An emergency park brake system of an aircraft may include an electrical power interface, an electromechanical actuator, and a hydraulic brake valve. The electrical power interface may be configured to receive electrical power from a power source. The electromechanical actuator may be in selective power receiving communication with the electrical power interface and the electromechanical actuator may be mechanically coupled to and configured to selectively actuate the hydraulic brake valve. The electrical connection between the electromechanical actuator and the electrical power interface may be based on an emergency braking input.

The invention relates to a method for controlling an aircraft taxi system, comprising the steps of: generating a traction command (Com) to control an electric motor of a wheel drive actuator; detecting whether or not an external brake command, intended to control braking of the wheel via the brake, is generated; if an external braking command is generated, producing a predetermined minimum command (Cmp) to control the electric motor so that the drive actuator applies a strictly positive predetermined minimum motor torque to the wheel during braking; detecting whether a speed of the aircraft becomes zero and, if so, inhibiting the predetermined minimum command (Cmp) so that the drive actuator applies zero torque to the wheel.

The invention provides methods and systems for controlling speed of an aircraft during an autonomous pushback maneuver, i.e. under the aircraft's own power without a pushback tractor. The method includes applying a torque to at least one landing gear wheel of the aircraft, the torque being in a direction opposite to the backwards rolling direction of rotation of the landing gear wheel. The torque applied does not exceed a limit for ensuring aircraft longitudinal stability. For longitudinal stability the torque applied should not cause the aircraft to risk a tip-over event.

An aircraft landing gear longitudinal force control system for an aircraft having landing gears with braking and/or driving wheel(s). The system includes an error-based force controller having feedback for minimising any error between the demanded force and the actual force achieved by the force control system. The feedback may be derived from force sensors on the landing gear for direct measurement of the landing gear longitudinal force. The force control system may include an aircraft level landing gear total force controller and/or a landing gear level force controller for each actuated landing gear.

A landing gear assembly may include a first wheel and a second wheel, a first wheel sensor coupled to the first wheel and a second wheel sensor coupled to the second wheel, and a controller coupled to the first wheel sensor and the second wheel sensor. A tangible, non-transitory memory may have instructions for detecting a dragging brake. The controller may perform operations including receiving data from the first wheel sensor and the second wheel sensor, calculating a wheel speed characteristic for each of the first wheel and the second wheel based on the data, identifying a lowest value for the wheel speed characteristic, determining a moving average for the wheel speed characteristic, comparing the lowest value to the moving average, and whether the lowest value for the wheel speed characteristic indicates a dragging brake.

An electric brake power conversion and distribution system for use in aircraft is provided. An array of DC-DC converters is interposed between a DC power source and a plurality of aircraft electric brake actuators. Each of the DC-DC converters has a characteristic output voltage. The DC-DC converters are interconnected in an additive series of connections to provide an output voltage to the plurality of aircraft electric brake actuators that comprises the sum of the characteristic voltages of the DC-DC converters that are enabled at a particular point in time. A controller manipulates an array of switches interconnected with the array of DC-DC converts, such that the controller can selectively enable or inhibit selected ones of the DC-DC converters, as desired. Accordingly different voltages can be made available for the electric brake actuators depending upon aircraft activity, such as landing, taxiing, parking, or in flight. The invention reduces the size, weight, cost, and associated heat buildup of prior power conversion and distribution systems.

A method of controlling an aircraft electrical taxiing system, the method comprising the steps of: defining a target value (Ld_nmax) for an electrical parameter; generating a nominal force command (Cmd_nom) for the electrical taxiing system; in parallel with generating the nominal force command (Cmd_nom), using a processing system (2) to produce a maximum command force (Force_max) for the electrical taxiing system so that a real value of the electrical parameter reaches the target value (Ld_nmax), the processing system (2) comprising a regulator loop (4); and generating an optimized force command (Cmd_opt) for the electrical taxiing system equal to the smaller of the nominal force command and the maximum command force.

A method for detecting an erroneous velocity data using a controller in communication with a velocity sensor onboard a vehicle includes receiving a time-series velocity data from the velocity sensor, calculating a time-series acceleration data using the time-series velocity data, calculating a time-series jerk data using the time-series acceleration data, calculating a saturated (numerically bounded) jerk data using the time-series jerk data, calculating an estimated acceleration data using the saturated jerk data, calculating a difference between the estimated acceleration data and the time-series acceleration data, and determining whether the difference is greater than a threshold value. The erroneous velocity data is detected in response to the difference being greater than the threshold value.

Systems and methods are disclosed for predicting a hot spot. One method comprises receiving, by a hot spot prediction system, vehicle characteristics associated with a vehicle and traffic data. Then the hot spot prediction system determines a hot spot and an estimated arrival time at the hot spot based on the vehicle characteristics and the traffic data. Following the determination, an auto brake application system receives the hot spot and the estimated arrival time and determines a safe stop time based on the vehicle characteristics, the hot spot and the estimated arrival time. The auto brake application system then sends a notification to the vehicle based on determining that the vehicle can stop within the safe stop time, and performs an action in response to receiving a confirmation from the vehicle.

A brake control system of the present disclosure calibrates a servo valve and calculates a calibrated transfer function associated with the servo valve for precise braking in open-loop mode. The calibration steps may include determining i) whether an aircraft is on a ground surface, ii) whether the aircraft is not moving relative to the ground surface, and iii) whether braking is applied to a brake system of the aircraft. The brake control unit may calibrate the servo valve in response to the brake control unit determining that i) the aircraft is on the ground surface, ii) the aircraft is not moving relative to the ground surface, and iii) the braking is not applied to the brake system of the aircraft. The calibration process includes sending two or more test currents to the servo valve, and determining braking pressures associated with those test currents to calculate the transfer function.