I am using this stepper motor, according to the specs I should get at least the 0.5 N.m at 200 rpm and 0.2N.m at 400 rpm.
Working at 12V or 24V make no big differences, I could not reach the torque/rpm given by the supplier.
I have notice few things, the intensity is around 0.7A during rotation while the stepper is given for 1.8A.
My question is the following: how should I setup the DC generator and the current to get the curve given by the stepper supplier?
Concerning the command I am using arduino uno and the program given in your tutorial.
Stepper : http://en.nanotec.com/steppermotor_st4118.html
the stepper reference is : ST4118D1804
Thanks in advance.