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Shri
Posts:
4
Registered:
12/4/12


Re: transfer function
Posted:
Dec 5, 2012 9:04 AM


On Wednesday, December 5, 2012 1:41:19 PM UTC, Nasser M. Abbasi wrote: > On 12/5/2012 7:17 AM, shri preethi wrote: > > > > > can some one help me out to find the transfer function fore a pneumatic pump > > >and the matlab progr
> > > You find the TF for any system the same way. You start with > > the mathematica model. i.e. you derive the equation of motion. > > (or the relation between the input/output in time domain) > > This is step (1) > > > > You'll end up with a differential equation. For SISO, you'll > > have something like ay''+by'+cy=f(y,t). For MIMO you'll need > > to use state space (ss functions, i.e. A,B,C,D), much easier. > > > > Then you translate this to Laplace domain, then you find > > the ratio of the Laplace Y(s) of the output (y(t) in the above) to > > the Laplace F(s) of the input (f(y,t) in this case). > > > > This ratio is the transfer function, will be a function of 's', > > the Laplace domain variable. It should have a numerator polynomial > > in 's' of order <= that in the denominator polynomial, else you > > did something wrong in the model. > > > > So, did you step (1) above? if so, what is the equation? > > > > or you want one to also derive the equation for the pump as well? > > > > If so, what is the specifications? (sizes, pressure, input, etc...?) > > > > I do not do mechanical pumps myself, at school mostly we do basic > > mechanical systems (mass/damper/spring things) so I can't help you with > > the model itself but may be someone else would, but you have to give > > specifications. Engineers like to see specifications before doing > > design. > > > > > > www.engineersedge.com/hydraulic/hydraulic_pneumatic_cylinder_force_10105.htm the specificetion r thr in this link...using tis i need to find the transfer function....can u plz help it out...



