must have missed that day or something because I have no idea what is going on. Note, for this problem I do have a complex numerical value for the DF.

Also, any material I have found on this is pages and pages and pages of derivations. Sweet fuck, my prof has never done anything like that in class, so it has to be easy, I just can't see it.

Anyways, hopefully one of you guys knows what I am talking about.

Peace,

Kerpez

 

[DarkSiege]

I'm going to pass this on to the inevitable crickets...

 

[BIOP]

damn, you guys actually do shit up at lakehead? I integrated once throughout my whole engineering degree.

 

[HooB.wg]

speak english

 

[Narf!]

Oh man, control systems was like...7 years ago for me. OH DAMN HOW TIME FLIES! Sorry bud, the hamster running the math wheel is old and slow now

 

[Pyro]

Alright, you'll need an ounce of raisins, three ravens' eyes, one strand of unicorn hair, some firewood, matches, and a cauldron filled with water. Heat to a boil, place contents into cauldron, stir for exactly three minutes and twelve seconds, dip a sheet with the problem written on it into the cauldron and quickly retract it.
Now... tell me what you see.

 

[Narf!]

He's not going to see anything. You left out the warm goat blood.

 

[Pyro]

[quote1270649287=Narf!]
He's not going to see anything. You left out the warm goat blood.
[/quote1270649287]
please, leave this to the professionals narf.

 

[Shotgun Jesus]

What a faggy thread.

 

[Narf!]

[quote1270652164=Pyro]
[quote1270649287=Narf!]
He's not going to see anything. You left out the warm goat blood.
[/quote1270649287]
please, leave this to the professionals narf.
[/quote1270652164]
My 5.2k GS says I'm pro enough.

 

[Brains]

[quote1270652878=Pyro]
Alright, you'll need an ounce of raisins, three ravens' eyes, one strand of unicorn hair, some firewood, matches, and a cauldron filled with water. Heat to a boil, place contents into cauldron, stir for exactly three minutes and twelve seconds, dip a sheet with the problem written on it into the cauldron and quickly retract it.
Now... tell me what you see.
[/quote1270652878]

Hahaha u troll

 

[Keeripes!]

Pyro, I tried it (let me tell you it was a bitch to get that unicorn hair), but it didn't seem to do anything but waste good unicorn hair. Let me tell you though, I rubbed one out fierce while I was waiting for something to happen.

Thanks for the advice though, I feel way less stressed than before.

Shotgun is a faggy thread. Pink nylon faggy thread. With AIDS.

 

[Roach]

well keeripes, im in comp eng tech, i got buddies in telecom.
Im pretty good w calc, and i somewhat remember transfer functions.
After you sub your values after integrating, can u not solve for the constant of integration? then u have the particular formula??
Maybe i dont understand the problem, but if its a calculus problem i might be able to help.

 

[Roach]

yeah nvm bro, after reading ur post again....i cant help. I just got done a calc test, so im thinking all mathy right now. Sry bro, hope u get it worked out.

 

[Hawk-Eye]

lol control systems was a joke at McGill LoL
the teacher was retiring and I think she didnt care jack all about the course so like it's was pretty easy LoL

 

[Shortbus]

[quote1270672464=Hawk-Eye]
LoL joke LoL like LoL


[/quote1270672464]

 

[Death]

Shortbus ... when he is discussing the need for engineers, he is not talking about you playing with your train set on the living room carpet making whoot whoot noises .. you really do live in a shortbus eh!!

 

[Shortbus]

I am a damn good engineer when it comes to those badboys.