Abstract: A system and method of carrying out a remedial vehicle action in response to determining an error in a monitored vehicle sensor, the method include: determining a vehicle true velocity vector based on measurements from vehicle operations sensors; determining a monitored sensor velocity vector based on measurements from the monitored vehicle sensor; when it is determined that the vehicle true velocity vector is different than the monitored sensor velocity vector, then testing for a first component error, wherein the testing for the first component error includes calculating a first component error value based on a first component measured value and a first component corrected value, and when one or more measured vector components of the monitored sensor velocity vector are determined to be erroneous, them carrying out a remedial vehicle action.

Abstract: A system and method of detecting and responding to a failure of one or more vehicle components, the method including: receiving system input at a failure detection module regarding the one or more vehicle components; determining a system state through use of one or more onboard vehicle sensors; obtaining a nominal state transition matrix and a nominal state input matrix; calculating a present state transition matrix estimate and a present state input matrix estimate based on the nominal state transition matrix, the nominal state input matrix, the system input, and a sampled state derivative; detecting a failure of at least one of the vehicle components based on one or more component parameters of the present state transition matrix estimate and/or the present state input matrix estimate; and performing a vehicle action in response to the detection of the failure.

Abstract: A system and method of detecting and responding to a failure of one or more vehicle components, the method including: receiving system input at a failure detection module regarding the one or more vehicle components; determining a system state through use of one or more onboard vehicle sensors; obtaining a nominal state transition matrix and a nominal state input matrix; calculating a present state transition matrix estimate and a present state input matrix estimate based on the nominal state transition matrix, the nominal state input matrix, the system input, and a sampled state derivative; detecting a failure of at least one of the vehicle components based on one or more component parameters of the present state transition matrix estimate and/or the present state input matrix estimate; and performing a vehicle action in response to the detection of the failure.

Abstract: A system and method of carrying out a remedial vehicle action in response to determining an error in a monitored vehicle sensor, the method include: determining a vehicle true velocity vector based on measurements from vehicle operations sensors; determining a monitored sensor velocity vector based on measurements from the monitored vehicle sensor; when it is determined that the vehicle true velocity vector is different than the monitored sensor velocity vector, then testing for a first component error, wherein the testing for the first component error includes calculating a first component error value based on a first component measured value and a first component corrected value; and when one or more measured vector components of the monitored sensor velocity vector are determined to be erroneous, then carrying out a remedial vehicle action.

Abstract: Improved anti-lock brake systems (ABS) employed on aircraft and land vehicles and methods of operating same employing a sliding mode observer (SMO) incorporated into an ABS algorithm requiring only measurement of wheel speed to regulate the application of braking torque are disclosed. Braking is optimized simply by maintaining an SMO estimate of differential wheel torque (road/tire torque minus applied brake torque) derived from wheel speed at an extremum via applying or releasing the brakes as the extremum is passed through.

Abstract: A refueling drogue adapted to connect to a refueling hose extending from a refueling aircraft. The drogue may include an active stabilization system adapted to effectively stabilize the refueling drogue via control surfaces on the refueling drogue when the refueling drogue is placed in an airstream.

Abstract: A refueling drogue adapted to connect to a refueling hose extending from a refueling aircraft. The drogue may include an active stabilization system adapted to effectively stabilize the refueling drogue via control surfaces on the refueling drogue when the refueling drogue is placed in an airstream.

Abstract: A refueling drogue adapted to connect to a refueling hose extending from a refueling aircraft. The refueling drogue may include an active control system, wherein, in an exemplary embodiment, the active control system is adapted to regulate the position of the drogue to maintain a substantially fixed orientation relative to a refueling aircraft.

Abstract: A refueling drogue adapted to connect to a refueling hose extending from a refueling aircraft. The drogue may include an active stabilization system adapted to effectively stabilize the refueling drogue via control surfaces on the refueling drogue when the refueling drogue is placed in an airstream.

Abstract: A refueling drogue adapted to connect to a refueling hose extending from a refueling aircraft. The refueling drogue may include an active control system, wherein, in an exemplary embodiment, the active control system is adapted to regulate the position of the drogue to maintain a substantially fixed orientation relative to a refueling aircraft.

Abstract: Improved anti-lock brake systems (ABS) employed on aircraft and land vehicles and methods of operating same employing a sliding mode observer (SMO) incorporated into an ABS algorithm requiring only measurement of wheel speed to regulate the application of braking torque are disclosed. Braking is optimized simply by maintaining an SMO estimate of differential wheel torque (road/tire torque minus applied brake torque) derived from wheel speed at an extremum via applying or releasing the brakes as the extremum is passed through.

Abstract: A refueling drogue adapted to connect to a refueling hose extending from a refueling aircraft. The drogue may include a rotatable mass adapted to effectively stabilize the refueling drogue via a gyroscopic effect of the rotating mass on the refueling drogue when the refueling drogue is placed in an airstream.

Abstract: Improved methods and systems for controlling hydraulically or electrically actuated anti-lock brake systems (ABS) on air and land vehicles requiring only measurement of wheel angular speed although brake torque measurements can also be employed if available. A sliding mode observer (SMO) based estimate of net or different wheel torque (road/tire torque minus applied brake torque) derived from the measured wheel speed is compared to a threshold differential wheel torque derived as a function of a “skid signal” also based on wheel speed only to generate a braking control signal. The braking control signal can be employed to rapidly and fully applying and releasing the brakes in a binary on-off manner and, as an additional option, possibly modulating the maximum available brake hydraulic pressure or electrical current when the brakes are in the “on” state in a continuous manner.

Abstract: A method and system for detecting a failure or performance degradation in a dynamic system having sensors for measuring state variables and providing corresponding output signals in response to one or more system input signals are provided. The method includes calculating estimated gains of a filter and selecting an appropriate linear model for processing the output signals based on the input signals. The step of calculating utilizes one or more models of the dynamic system to obtain estimated signals. The method further includes calculating output error residuals based on the output signals and the estimated signals. The method also includes detecting one or more hypothesized failures or performance degradations of a component or subsystem of the dynamic system based on the error residuals.

Abstract: A method and system for detecting a failure or performance degradation in a dynamic system having sensors for measuring state variables and providing corresponding output signals in response to one or more system input signals are provided. The method includes calculating estimated gains of a filter and selecting an appropriate linear model for processing the output signals based on the input signals. The step of calculating utilizes one or more models of the dynamic system to obtain estimated signals. The method further includes calculating output error residuals based on the output signals and the estimated signals. The method also includes detecting one or more hypothesized failures or performance degradations of a component or subsystem of the dynamic system based on the error residuals.

Abstract: A misfire index model-based method and system for detecting misfire in a reciprocating internal combustion engine having an engine cycle frequency in the frequency domain from crankshaft angular velocity. The misfire index model is a function of engine operating condition such as engine load and RPM. Crankshaft angular position is sensed to develop an electrical signal which is a function of the crankshaft angular velocity. The electrical signal contains data which is sampled. The sampled data is transformed to an equivalent frequency domain spectrum including frequency components of the engine cycle frequency and harmonics thereof. A load signal such as mass airflow and an RPM signal are generated. The magnitudes and/or phases of the frequency components and the load and RPM signals are supplied to the misfire index model in an appropriately programmed computer to distinguish between a true misfire and normal cyclic variability which characterizes the combustion process.

Abstract: A trainable, pattern recognition-based method and system for detecting misfire in a reciprocating internal combustion engine having an engine cycle frequency in the frequency domain from crankshaft angular velocity. Preferably, a pattern recognition system including a neural network is utilized. Crankshaft angular position is sensed to develop an electrical signal which is a function of the crankshaft angular velocity. The electrical signal contains data which is sampled. The sampled data is transformed to an equivalent frequency domain spectrum including frequency components of the engine cycle frequency and harmonics thereof. A load signal such as mass airflow and an RPM signal are generated. The magnitudes and phases of the frequency components and the load and RPM signals are supplied to the neural network to distinguish between a true misfire and normal cyclic variability which characterizes the combustion process.

Abstract: Engine misfire is detected in a reciprocating internal combustion engine having an engine cycle frequency in the frequency domain from crankshaft angular velocity. Crankshaft angular position is sensed to develop an electrical signal which is a function of the crankshaft angular velocity. The electrical signal contains data which is sampled. The sampled data is transformed to an equivalent frequency domain spectrum including frequency components of the engine cycle frequency and harmonics thereof. A statistical decision algorithm is applied to the magnitudes of the frequency components to distinguish between a true misfire and normal cyclic variability which characterizes the combustion process. In one embodiment, the misfired cylinder is identified based on the phase of the frequency component at the engine cycle frequency. In another embodiment, the identity of the misfired cylinder is determined by shifting the sampled data prior to transforming the data.

Abstract: A hybrid method and system are disclosed for the detection of internal combustion engine misfires. The method and system are capable of detecting misfires even at very low occurrence rates in real time with inexpensive analog and digital (i.e. hybrid) electronics suitable for use on-board a vehicle, thus satisfying current and proposed exhaust emission control regulations. The method and system exploit a measurement of engine crankshaft angular velocity in conjunction with hybrid electronic signal processing. Once the angular velocity signal is conditioned to minimize the effects of random error and external disturbances, four alternate computationally efficient methods may be used to extract information pertaining to individual cylinder torque productions. Two of the methods employ extremal samples of the estimated torque or velocity waveform to obtain a random torque nonuniformity index or metric.

Abstract: A hybrid method and system are disclosed for the detection of internal combustion engine misfires. The method and system are capable of detecting misfires even at very low occurrence rates in real time with inexpensive analog and digital (i.e. hybrid) electronics suitable for use on-board a vehicle, thus satisfying current and proposed exhaust emission control regulations. The method and system exploit a measurement of engine crankshaft angular velocity in conjunction with hybrid electronic signal processing. Once the angular velocity signal is conditioned to minimize the effects of random error and external disturbances, four alternate computationally efficient methods may be used to extract information pertaining to individual cylinder torque productions. Two of the methods employ extremal samples of the estimated torque or velocity waveform to obtain a random torque nonuniformity index or metric. The other two methods utilize a transformation into the frequency domain.