Magnetostrictive motor for a borehole assembly

A bottom hole assembly, comprising:

• a motor comprising a rotor;
• a housing of the motor about a carriage;
• a shaft coupled to the rotor, wherein the shaft comprises an undulated surface with a skewed pattern associated with one rotational direction;
• a magnetostrictive rod assembly coupled to the rotor, wherein the magnetostrictive rod assembly remains stationary, and wherein the magnetostrictive rod assembly comprises a magnetostrictive rod disposed in the carriage about the undulated surface, the magnetostrictive rod having an end disposed adjacent to the undulated surface;
• a winding arrangement disposed at least partially about the magnetostrictive rod to induce a series of shape changes in the magnetostrictive rod, wherein the series of shape changes imparts forces to the undulated surface;
• a control device coupled to a power source and the winding arrangement, wherein the control device comprises electronics to drive the magnetostrictive rod assembly, wherein the control device is configured to coordinate a linear shape change of the induced series of shape changes in the magnetostrictive rod with an undulation of the rotor, and wherein the rotor drives the shaft;
• and
• an adjustable portion of the housing, wherein the rotor is drivingly coupled to the adjustable portion of the housing to orient the adjustable portion of the housing.

A method of providing rotational force, the method comprising:

• providing a motor of a bottom hole assembly, the motor comprising:
• a rotor comprising an undulated surface with a skewed pattern associated with one rotational direction;
• a magnetostrictive rod assembly coupled to the rotor, wherein the magnetostrictive rod assembly remains stationary, and wherein the magnetostrictive rod assembly comprises a rod disposed about the rotor;
• a coil disposed about the rod to generate a varying field that induces shape changes in the rod, which in turn impart forces to the undulated surface that rotate the rotor;
• a control device coupled to a power source and the coil, wherein the control device comprises electronics to drive the magnetostrictive rod assembly;
• and
• providing a housing and a shaft disposed therein, the shaft coupled to the rotor, wherein the rotor and the shaft are drivingly coupled to an adjustable portion of the housing;
• and
• inducing shape changes in the rod to rotate the rotor and the shaft, wherein the control device coordinates a linear shape change of the induced shape changes in the rod with an undulation of the rotor to orient the adjustable portion of the housing.