Techniques for updating wake separation distance between aircraft are described. A sensors mesh within a flight path of an aircraft is used to detect when a wake vortex from the aircraft has drifted onto the sensor mesh. A minimum wake separation distance and separation interval for following aircraft are determined based on the various sensor measurements, environmental conditions, and aircraft properties. The minimum wake separation distance and separation interval are used to minimize aircraft separation distances between aircraft that are required due to wake vortex turbulence caused by aircraft during flight.

Techniques for updating wake separation distance between aircraft are described. A sensors mesh within a flight path of an aircraft is used to detect when a wake vortex from the aircraft has drifted onto the sensor mesh. A minimum wake separation distance and separation interval for following aircraft are determined based on the various sensor measurements, environmental conditions, and aircraft properties. The minimum wake separation distance and separation interval are used to minimize aircraft separation distances between aircraft that are required due to wake vortex turbulence caused by aircraft during flight.

Magnetic position sensors, systems and methods are disclosed. In an embodiment, a position sensing system includes a magnetic field source; and a sensor module spaced apart from the magnetic field source, at least one of the magnetic field source or the sensor module configured to move relative to the other along a path, the sensor module configured to determine a position of the magnetic field source relative to the sensor module from a nonlinear function of a ratio of a first component of a magnetic field of the magnetic field source to a second component of the magnetic field of the magnetic field source.

Magnetic position sensors, systems and methods are disclosed. In an embodiment, a position sensing system includes a magnetic field source; and a sensor module spaced apart from the magnetic field source, at least one of the magnetic field source or the sensor module configured to move relative to the other along a path, the sensor module configured to determine a position of the magnetic field source relative to the sensor module from a nonlinear function of a ratio of a first component of a magnetic field of the magnetic field source to a second component of the magnetic field of the magnetic field source.

Techniques for updating wake separation distance between aircraft are described. A sensors mesh within a flight path of an aircraft is used to detect when a wake vortex from the aircraft has drifted onto the sensor mesh. A minimum wake separation distance and separation interval for following aircraft are determined based on the various sensor measurements, environmental conditions, and aircraft properties. The minimum wake separation distance and separation interval are used to minimize aircraft separation distances between aircraft that are required due to wake vortex turbulence caused by aircraft during flight.

Techniques for updating wake separation distance between aircraft are described. A sensors mesh within a flight path of an aircraft is used to detect when a wake vortex from the aircraft has drifted onto the sensor mesh. A minimum wake separation distance and separation interval for following aircraft are determined based on the various sensor measurements, environmental conditions, and aircraft properties. The minimum wake separation distance and separation interval are used to minimize aircraft separation distances between aircraft that are required due to wake vortex turbulence caused by aircraft during flight.

A method for determining a distance comprises: providing at least two phase measurements made with modulated light of different modulation wavelengths, each phase measurement being indicative of the distance up to an integer multiple of a respective modulation wavelength; providing a set of possible wraparound count combinations; for each one of the possible wraparound count combinations, calculating a combination of unwrapped phase hypotheses corresponding to the at least two phase measurements; and selecting a most plausible combination of unwrapped phase hypotheses among the combinations of unwrapped phase hypotheses and calculating the distance based upon the selected most plausible combination of unwrapped phase hypotheses.

A wear detection device is disclosed herein. The wear detection device may comprise: a housing including a transparent tube, the housing configured to receive a photoconductive fluid; a first casing disposed at a first end of the housing; and a power source disposed in the first casing, the power source configured to power a transmitter in response to the transparent tube being exposed to light. An electrical circuit may be closed in response to an entire length of the transparent tube being exposed to light or only a portion of the transparent tube being exposed to the light.

A wear detection device is disclosed herein. The wear detection device may comprise: a housing including a transparent tube, the housing configured to receive a photoconductive fluid; a first casing disposed at a first end of the housing; and a power source disposed in the first casing, the power source configured to power a transmitter in response to the transparent tube being exposed to light. An electrical circuit may be closed in response to an entire length of the transparent tube being exposed to light or only a portion of the transparent tube being exposed to the light.

Non-contacting caliper measurements of free standing sheets such as porous polymer and paper detect mid-IR interferometric fringes created by the reflection of light from the top and bottom surfaces of the sheet. The technique includes directing a laser beam at a selected angle of incidence onto a single spot on the exposed outer surface wherein the laser beam comprises radiation having a wavelength in the 3-50 micron range and scanning the laser beam through a selected angle range as the laser beam is directed onto the exposed outer surface and measuring the intensity of an interference pattern that forms from the superposition of radiation that is reflected from the exposed outer surface and from the inner surface. Thickness can be extracted from the fringe separation in the interference pattern. Rotating and focusing elements ensure that the spot position on the sheet remains the same while varying the incident angle.