To provide a controller for internal combustion engine which suppresses that estimation of the combustion state is performed based on the angle information on which the component due to the torsional vibration is superimposed, when the torsional vibration occurs in the crankshaft. A controller for internal combustion engine determines whether a torsional vibration occurs in a crankshaft based on an angle period; calculates a gas pressure torque in burning based on a crank angle acceleration which is calculated based on the angle period; estimates a combustion state of an internal combustion engine based on the gas pressure torque in burning; and stops estimation of the combustion state, when it is determined that the torsional vibration occurred.

A method for sensing damage of bearing of engine using a vibration signal may include separating a vibration signal of an engine sensed by a vibration sensor installed at one side of the engine of a vehicle into a vibration signal by combustion knocking and a vibration signal of a bearing installed between a crank pin and a connecting rod; extracting, by a signal processing filter, a signal of a predetermined natural frequency band from the vibration signal of the bearing; determining whether the vibration signal of the bearing is higher than a predetermined bearing damage threshold, in a predetermined engine state condition in order to sense breakage of the bearing during operation of the engine; and confirming that the bearing has been damaged.

A method for sensing damage of bearing of engine using a vibration signal may include separating a vibration signal of an engine sensed by a vibration sensor installed at one side of the engine of a vehicle into a vibration signal by combustion knocking and a vibration signal of a bearing installed between a crank pin and a connecting rod; extracting, by a signal processing filter, a signal of a predetermined natural frequency band from the vibration signal of the bearing; determining whether the vibration signal of the bearing is higher than a predetermined bearing damage threshold, in a predetermined engine state condition in order to sense breakage of the bearing during operation of the engine; and confirming that the bearing has been damaged.

A method and system for engine monitoring comprises a monitoring device and a remote device that are in communication. The monitoring device is incorporated in or directly attached to the internal combustion engine and functions to sense a characteristic of the internal combustion engine. The monitoring device is configured to transmit data representative of the sensed characteristic to a remote application running on a remote device. The remote device is configure to produce engine monitoring data from the transmitted data using engine characterising data stored on the remote device.

A method and system for engine monitoring comprises a monitoring device and a remote device that are in communication. The monitoring device is incorporated in or directly attached to the internal combustion engine and functions to sense a characteristic of the internal combustion engine. The monitoring device is configured to transmit data representative of the sensed characteristic to a remote application running on a remote device. The remote device is configure to produce engine monitoring data from the transmitted data using engine characterising data stored on the remote device.

Apparatus and associated methods relate to a vibrational sensing system (VSS) including an accelerometer and a data processor, which determines an “operational state” of a mechanical drive unit, the processor further employing the “operational state” to gate learning of long-term vibrational data to exclude collection of non-operational data, the long-term data collected to calculate alarm thresholds. For example, vibrations from a target motor are sensed by a coupled accelerometer. Vibrational data from the accelerometer is fed into a data processor which determines the operational state of the motor. The operational state (e.g., on/off indication) may gate data collection such that data is only acquired during on-time, which may advantageously create accurate baselines from which alarm thresholds may be generated, and nuisance alarms may be avoided.

Conditioning monitoring is provided for rotating components in gearboxes that accounts for gear system dynamics, allowing for improved analysis. A rotation rate for the component is generated from vibration data by estimating the rotation rate based on a tachometer measurement of another shaft and the shaft ratio. This estimated rotation rate is used, together with the known configuration of the component, to estimate a known gear mesh frequency of the component. By filtering for a range of frequencies around the gear mesh frequency based on variation in the shaft rate, the gear mesh frequency can be determined and from that signal, an actual rotation rate for the component can be determined. The actual or determined rotation rate can then be used in deriving an analytic vibration spectrum for the component that is not degraded due to gear system dynamics effects.

Conditioning monitoring is provided for rotating components in gearboxes that accounts for gear system dynamics, allowing for improved analysis. A rotation rate for the component is generated from vibration data by estimating the rotation rate based on a tachometer measurement of another shaft and the shaft ratio. This estimated rotation rate is used, together with the known configuration of the component, to estimate a known gear mesh frequency of the component. By filtering for a range of frequencies around the gear mesh frequency based on variation in the shaft rate, the gear mesh frequency can be determined and from that signal, an actual rotation rate for the component can be determined. The actual or determined rotation rate can then be used in deriving an analytic vibration spectrum for the component that is not degraded due to gear system dynamics effects.

A signal processing method and apparatus quantifies signal “character” in the frequency domain from highly complex signals in a statistically consistent manner. Particular aspects focus on spectral density analyses such as skewness spectral density (SSD), kurtosis spectral density KSD), and probability spectral density (PDSD), among other types of spectral density. Applications of the inventive technique enable not only identification of signal characteristics, but also quantification of signal behavior in an explainable way. Higher orders of spectral densities are 1) physical and statistical, 2) convergent with boundable error, 3) integrable and relatable to the time-domain, and 4) typically differentiable.

A vibration measurement sensor (3) adapted to measure the vibrations formed on a test object (O) with moving mechanical systems, at least one noise measurement sensor (4) adapted to measure sound intensity and/or particle velocity and/or sound pressure in at least one direction, i.e. on one axis, and a vibration and noise mapping system (1) that is adapted to control the vibration measurement sensor (3) and the noise measurement sensor (4), to provide the vibration and acoustic performance data of the test object (O) according to the data obtained from these units (3, 4) and to identify the areas on the test object (O) that are problematic or need to be studied further in order to improve vibration and acoustic performances thereof, and to control the operation of test objects (O) such as moving mechanical systems under different conditions.