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An apparatus and a method for electromagnetically actuating engine valves to obtain soft seating. The magnitude and duration of current pulses applied to the armature attracting coils are determined based upon a total mechanical energy and a total energy loss of the armature obtained from the armatu

An apparatus and a method for electromagnetically actuating engine valves to obtain soft seating. The magnitude and duration of current pulses applied to the armature attracting coils are determined based upon a total mechanical energy and a total energy loss of the armature obtained from the armature position.

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An apparatus and a method for electromagnetically actuating engine valves to obtain soft seating. The magnitude and duration of current pulses applied to the armature attracting coils are determined based upon a total mechanical energy and a total energy loss of the armature obtained from the armatu

An apparatus and a method for electromagnetically actuating engine valves to obtain soft seating. The magnitude and duration of current pulses applied to the armature attracting coils are determined based upon a total mechanical energy and a total energy loss of the armature obtained from the armature position. layer structure including: ferromagnetic first and second antiparallel (AP) pinned layers;an antiparallel coupling (APC) layer located between and interfacing the first and second AP pinned layers;the first and second AP pinned layers self pinning one another without assistance of an antiferromagnetic (AFM) pinning layer or magnetic fields generated by a sense current; andan in-stack longitudinal biasing layer structure located within a track width of the sensor and magnetostatically coupled to the free layer for longitudinal biasing the magnetic moment of the free layer parallel to the head surface and parallel to major planes of the layers of the sensor; and first and second leads connected to the sensor for conducting a current through the sensor perpendicular to major planes of the layers of the sensor; the biasing layer structure including: a ferromagnetic pinned layer that has a magnetic moment;a nonmagnetic electrically conductive coupling layer located between and interfacing the pinned layer and the free layer so that the pinned layer and the free layer are only magnetostatically coupled; andan antiferromagnetic (AFM) pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer parallel to the head surface and parallel to the major planes of the layers of the sensor.10. A magnetic head assembly as claimed in claim 9 wherein: the AEM pinning layer is platinum manganese (PtMn); and the coupling layer of the biasing layer structure is tantalum (Ta). 11. A magnetic disk drive including at least one magnetic head assembly that has a head surface for facing a magnetic medium and that includes a write head and a read head, comprising: the write head including: ferromagnetic first and second pole piece layers that have a yoke portion located between a pole tip portion and a back gap portion;a nonmagnetic write gap layer located between the pole tip portions of the first and second pole piece layers;an insulation stack with at least one coil layer embedded therein located between the yoke portions of the first and second pole piece layers; andthe first and second pole piece layers being connected at their back gap portions; the read head including: ferromagnetic first and second shield layers; anda spin valve sensor located between the first and second shield layers; the spin valve sensor including: an antiparallel (AP) pinned layer structure;a ferromagnetic free layer having a magnetic moment that is free to rotate in response to a field signal; anda nonmagnetic electrically conductive spacer layer located between the free layer and the AP pinned layer structure; the antiparallel (AP) pinned layer structure including: ferromagnetic first and second antiparallel (AP) pinned layers;an antiparallel coupling (APC) layer located between and interfacing the first and second AP pinned layers;the first and second AP pinned layers self pinning one another without assistance of an antiferromagnetic (AFM) pinning layer or magnetic fields generated by a sense current; andan in-stack longitudinal biasing layer structure located within a track width of the sensor and magnetostatically coupled to the free layer for longitudinal biasing the magnetic moment of the free layer parallel to the ABS and parallel to major planes of the layers of the sensor; first and second leads connected to the sensor for conducting a current through the sensor perpendicular to major planes of the layers of the sensor; a housing; the magnetic medium being supported in the housing; a support mounted in the housing for supporting the magnetic head assembly with said head surface facing the magnetic medium so that the magnetic head assembly is in a transducing relationship with the magnetic medium; a motor for moving the magnetic medium; and a processor connected to the magnetic head assembly and to the motor for exchanging signals with the magnetic head assembly and for controlling movem