instaspin accurate position control

Jose,

InstaSPIN-MOTION includes labs that will use the encoder to enable position control.  You should start with the sensored velocity lab 12 which will help you get the encoder integrated and configured.  Then move on to lab 13a-13d which explore the position control offerings in InstaSPIN-MOTION.

One note is that with the DRV8312 kit when using an encoder you should supply an external +5V since the on-board +5V regulator cannot meet the current draw requirements of most encoders.  

jose luis cordoba said:

i am interested on controlling the motor rotor position accurately, with less than 1 degree error, and be able to get rid off the encoder. is this possible to do with the instaspin solution?

In general the answer here is no.

With FAST, once you are moving at enough velocity where the flux generates enough of a Bemf signal we can be accurate to within a few electrical degrees, which is typically (depending on # poles) better than 1 mechanical degree.  But this is only for rotor position used in a velocity application.  At low speeds FAST can remain stable, but the angle estimation degrades.

There are other non-observer injection techniques that work well for the zero and low speed range.  One uses inductance changes due to highly salient rotor/stator combinations (which most off the shelf are not).  For non-salient there are iron saturation techniques but it is nearly impossible today to consistently get an accurate enough resolution for position control at low speeds.

You need to use a resolveror encoder for < 1 degree accuracy at zero and low speed.