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#### Very Long Equations of motion -> Simulink

Hey all,
I'm building a simulator for a robot that I am working on. I have
derived the equations of motion for the 6-DOF open-chain manipulator.
They are in the form

D(q)*q" + C(q,q')*q' + g(q) = Torque

Where D and C are 6x6 matrices and g and Torque are 6x1 vectors.

I would like to implement these equations into Simulink.

Problem: The terms in D and C are huge. I'm talking 10+ pages per
term. They are all non-linear, invovling sin and cos.

Is there any way to put these equations into Simulink without
creating 10,000 blocks for each term.

I am hoping that there is a way that I can say this is the function
f=(q1, q1', q2, q2'...q6,q6') give it every input and have it spit
out q1", q2" and so forth. Or something of that sort. I'm not
exactly sure how it would work, but maybe someone has experience with
this.

Thanks for the help guys.

--Patrick

 0
10/24/2006 1:45:03 AM
comp.soft-sys.matlab 211264 articles. 26 followers. lunamoonmoon (257) is leader.

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Just bumping this one up because I didn't get any replies the first
time around.

If I'm not explaining the problem well, someone speak up. I'll
attempt to reexplain it.

--Patrick

 0
10/24/2006 11:20:08 PM
Dude better go for programming than simulink.6-DoF is herculean
task.I dont know how u r working on that.what controller u r
designing?

 0
1/31/2007 6:16:27 PM
For case like this, I would suggest an implementation using
s-function. Derive a non-linear state equation first and then write
the equation into the s-function. If you are not familar with
S-function, take a look at the help document. It's not much more than
writing out your equations with sin() and cos().

Patrick Ryan wrote:
>
>
> Hey all,
> I'm building a simulator for a robot that I am working on. I have
> derived the equations of motion for the 6-DOF open-chain
> manipulator.
> They are in the form
>
> D(q)*q" + C(q,q')*q' + g(q) = Torque
>
> Where D and C are 6x6 matrices and g and Torque are 6x1 vectors.
>
> I would like to implement these equations into Simulink.
>
> Problem: The terms in D and C are huge. I'm talking 10+ pages per
> term. They are all non-linear, invovling sin and cos.
>
> Is there any way to put these equations into Simulink without
> creating 10,000 blocks for each term.
>
> I am hoping that there is a way that I can say this is the function
> f=(q1, q1', q2, q2'...q6,q6') give it every input and have it spit
> out q1", q2" and so forth. Or something of that sort. I'm not
> exactly sure how it would work, but maybe someone has experience
> with
> this.
>
> Thanks for the help guys.
>
> --Patrick

 0
Fangjun
1/31/2007 6:36:06 PM
Unfortunately, I've just came across such situations, do you remember you figure out that? Although, I'm working with 4-dof articulated robot, but I'm getting very long stuff?
 0
amin013 (1)
3/17/2015 1:58:27 AM

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