Patent attributes
A self-propelling trolley assembly has a battery; a wheel driven by an electric motor that is powered by the battery; a rotation position or velocity sensor arranged to sense a rotation position or rotation velocity of the wheel; a user interface; and a control unit to affect a rotation of the wheel according to particular drive modes including a feedback assisted propulsion drive mode; a free-wheeling drive mode; and a rocking drive mode. The drive modes are implemented using different drive voltage patterns to the electric motor, and a stator of the electric motor has a number of stator poles that are not an integer multiple of a number of rotor poles and the stator poles are grouped into at least three magnetically and electrically identical subsets that are mounted sequentially around an angular direction of the electric motor.
