Abstract: A technique for measuring and selectively adjusting a clearance between a stationary object and desirably a rotating object includes a non-contact, sensing system having a sensor attachable to the stationary object, a mask having a predetermined sized viewport or aperture that sets or limits the sensing or operation of the sensor, and a controller. The sensor is operable for sensing within a field of view a portion of the rotating object and generating a signal in response thereto. The field of view varies in response to varying the clearance between the sensor and the second object. Desirably, the portion of the second object includes a varying pattern. The controller is operable to determine the clearance between the first object and the second object in response to the signal. In another embodiment, sensing system is operable to adjust the clearance by controller providing an electrical current to a resistive heating element in the thermally expandable portion of a plurality of segmented labyrinth seals.

Abstract: A technique for measuring and selectively adjusting a clearance between a stationary object and desirably a rotating object includes a non-contact, sensing system having a sensor attachable to the stationary object, a mask having a predetermined sized viewport or aperture that sets or limits the sensing or operation of the sensor, and a controller. The sensor is operable for sensing within a field of view a portion of the rotating object and generating a signal in response thereto. The field of view varies in response to varying the clearance between the sensor and the second object. Desirably, the portion of the second object includes a varying pattern. The controller is operable to determine the clearance between the first object and the second object in response to the signal. In another embodiment, sensing system is operable to adjust the clearance by controller providing an electrical current to a resistive heating element in the thermally expandable portion of a plurality of segmented labyrinth seals.

Abstract: A technique for measuring and selectively adjusting a clearance between a stationary object and desirably a rotating object includes a non-contact, sensing system having a sensor attachable to the stationary object, a mask having a predetermined sized viewport or aperture that sets or limits the sensing or operation of the sensor, and a controller. The sensor is operable for sensing within a field of view a portion of the rotating object and generating a signal in response thereto. The field of view varies in response to varying the clearance between the sensor and the second object. Desirably, the portion of the second object includes a varying pattern. The controller is operable to determine the clearance between the first object and the second object in response to the signal. In another embodiment, sensing system is operable to adjust the clearance by controller providing an electrical current to a resistive heating element in the thermally expandable portion of a plurality of segmented labyrinth seals.

Abstract: A method for detecting misalignment of initially-aligned fiber filaments in a composite. An optical fiber is placed among the fiber filaments in the composite, light is directed into the optical fiber, the intensity of the light in the optical fiber is measured during subsequent composite processing, and attenuation in such light intensity is ascertained which indicates such misalignment (e.g., wrinkling, bending, buckling, porosity, delamination and the like) is being detected during such processing. In another preferred method, before-processing and after-processing x-ray images are taken of an x-ray-attenuating fiber which has been placed among x-ray-transparent fiber filaments in a composite.

Abstract: A method for detecting misalignment of initially-aligned fiber filaments in a composite. An optical fiber is placed among the fiber filaments in the composite, light is directed into the optical fiber, the intensity of the light in the optical fiber is measured during subsequent composite processing, and attenuation in such light intensity is ascertained which indicates such misalignment (e.g., wrinkling, bending, buckling, porosity, delamination and the like) is being detected during such processing. In another preferred method, before-processing and after-processing x-ray images are taken of an x-ray-attenuating fiber which has been placed among x-ray-transparent fiber filaments in a composite.