High reliability actuator

An actuator for moving a first component relative to a second component along a centerline comprising:

• a first actuating mechanism secured to the first component and having a first motor and a first nut rotatable with the first motor;
• a second actuating mechanism secured to the second component and having a second motor and a second nut rotatable with the second motor;
• a tubular screw threadably engaged with the first nut and the second nut such that rotation of at least one of the first motor and the second motor causes longitudinal movement between the first and second nuts along the screw to longitudinally move the second component relative to the first component, the screw having a first end and a second end;
• a first linear variable differential transformer secured to the first actuating mechanism and extending into the first end of the screw;
• and
• a second linear variable transformer secured to the second actuating mechanism and extending into the second end of the screw, each linear variable differential transformer including a bushing extending into the screw and having a polygonal shape allowing for relative longitudinal movement between the bushing and the screw but preventing relative rotational movement between the bushing and the screw.

An actuator for moving a first component relative to a second component comprising:

• a first actuating mechanism secured to the first component and having a first motor and a first nut rotatable with the first motor;
• a second actuating mechanism secured to the second component and having a second motor and a second nut rotatable with the second motor;
• a tubular screw having first and second ends and being threadably engaged with the first nut and the second nut such that rotation of at least one of the first motor and the second motor causes movement between the first and second nuts to move the second component relative to the first component;
• and
• a pair of linear variable differential transformers extending into the first and second ends of the screw, each linear variable differential transformer including:
• a solid magnetic core surrounding by a plurality of windings;
• a first bushing secured to one of the first and second actuating mechanisms and extending around the core and windings;
• and
• a second bushing slidably connected to the first bushing and movable with the screw;
• wherein the position of the second bushings relative to the first bushings is measured by applying voltage to one of the windings and sensing voltage on the remaining windings.

An actuator for moving a first component relative to a second component comprising:

• a first actuating mechanism secured to the first component and having a first motor and a first nut rotatable with the first motor;
• a second actuating mechanism secured to the second component and having a second motor and a second nut rotatable with the second motor;
• and
• a roller screw threadably engaged with the first nut and the second nut such that rotation of at least one of the first motor and the second motor causes movement between the first and second nuts to move the second component relative to the first component.

A linear voltage differential transformer comprising:

• a tubular screw having an end;
• a magnetic first bushing extending into and fixed to the end;
• a non-magnetic second bushing slidably connected to the first bushing;
• a solid magnetic core extending within the second bushing;
• and
• a plurality of windings surrounding the core within the second bushing;
• wherein the position of the second bushing relative to the first bushing is measured by applying voltage to the windings.