Abstract: A method of operating a three phase sensorless brushless motor including a stator including three phase windings and a rotor carrying at least one permanent magnet, the method including switching power to the phase windings of the stator in synchronisation with the rotor position, by applying voltage strokes to the windings, to generate a rotating magnetic flux which interacts with the rotor flux generated by the rotor magnet, to rotate the rotor, the method including applying a plurality of voltage strokes to each of the windings for each rotation of the rotor, sensing a position of the rotor by detecting back emf voltage transitions in a third only of the windings in periods in which voltage strokes are not applied to the third winding, and estimating when the rotor is expected to have rotated though a predetermined angle to a position at which a voltage stoke is next to be applied to the or another winding, and applying the voltage stroke at the estimated time.

Abstract: An intramuscular stimulation (IMS) device and method permit electrical and mechanical modes of stimulation to be carried out individually or together. The gun-like stimulation device permits a disposable needle applicator unit including a needle and elongate sheath to be removably attached thereto. Different needle penetration depths are obtainable with a single needle by virtue of a drive carriage with a position selecting element. To help avoid repetitive strain injury to a treating physician, a processor may monitor a body contact sensor and continue an intramuscular stimulation cycle only so long as contact is detected. In order to ensure that only a single IMS operation is performed during a period of body contact, performance of a further intramuscular stimulation cycle may be prevented unless it is determined that body contact was broken at a time following a previous IMS cycle.