I need to do a transfer function of the circuit I've attached but I'm not sure how to treat the op-amp that's included. If anybody has any ideas please pass them on. I need the transfer function to understand how the circuit affects the frequecny response of the input signal for variations of Kb, Kt and Km.

The input signal will be 1Volt peak. I was going to try using nodal analysis once I know how to treat the op-amp. Any thoughts on the matter will be greatly appreciated

Cheers.

 

Just assume that the inverting input equals the non-inverting input. So node 11 is ground. But it doesn't pull any current.

So you will have three equations with Vin and Vout, one for each current into node 11. Then add them all up for a zero sum, and you should be able to solve it. Look like it will likely be messy though.

BTW, it looks like a summing opamp configuration with a twist.