Abstract: Methods and systems for calibrating an engine having a rotating shaft are provided. Readings from a plurality of speed sensors provided in one of a plurality of configurations about the shaft are obtained over a plurality of rotations of the shaft, the readings indicative of the passage of position markers and associated with a first precision level. A parameter indicative of relative spacing between the plurality of speed sensors is determined by applying a statistical algorithm to the readings, the parameter being associated with a second precision level higher than the first precision level. The parameter is compared to reference parameters associated with the plurality of configurations to identify an actual speed sensor configuration from amongst the plurality of configurations. The engine is calibrated based on the actual speed sensor configuration.

Abstract: Methods and systems for operating an on-off valve coupled to a system for regulating a system parameter are described herein. The method comprises setting an upper limit on a duty cycle of a pulse width modulation (PWM) signal for controlling the valve, generating the PWM signal with the duty cycle less than or equal to the upper limit and applying the PWM signal to the valve, monitoring the system parameter as the PWM signal is applied, and increasing the upper limit on the duty cycle over time until the system parameter reaches a target.

Abstract: Method and system for controlling engine speed in a multi-engine aircraft, comprising monitoring a request for a first engine and a second engine to generate a given thrust and determining a corresponding engine speed for the first engine and the second engine in accordance with the given thrust. When the corresponding engine speed is outside of a selected speed range, a first engine speed and a second engine speed are allowed to track the corresponding engine speed. When the corresponding engine speed is within the selected speed range, a transition of the first engine speed and the second engine speed through the selected speed range is staggered by allowing one of the first engine speed and the second engine speed to transition through the selected speed range while holding the other of the first engine speed and the second engine speed outside of the selected speed range.

Abstract: Methods and systems for calibrating an engine having a rotating shaft are provided. Readings from a plurality of speed sensors provided in one of a plurality of configurations about the shaft are obtained over a plurality of rotations of the shaft, the readings indicative of the passage of position markers and associated with a first precision level. A parameter indicative of relative spacing between the plurality of speed sensors is determined by applying a statistical algorithm to the readings, the parameter being associated with a second precision level higher than the first precision level. The parameter is compared to reference parameters associated with the plurality of configurations to identify an actual speed sensor configuration from amongst the plurality of configurations. The engine is calibrated based on the actual speed sensor configuration.

Abstract: Methods and systems for operating an on-off valve coupled to a system for regulating a system parameter are described herein. The method comprises setting an upper limit on a duty cycle of a pulse width modulation (PWM) signal for controlling the valve, generating the PWM signal with the duty cycle less than or equal to the upper limit and applying the PWM signal to the valve, monitoring the system parameter as the PWM signal is applied, and increasing the upper limit on the duty cycle over time until the system parameter reaches a target.

Abstract: Systems and methods for controlling thrust of an engine for an aircraft are described herein. A position of a thrust lever for controlling the engine is obtained from one or more sensors. Air data is obtained from one or more air data inputs. An air temperature data input is detected as compromised from the air data. In response to detecting the air temperature data input is compromised, a target engine rotational speed is determined based on the position of the thrust lever and at least one of altitude data and Mach number data from the air data. A rotational speed of the engine is adjusted to the target engine rotational speed to control thrust of the engine.

Abstract: Method and system for controlling engine speed in a multi-engine aircraft, comprising monitoring a request for a first engine and a second engine to generate a given thrust and determining a corresponding engine speed for the first engine and the second engine in accordance with the given thrust. When the corresponding engine speed is outside of a selected speed range, a first engine speed and a second engine speed are allowed to track the corresponding engine speed. When the corresponding engine speed is within the selected speed range, a transition of the first engine speed and the second engine speed through the selected speed range is staggered by allowing one of the first engine speed and the second engine speed to transition through the selected speed range while holding the other of the first engine speed and the second engine speed outside of the selected speed range.

Abstract: A system and method for rotor bow mitigation for a gas turbine engine are provided. An elapsed time since a shutdown of the engine and an idle operation time of the engine prior to the shutdown are determined. A rotor bow mitigation period is determined based on the elapsed time and the idle operation time and, prior to initiating a start sequence of the engine, the engine is motored for a duration of the rotor bow mitigation period.

Abstract: A system and method for rotor bow mitigation for a gas turbine engine are provided. An elapsed time since a shutdown of the engine and an idle operation time of the engine prior to the shutdown are determined. A rotor bow mitigation period is determined based on the elapsed time and the idle operation time and, prior to initiating a start sequence of the engine, the engine is motored for a duration of the rotor bow mitigation period.

Abstract: Systems and methods for controlling thrust of an engine for an aircraft are described herein. A position of a thrust lever for controlling the engine is obtained from one or more sensors. Air data is obtained from one or more air data inputs. An air temperature data input is detected as compromised from the air data. In response to detecting the air temperature data input is compromised, a target engine rotational speed is determined based on the position of the thrust lever and at least one of altitude data and Mach number data from the air data. A rotational speed of the engine is adjusted to the target engine rotational speed to control thrust of the engine.

Abstract: The presently disclosed technology teaches using a tilt-sensitive virtual marking implement to render an impression on an electronic presentation device. Further, a bearing measurement and a tilt measurement of the virtual marking implement are made with respect to the surface. The tilt and bearing are then used to vary geometry of an impression profile associated with the physical marking implement as well as an intensity of the rendering. A user may actively vary the impression profile while he or she produces strokes of the virtual marking implement across the surface without changing the physical marking implement selection or switching to a different virtual marking implement. When creating a rendering on a virtual canvas using the virtual marking implement and the surface, a user may wish to vary an orientation of the virtual marking implement so that a corresponding impression profile mimics an impression of a selected physical marking implement.

Abstract: The presently disclosed technology teaches using a tilt-sensitive virtual marking implement to render an impression on an electronic presentation device. Further, a bearing measurement and a tilt measurement of the virtual marking implement are made with respect to the surface. The tilt and bearing are then used to vary geometry of an impression profile associated with the physical marking implement as well as an intensity of the rendering. A user may actively vary the impression profile while he or she produces strokes of the virtual marking implement across the surface without changing the physical marking implement selection or switching to a different virtual marking implement. When creating a rendering on a virtual canvas using the virtual marking implement and the surface, a user may wish to vary an orientation of the virtual marking implement so that a corresponding impression profile mimics an impression of a selected physical marking implement.

Abstract: The presently disclosed technology teaches using a tilt-sensitive virtual marking implement to render an impression on an electronic presentation device. Further, a bearing measurement and a tilt measurement of the virtual marking implement are made with respect to the surface. The tilt and bearing are then used to vary geometry of an impression profile associated with the physical marking implement as well as an intensity of the rendering. A user may actively vary the impression profile while he or she produces strokes of the virtual marking implement across the surface without changing the physical marking implement selection or switching to a different virtual marking implement. When creating a rendering on a virtual canvas using the virtual marking implement and the surface, a user may wish to vary an orientation of the virtual marking implement so that a corresponding impression profile mimics an impression of a selected physical marking implement.

Abstract: A method of determining a tilt, bearing, and/or barrel rotation of a virtual marking implement with respect to a surface is disclosed herein. The tilt, bearing, and/or barrel rotation are used to vary geometry of an impression profile associated with a selected physical marking implement as well as the intensity of a rendering on an electronic presentation device. Further, the impression profile associated with the selected physical marking implement may change over time as marks are rendered on the electronic presentation device. More specifically, a quantity of use of the physical marking implement defines in part the size, orientation, and/or shape of one or more facets on the physical marking implement. Existing facets on the physical marking implement may be modified and/or new facets may be added to the physical marking implement as marks are rendered on the electronic presentation device.