초록 ▼

A force transmitting linkage connects a piezoelectric actuator to a flap that is pivotably connected to a helicopter rotor blade. In a flap actuation control arrangement and method, a force transducer senses the force being transmitted through the linkage and generates a corresponding actual force s

A force transmitting linkage connects a piezoelectric actuator to a flap that is pivotably connected to a helicopter rotor blade. In a flap actuation control arrangement and method, a force transducer senses the force being transmitted through the linkage and generates a corresponding actual force signal, a flap position sensor senses the position of the flap and generates a corresponding actual flap position signal, a first controller receives a desired flap position signal and the actual flap position signal and responsively thereto generates a reference signal, and a second controller receives the reference signal and the actual force signal and responsively thereto generates a control signal that is provided to the piezoelectric actuator. This provides a real time flap actuation control with respect to highly dynamic forces as well as friction forces acting on the flap.

대표청구항 ▼

A force transmitting linkage connects a piezoelectric actuator to a flap that is pivotably connected to a helicopter rotor blade. In a flap actuation control arrangement and method, a force transducer senses the force being transmitted through the linkage and generates a corresponding actual force s

A force transmitting linkage connects a piezoelectric actuator to a flap that is pivotably connected to a helicopter rotor blade. In a flap actuation control arrangement and method, a force transducer senses the force being transmitted through the linkage and generates a corresponding actual force signal, a flap position sensor senses the position of the flap and generates a corresponding actual flap position signal, a first controller receives a desired flap position signal and the actual flap position signal and responsively thereto generates a reference signal, and a second controller receives the reference signal and the actual force signal and responsively thereto generates a control signal that is provided to the piezoelectric actuator. This provides a real time flap actuation control with respect to highly dynamic forces as well as friction forces acting on the flap. ange of travel between first and second vertically spaced positions, wherein said second position is at a higher elevation than said first position, wherein an entirety of both of said executing a first and a second monitoring steps are executed at a higher elevation than said second position. 9. A method, as claimed in claim 1, wherein: each of said executing first and second monitoring steps comprises directing a beam of light and determining if light of more than a predetermined magnitude is reflected back in a substantially opposite direction used by said directing step. 10. A method, as claimed in claim 1, further comprising the steps of: loading a first said container on said elevator at a first vertical position, wherein said moving said elevator in a first direction step comprises moving said elevator down a first increment in response to a receipt of said first signal based upon an existence of said first said container at said first vertical position; loading a second said container on said first said container at said first vertical position after said moving said elevator down a first increment step, wherein said moving said elevator in a first direction step comprises moving said elevator down a second increment in response to a receipt of another said first signal based upon an existence of said second said container at said first vertical position. 11. A method, as claimed in claim 1, further comprising the steps of: loading a first said container on said elevator at a first vertical position; and loading a second said container on said first said container and at a second vertical position which is greater than said first vertical position, wherein said moving said elevator in a first direction step comprises moving said elevator down a first increment in response to a receipt of one said first signal based upon an existence of said first said container at said first vertical position and which then disposes said second said container at said first vertical position, and wherein said moving said elevator in a first direction step further comprises moving said elevator down a second increment in response to a receipt of another said first signal based upon an existence of said second said container at said first vertical position. 12. A method, as claimed in claim 1, wherein: a second said container is stacked on top of a first said container on said elevator, wherein said second said container is disposed at said second vertical position, wherein said method further is comprises the step of unloading said second said container from said elevator while said second said container is at said second vertical position, wherein said moving said elevator in a second direction step comprises moving said elevator such that said first said container is now disposed at said second vertical position in response to a receipt of said first signal by said elevator after said unloading step. 13. A method, as claimed in claim 1, further comprising the steps of: loading said plurality of said containers on said elevator in stacked relation, one on top of another, wherein said moving said elevator in a first direction step comprises moving said elevator down one increment each time said executing a first monitoring step determines that one of said plurality of containers is still disposed at said first vertical position after a recentmost execution of said moving said elevator down one increment step; and unloading said plurality of containers, wherein said moving said elevator in a second direction step comprises moving said elevator up one increment each time said executing a second monitoring step determines that one of said plurality of said containers has been removed from said second vertical position. 14. A method for assembling a disk drive, comprising the steps of: using a material delivery system at a workstation in a filtered environment wherein said material delivery system comprises: an elevator comprising a platform, wherein said platform comprises a plurality of perforations, wherein a plurality of containers are stacked on said elevator for delivery to said workstation, wherein each said container comprises a plurality of disk drive components; first means for monitoring for an existence of any said container on said elevator at a first vertical position, wherein said first means for monitoring is operatively interconnected with said elevator; second means for monitoring for an absence of any said container on said elevator at a second vertical position, wherein said second means for monitoring is operatively interconnected with said elevator; first means for moving said elevator in a first direction based upon a first output from said first means for monitoring that is provided to said elevator; and second means for moving said elevator in a second direction based upon a second output from said second means for monitoring that is provided to said elevator, wherein said second direction is at least generally opposite said first directions; removing a first said disk drive component from an uppermost said container stacked on said elevator; and assembling at least part of a first disk drive using said first said disk drive component, wherein said assembling step is executed at said workstation. 15. A method, as claimed in claim 14, wherein: said workstation is a clean room. 16. A method, as claimed in claim 14, wherein: said workstation is a minienvironment. 17. A method, as claimed in claim 14, wherein; said workstation has a cleanlinesss level of at least a class 100. 18. A method, as claimed in claim 14, wherein: said first and second means for monitoring comprises first and second container sensors, respectively. 19. A method, as claimed in claim 18, wherein: said first and second container sensors are directed at different, vertically spaced elevations. 20. A method, as claimed in claim 19, wherein said material delivery system further comprise: a housing comprising an open upper end and a hollow interior, wherein said elevator is movably disposed within said hollow interior of said housing, and wherein each of said first and second container sensors are disposed any higher elevation than said open upper end of said lousing. 21. A method, as claimed in claim 14, wherein: said fist vertical position is at a higher elevation than said second vertical position, wherein said first direction is at least generally vertically downward, and wherein said second direction is at least generally vertically upward. 22. A method, as claimed in claimed 14, wherein said material delivery system further comprises: a housing comprising an open upper end and a hollow interior, wherein said elevator is movably disposed within said hollow interior; and a support disposed at least generally proximate said open upper end, wherein said support comprises a plurality of perforations. 23. A method for assembling a disk drive comprising the steps of: using a material delivery system at a workstation in a filtered environment, wherein said material delivery system comprises: a housing comprising an open upper end and a hollow interior; a support disposed at least generally proximate said open upper end, wherein said support comprises a plurality of perforations; an elevator movably disposed within said hollow interior of said housing, wherein said elevator comprises a platform, wherein a plurality of containers are stacked on said elevator for delivery to said workstation, wherein each said container comprises a plurality of disk drive components; an elevator drive assembly; and first and second container sensors that are operatively interconnected with said elevator drive assembly for initiating advancement of said elevator in opposite directions, wherein said first and second sensors are directed vertically beyond said upper end of said housing; removing a first s