electro permanent magnets -update

Today, I researched the possibilities to lock a servo with electro- permanent magnets. This solution still seems possible, but isn't recently used for this application. Therefore I cannot guarantee at this moment that this technique will work. However I contacted a manufacturer of electro and permanent magnets about the possibilities and he will contact me soon. At the electrical engineering department I spoke with around 10 different professors in different fields of expertise and all of them didn't really know how to apply this on a servo motor. This was a little disappointing for me, and the best thing was to use a stepper-motor with permanent magnets inside. After looking into this I figured out that short cutting the wires of a stepper motor increases the friction inside the stepper motor, but still this force isn't strong enough to maintain course at sea.

Hopefully the manufacturer of these products can explain more about this technique so I can design the new servo with with zero static power consumption.

I also found another application of electro permanent magnets which are the cubelets (http://www.hizook.com/blog/2010/12/07/electropermanent-magnets-programmable-magnets-zero-static-power-consumption-enable-s)

This website explains how you can build a steppe rmotor with the use of electro permanent magnets so this application has the lock function within the motor itself instead of my version with an external lock mechanism.
Essentially this combined my research into stepper motors and the electro permanent magnets. Unfortunatly for me it is already patent pending....

Quote:

Electropermanent Magnet Stepper Motors:

One very interesting outcome of Ara's thesis was the development of (patent pending) EP magnet stepper motors.  This tiny "wobble" stepper motor uses EP magnets in place of traditional stator windings (electromagnets).

  

By switching the state of nearby EP magnets, the motor will step through various (rotational) configurations.   

Owing to the unique properties of EP magnets, this type of stepper motor offers some interesting benefits.

1. At low RPM (very little on-off switching), EP magnet motors have higher efficiency compared to electromagnetic motors.

1. At zero RPM ("stall"), EP magnet motors still outputs constant force / torque.  In electromagnetic motors, stall conditions result in massive power consumption -- this is a major problem for motor startup.

unquote
source:http://www.hizook.com/blog/2010/12/07/electropermanent-magnets-programmable-magnets-zero-static-power-consumption-enable-
http://www.hizook.com/files/users/3/Electropermanent_Magnets_Knaian.pdf