Abstract: Systems and methods for detecting wheel speed are provided. An electric circuit for detecting a speed of a wheel may comprise: a transducer in electronic communication with an operational amplifier (OP-AMP), the transducer configured to output a variable signal in response to an angular velocity of a rotatable member of a wheel assembly; a constant voltage source in electronic communication with the OP-AMP; and a sensor in electronic communication with an output terminal of the OP-AMP configured to monitor an output signal of the OP-AMP, the output signal including a period; and a controller configured to receive the output signal and configured to calculate the speed of the wheel according to a pre-determined ratio of the wheel speed and the period. In various embodiments, the circuit may allow for slow wheel speed detection.

Abstract: Braking control systems, such as for an aircraft, use a hydraulic failure isolation valve intermediate an accumulator power source and a dual valve assembly for mechanical operation when a hydraulic power source experiences a disruption.

Abstract: An emergency braking monitoring system includes a wheel assembly having a first wheel, an emergency braking monitoring unit coupled to the wheel assembly, and a locked wheel annunciation center coupled to the emergency braking monitoring unit for annunciation purposes. The emergency braking monitoring unit generates a fault annunciation signal based on a determination as to whether a first wheel speed value originating from the first wheel of the wheel assembly is a predetermined amount less than a reference value for a persistence time.

Abstract: Braking control systems, such as for an aircraft, use a hydraulic failure isolation valve intermediate an accumulator power source and a dual valve assembly for mechanical operation when a hydraulic power source experiences a disruption.

Abstract: An emergency braking monitoring system includes a wheel assembly having a first wheel, an emergency braking monitoring unit coupled to the wheel assembly, and a locked wheel annunciation center coupled to the emergency braking monitoring unit for annunciation purposes. The emergency braking monitoring unit generates a fault annunciation signal based on a determination as to whether a first wheel speed value originating from the first wheel of the wheel assembly is a predetermined amount less than a reference value for a persistence time.

Abstract: A controller unit for an aircraft control system may include a circuit board and a positive temperature coefficient device. The circuit board may include conductive traces and a plurality of mounted electronic components forming a circuit. The positive temperature coefficient device may be configured to provide overcurrent protection for the circuit. The controller unit may be located in explosion-restricted areas of the aircraft.

Abstract: Systems and methods for detecting circuit conditions are provided. A method for detecting a condition of a circuit may comprise: applying electrical energy to at least a circuit element in the circuit, a level of the electrical energy being insufficient to fully actuate the circuit element. The method may further comprise verifying integrity of the circuit.

Abstract: Systems and methods for detecting circuit conditions are provided. A method for detecting a condition of a circuit may comprise: applying electrical energy to at least a circuit element in the circuit, a level of the electrical energy being insufficient to fully actuate the circuit element. The method may further comprise verifying integrity of the circuit.

Abstract: Systems and methods for detecting wheel speed are provided. An electric circuit for detecting a speed of a wheel may comprise: a transducer in electronic communication with an operational amplifier (OP-AMP), the transducer configured to output a variable signal in response to an angular velocity of a rotatable member of a wheel assembly; a constant voltage source in electronic communication with the OP-AMP; and a sensor in electronic communication with an output terminal of the OP-AMP configured to monitor an output signal of the OP-AMP, the output signal including a period; and a controller configured to receive the output signal and configured to calculate the speed of the wheel according to a pre-determined ratio of the wheel speed and the period. In various embodiments, the circuit may allow for slow wheel speed detection.

Abstract: An aircraft brake system may include a linear variable differential transformer (“LVDT”). A brake control unit (“BCU”) may measure an output voltage from the LVDT. The BCU may include a hardware module, a software module, and an offset module. The hardware module may include a preprogrammed threshold voltage. The output voltage may be measured, and an offset voltage may be determined and stored in the offset module. The software module may measure the sum of the output voltage and the offset voltage. In response to the hardware module and the software module indicating that the threshold voltage has been reached, the BCU may allow braking of the aircraft.

Abstract: An aircraft brake system may include a linear variable differential transformer (“LVDT”). A brake control unit (“BCU”) may measure an output voltage from the LVDT. The BCU may include a hardware module, a software module, and an offset module. The hardware module may include a preprogrammed threshold voltage. The output voltage may be measured, and an offset voltage may be determined and stored in the offset module. The software module may measure the sum of the output voltage and the offset voltage. In response to the hardware module and the software module indicating that the threshold voltage has been reached, the BCU may allow braking of the aircraft.