Patent Description:
The present disclosure relates to the art of aircraft lighting systems. Aircraft lighting systems may illuminate environments inside and outside the aircraft.

Lighting systems may blink or flicker projected light to increase visual awareness. Energy provided to such lighting systems may be wasted due to heating losses, extraneous lighting, or other forms of energy. Lighting systems may be further subjected to vibrations or other energy forms. <CIT> relates to a system and method for monitoring structural health of bonded components.

Disclosed is an aircraft lighting system described herein and defined in claim <NUM>.

In addition to one or more of the features described above, or as an alternative, further embodiments may include control circuitry defining a control circuitry voltage, the control circuitry operable to output a control signal to the driver.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the regulator voltage is defined at the control circuitry voltage.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the control signal is pulse width modulated.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the control circuitry is a synchronization controller, and the control signal includes synchronization commands such that the driver operates according the synchronization commands.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the control circuitry is a timing controller, and the control signal includes timing commands such that the driver operates according to the timing commands.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the control circuitry is a signal conditioner, and the control signal is conditioned according to the signal conditioner.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the energy harvesting circuitry includes a switch operable to disconnect the control circuitry from the regulator when energy from the energy generation circuitry is below a predetermine threshold.

In addition to one or more of the features described above, or as an alternative, further embodiments may include monitoring circuitry defining a monitoring circuitry voltage, the monitoring circuitry operable to output diagnostic information related to the lighting system.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the regulator voltage is defined at the monitoring circuitry voltage.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the monitoring circuitry is an elapsed time counter, and the diagnostic information includes an actuation count of the illumination element.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the monitoring circuitry is a luminance monitor, and the diagnostic information includes a maximum luminance of the illumination element.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the monitoring circuitry is a temperature monitor, and the diagnostic information includes a temperature associated with the illumination element.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the monitoring circuitry is a water monitor, and the diagnostic information includes a water indication associated with the housing.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the energy harvesting circuitry includes a switch operable to disconnect the monitoring circuitry from the regulator when energy stored in a capacitor associated with the energy generation circuitry is below a predetermine threshold.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the energy harvesting circuitry supplements the energy from a power connection that provides the energization of the illumination element.

Also disclosed is an aircraft lighting system disposed in an environment of an aircraft. The aircraft lighting system includes a housing. The aircraft lighting system includes an illumination element disposed within the housing. The aircraft lighting system includes energy generation circuitry configured to generate electricity from the environment. The aircraft lighting system includes switching circuitry including a driver operable to control illumination of the illumination element and operated with a driver voltage. The aircraft lighting system includes control circuitry a control circuitry voltage, the control circuitry operable to output a control signal to the driver. The aircraft lighting system includes energy harvesting circuitry including a regulator configured to draw energy from the energy generation circuitry and output a regulator voltage defined at the driver voltage.

In addition to one or more of the features described above, or as an alternative, further embodiments may include monitoring circuitry defining a monitoring circuitry voltage and the regulator voltage is defined at the monitoring circuitry voltage, the monitoring circuitry operable to output diagnostic information related to the lighting system.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the energy generation circuitry includes a Seebeck generator that converts heat energy from the environment to electrical energy.

Also disclosed is an aircraft lighting system disposed in an environment of an aircraft. The aircraft lighting system includes a housing. The aircraft lighting system includes an illumination element disposed within the housing. The aircraft lighting system includes energy generation circuitry configured to generate electricity from the environment. The aircraft lighting system includes switching circuitry including a driver operable to control illumination of the illumination element and operated with a driver voltage. The aircraft lighting system includes monitoring circuitry defining a monitoring circuitry voltage, the monitoring circuitry operable to output diagnostic information related to the illumination element. The aircraft lighting system includes energy harvesting circuitry including a regulator configured to draw energy from the energy generation circuitry and output a regulator voltage defined at the driver voltage.

Aircraft may include lighting systems to illuminate internal and external environments. Such lighting systems may blink or flicker, requiring additional switching circuitry to control the flow of electricity to illumination elements. Switching circuitry may discharge heat due to switching losses along with other circuitry associated with the lighting system.

As disclosed herein, energy harvesting circuitry may be employed to capture wasted energy from heat, light, vibration, and other energy sources. For example, heat energy harvesting may be performed by Seebeck generators. Light energy harvesting may be performed, as an example, on refracted or reflected light within the lighting system housing by photovoltaic generators. As an example, vibration energy harvesting may be performed by piezoelectric generators. Further, the generation of blinking or flickering light may enable increased value return for energy harvesting circuitry on aircraft.

<FIG> illustrates an example of a commercial aircraft <NUM> having an aircraft lighting system or a lighting system <NUM>. The lighting system <NUM> may be disposed in various locations in any environment of the aircraft <NUM>. An environment may include or define particular atmospheric parameters (e.g., temperature, humidity, pressure). As an example, the lighting system <NUM> may be disposed on the interior of the aircraft <NUM> as wash lights or other implements. Lighting system <NUM> may be disposed on the exterior of the aircraft <NUM> as strobe or multifunction lights, including landing lights, taxi lights, strobe lights, beacon lights, and tail navigation lights.

As shown in <FIG>, the lighting system <NUM> may include any number of circuitries or other implementations to perform the requisite actions. Portions of the circuitry may be disposed within the housing <NUM>. Portions of the circuitry may be disposed outside of the housing <NUM>. For example, energy generation circuitry <NUM> may be a Seebeck generator having a hot plate inside the housing <NUM> and attached to the heatsink <NUM>, while the cold plate may be disposed outside the housing <NUM>. The energy generation circuitry <NUM> may further be disposed as a portion of the housing <NUM>. The lighting system <NUM> may include an illumination element <NUM>. The illumination element <NUM> may also include one or more illumination elements. The illumination element <NUM> may be a light-emitting diode (LED), High Intensity Discharge Lamps, Organic LEDs, incandescent filament, combinations thereof, or any other implement. The illumination element <NUM> may be connected with a printed circuit board <NUM>. The printed circuit board <NUM> may conduct heat from circuitry disposed thereon.

The lighting system <NUM> may include an input conduit that includes a power connection <NUM> to aircraft power systems. The power connection <NUM> may be connected to a <NUM>-volt bus associated with the aircraft <NUM>. The <NUM>-volt bus may conduct alternating current. The current may alternate at <NUM>. The power connection <NUM> may receive any type of power to energize the lighting system <NUM>. It should be appreciated that any of the circuitry or functional blocks shown in <FIG> may be added, removed, or duplicated based on the type of power received from the power connection <NUM>.

Referring to <FIG>, the aircraft <NUM> includes circuitry for monitoring, controlling, and energizing the illumination elements <NUM>. Power connection <NUM> is connected with a printed circuit board <NUM>. The printed circuit board <NUM> may include electromagnetic interference circuitry <NUM> for receiving the raw power input from power connection <NUM> and to remove noise. The rectifier <NUM> may convert the <NUM>-volt alternating current to <NUM>-volt direct current. A low-dropout regulator <NUM>, or another type of voltage regulator, may provide reduced voltages to the power factor correction integrated circuitry <NUM> and the driver integrated circuit <NUM>. The rectified, and potentially voltage-controlled, direct current from the rectifier <NUM> is provided to the power factor correction circuit <NUM>. The power factor correction circuit <NUM> is provided to switching circuitry <NUM>. The switching circuitry <NUM> may include any number of switches for energizing and deenergizing the illumination element <NUM>. The switching circuitry <NUM> may include a driver <NUM> for driving the illumination element <NUM>. The driver integrated circuit <NUM> may be operated by a driver voltage. The driver voltage may be a quiescent voltage or a quiescent power requirement associated with the driver <NUM> and the driver integrated circuit <NUM>. Quiescent voltage or power may include the non-switching or non-operating power requirements of the integrated circuit.

The printed circuit board <NUM> may include a heatsink <NUM>. The heatsink <NUM> may be thermally conductive with the entire printed circuit board <NUM>. The heatsink <NUM> is be thermally conductive with the illumination element(s) <NUM>. The heatsink <NUM> may be thermally conductive with any energy generating or heat generating parts associated with the printed circuit board <NUM>. One or more printed circuit boards <NUM> or printed circuit board portions may be used. The printed circuit board may include FR-<NUM> or metallic materials. The heatsink <NUM> may be associated with particular heat generative devices on the printed circuit board <NUM>. The heatsink <NUM> provides heat to the energy harvesting circuitry <NUM>. The energy generation circuitry <NUM> is a Seebeck generator having a hot side <NUM> connected to the heatsink <NUM> and a cold side <NUM>. The cold side <NUM> may be connected anywhere that is cooler than the heatsink <NUM>. The cold side may be connected to or arranged about the housing <NUM>. The illumination element <NUM> may be directly mounted on the printed circuity board <NUM>, heating one side of the printed circuit board <NUM> to cause the Seebeck Effect.

It should be appreciated that the heatsink <NUM> may be any type of energy-conductive device. As an example, the heatsink <NUM> may be a rigid, vibration-transmitting element when associated with energy generation circuitry <NUM> that is piezoelectric. As an example, the heatsink <NUM> may be a light-conduit such as an optical fiber for transmitting light generated by the illumination element <NUM> when associated with energy generation circuitry <NUM> that is photovoltaic.

The energy generation circuitry <NUM> may be connected with a capacitor <NUM> or another energy storage device to collect the energy generated by the energy generation circuitry <NUM>. The energy stored in the capacitor <NUM> may be transferred to the regulator <NUM>. The regulator <NUM> may convert the capacitor voltage to suitable regulator voltages for consumption by the switching circuitry <NUM>, the monitoring circuitry <NUM>, and the control circuitry <NUM>. For example, the control circuitry <NUM> may require <NUM>-volt, <NUM>-volt, or <NUM>-volt energization.

The regulator <NUM> may output a regulator voltage defined commensurate with the monitoring circuitry <NUM> voltages. As an example, the elapsed time counter <NUM> may require a <NUM>-volt supply. The regulator <NUM> may include regulatory circuitry operable to provide the <NUM>-volt supply. As another example, the luminance monitor <NUM> may require a <NUM>-volt supply. The regulator <NUM> may include regulatory circuitry operable to provide the <NUM>-volt supply. As another example, the temperature monitor <NUM> may require a <NUM>-volt supply. The regulator <NUM> may include regulatory circuitry operable to provide the <NUM>-volt supply. As another example, the water ingress monitoring or water monitor <NUM> may require a <NUM>-volt supply. The regulator <NUM> may include regulatory circuitry operable to provide the <NUM>-volt supply. Monitoring circuitry <NUM> may record information related to the operation of the lighting system <NUM> in a data repository or provide information to aircraft controllers.

The elapsed time counter <NUM> may provide diagnostic information that includes an actuation count of the illumination element <NUM>. That is, the number of illuminations or a running time of illumination of the illumination element <NUM> or lighting system <NUM>. The luminance monitor <NUM> may provide diagnostic information that includes a maximum luminance of the illumination element <NUM>. The luminance may be a maximum brightness or a calculated maximum brightness of the illumination element <NUM>. The temperature monitor <NUM> may provide diagnostic information that includes a temperature associated with the illumination element <NUM>. The water monitor <NUM> may provide diagnostic information that includes a water indication or water intrusion indication associated with the housing <NUM>. The water monitor <NUM> may also provide humidity information associated with the housing <NUM>.

The regulator <NUM> may output a regulator voltage defined according to the control circuitry <NUM> voltages. As an example, the timing controller <NUM> may require a <NUM>-volt supply. The regulator <NUM> may include regulatory circuitry operable to provide the <NUM>-volt supply. As another example, the synchronization controller <NUM> may require the <NUM>-volt supply. The regulator <NUM> may include regulatory circuitry operable to provide a <NUM>-volt supply. As another example, the signal conditioner <NUM> may require a <NUM>-volt supply. The regulator <NUM> may include regulatory circuitry operable to provide the <NUM>-volt supply.

The control circuitry <NUM> may provide command and control signals to the switching circuitry <NUM>. The synchronization controller <NUM> may provide synchronization commands such that the driver <NUM> operates according the synchronization commands. As such, the illumination element <NUM> may illuminate according to the illumination of other illumination elements. The timing controller <NUM> may provide timing commands such that the driver <NUM> operates according to the timing commands. As such, the illumination element <NUM> may blink at a predetermined rate. The signal conditioner <NUM> may improve the control signal <NUM> or condition the control signal <NUM>. The control signal <NUM> may be a pulse width modulated signal to the driver <NUM> or driver integrated circuit <NUM>.

The regulator <NUM> may output regulator voltage defined according to the switching circuitry <NUM> or other circuitry on the printed circuit board <NUM>. As an example, the driver <NUM> may require a <NUM>-volt supply. The regulator <NUM> may include regulatory circuitry operable to provide the <NUM>-volt supply. As an example, the driver integrated circuit <NUM> may require a <NUM>-volt supply. The regulator <NUM> may include regulatory circuitry operable to provide the <NUM>-volt supply.

It should be appreciated that any voltage or power regulation circuitry may be used to provide the desired voltages. As a brief, non-limiting example, the regulator <NUM> may be a low-dropout regulator, Zener diode regulator, or another implement. A controller <NUM> may be implemented to provide harvested energy to the monitoring circuitry <NUM>, control circuitry <NUM>, and/or switching circuitry <NUM> on demand. For example, necessary loads may include the control circuitry <NUM>, the monitoring circuitry <NUM>, or portions thereof. The controller <NUM> may operate switches <NUM> or may be operable to open close the switches <NUM> to direct harvested energy as necessary. The switches <NUM> may be operable to disconnect the control circuitry <NUM>, the monitoring circuitry <NUM> or portions thereof based on the energy harvested and stored in the capacitor <NUM>. As an example, coulomb counting or voltage measurements may determine the energy stored in the capacitor <NUM>. The controller <NUM> may disconnect loads that are not necessary for operation of the illumination element <NUM> in response to the energy stored in the capacitor <NUM> falling below a predetermined threshold. As one of many examples, the luminance monitor <NUM> may be disconnected when energy falls below the predetermined threshold.

Referring to <FIG>, a generalized flow diagram <NUM> of the operations that may or may not be performed. It should be appreciated that any of the steps may be omitted, duplicated, rearranged, or performed in parallel. The generalized flow diagram <NUM> includes a determination of charge stored in the capacitor <NUM>. If the charge of the capacitor <NUM> is below a first predetermined threshold, in block <NUM>, the control circuitry <NUM>, or portions thereof, may be disconnected. If the charge of the capacitor <NUM> is below a second predetermined threshold, in block <NUM>, the switching circuitry <NUM> may be disconnected in block <NUM>. The predetermined thresholds may be an energy storage value calculated by one or more controllers <NUM>. Such disconnection may allow normal auxiliary power to provide energization of such circuits. It should be appreciated that disconnection may be based on the voltage supplied by the regulator <NUM>. Higher voltages may be shed before lower voltages are shed.

The controller <NUM> may include any combination of processors, field programmable gate arrays (FPGA), or application specific integrated circuits (ASIC). The controller <NUM> may include memory, volatile and non-volatile, operable to store machine instructions from the processors and other processing mechanisms to receive, calculate, and control devices, as necessary. Machine instructions may be stored (e.g., stored instructions, stored machine instructions, stored steps) in any language or representation, including but not limited to machine code, assembly instructions, C, C++, C#, PYTHON, JAVA, and RUBY. It should be appreciated that any type of wired or wireless configuration is appreciated for any of the communications from the controller <NUM>. Wireless protocols such as ZIGBEE, WI-FI, Near-Field Communications (NFC), BLUETOOTH, or any other implement may be used. Communications may be realized through any protocol or medium known or unknown. Any number of controllers <NUM> may be implemented to individually or collectively provide the necessary operations.

It should be appreciated that voltage and current descriptions herein are merely to describe an example system. Any type of voltage and current may be used to implement the teachings described herein.

The terminology used herein is for the purpose of describing the features associated with the present disclosure and is not intended to be limiting of the present disclosure.

Claim 1:
An aircraft lighting system (<NUM>) disposed in an environment of an aircraft (<NUM>) comprising:
a housing (<NUM>);
an aircraft power system configured to deliver electrical power;
an illumination element (<NUM>) disposed within the housing; and
switching circuitry (<NUM>) including a driver in signal communication with the aircraft power system via a power connection (<NUM>) to receive the electrical power and operable to control illumination of the illumination element using the electrical power, the driver operated with a driver voltage; further comprising
a heatsink (<NUM>) coupled to the illumination element (<NUM>) and thermally conductive thereto;
energy generation circuitry (<NUM>) configured to receive heat from a heatsink, and configured to generate electricity from the environment to generate harvested energy, the electricity generated according to a Seebeck Effect performed by the energy generation circuitry (<NUM>); and
energy harvesting circuitry (<NUM>) including a regulator (<NUM>) configured to draw the harvested energy from the energy generation circuitry (<NUM>), to convert the harvested energy into a regulator voltage and to output the regulator voltage at the driver voltage.