I read about these a little while ago. They are not Chinese; they are made in the USA. I seem to remember they were a Kickstarter campaign, and I read a bit about them on Hackaday. Seemed like a good idea, but they are expensive. Maybe the Chinese copies are cheaper, of course. The maths they are based on is interesting, and somewhat complex, but clever.
Marcus On 27 May 2017, at 20:52, Chris Albertson wrote: > Hi, > > Has anyone here experience with this? > > I think these are new. I've seen them on some web sites and also eBay. I > can't find any good engineering information yet, like user manuals or > speed/torque plots but the idea is great. > > They are an integrated closed loop driver/controller and motor. The > feedback loop is done inside the motor. They are MUCH better at holding > torque at high speed than are normal steppers. More like a servo but at > much lower cost. The motor accepts DC power (about 36 volts) and step > and direction. Here is one example from eBay > > Building the driver into the motor is good. For closed loop control the > driver must be matched to the motor so you would always buy them in pairs > anyway. Placing them in one unit saves the need to run a lot of wire and > all the noise problems and lowers the over all cost. The driver cane made > simpler and cheaper because it does not need to be general purpose, it just > drive the motor with known inductance and resistance. > > http://www.ebay.com/itm/Nema23-57BYG-Stepper-Motor-Integrated-Driver..... > <http://www.ebay.com/itm/Nema23-57BYG-Stepper-Motor-Integrated-Driver-2-in-1-L112mm-3Nm-24-48VDC-CNC/192011640913?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D40130%26meid%3Dbc8047bd176346b9a8fbf5703256f1ef%26pid%3D100005%26rk%3D4%26rkt%3D6%26sd%3D262565354603> > > I saw a youtube video demo of one of these that showed it holding > position. It was using almost no current and the motor was cool. But then > if you apply force to the shaft the current zooms up to counter the applied > force, like a servo Basically it IS a servo. There is an optical > encoder. The above web page has a block diagram. > > All the good info is in Chinese. Perhaps someone here is good at technical > Chinese. My wife can read only the very basic stuff and Google translation > is not so good. I think these are designed and sold into the Chinese > domestic market hence no US sales office or English technical documents. > > This eBay unit is cheaper than a conventional setup. I think this is the > way things are moving > > > -- > > Chris Albertson > Redondo Beach, California > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
