You can use a controller board such as RD1104 from dSPACE i guess for this purpose. the advantage of this sort of this system is that, you directly use simulink models to control the torque. Other option i know about is using the GECKO Mainboard. http://www.microlab.ch/cad_ex/5sem/ex550/ex_index.htm
details can be found from that link. Hope that info helps.
