Deconvolution method of resonance detection and removal from crankshaft speed measurements
First Claim
1. A method of resonance detection and removal from crankshaft speed measurements comprising:
- measuring a crankshaft speed;
converting said measured crankshaft speed into an input signal;
sending said input signal to an engine controller;
determining an impulse response of a resonance system from said input signal;
subjecting said input signal to a deconvolution operation utilizing said impulse response of said resonance system; and
obtaining an output signal representative of an engine performance characteristic from said deconvolution operation.
22 Assignments
0 Petitions
Accused Products
Abstract
The present invention provides a system for detecting and removing resonance from crankshaft speed measurements comprising signal demodulation and deconvolution processing. According to the invention, a crankshaft speed sensor sends an appropriate signal corresponding to crankshaft speed to an engine controller. The input signal with resonance noise is subjected to a demodulation operation in N demodulation subsystems for resonance detection and identification. Also, the input signal with resonance noise is subjected to a deconvolution operation in N deconvolution subsystems for resonance noise removal. The demodulated signals are compared to a given set of criteria for selecting a desired signal subsystem. The desired demodulated signal subsystem is then used to screen the deconvolved signal so that only a matching deconvolved signal exits the system as the system output. Accordingly, the signal from a deconvolved signal subsystem matching the selected demodulated signal subsystem is selected as the system output. By properly identifying the desired signal subsystem during demodulation and suppressing resonance noise during deconvolution, the system output signal has an enhanced signal-to-noise ratio. Hence, the output signal is better suited for further processing, such as engine misfire detection, than according to the prior art.
18 Citations
11 Claims
-
1. A method of resonance detection and removal from crankshaft speed measurements comprising:
-
measuring a crankshaft speed; converting said measured crankshaft speed into an input signal; sending said input signal to an engine controller; determining an impulse response of a resonance system from said input signal; subjecting said input signal to a deconvolution operation utilizing said impulse response of said resonance system; and obtaining an output signal representative of an engine performance characteristic from said deconvolution operation. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A method of detecting and removing resonance from crankshaft speed measurements comprising:
-
measuring a crankshaft speed; converting said measured crankshaft speed into a crankshaft speed measurement input signal; sending said input signal to an engine controller; subjecting said input signal to a demodulation operation to detect and identify a plurality of demodulated signals, said demodulation operation including comparing resonances of said input signal to a set of known resonances; subjecting said input signal to a deconvolution operation to obtain a plurality of deconvolved signals from said input signal in which resonance interference is effectively suppressed; and selecting a desired signal from said deconvolution operation as an output signal according to said plurality of demodulated signals from said demodulation operation, said output signal representing engine misfire detection. - View Dependent Claims (7, 8, 9)
-
-
10. A method of detecting and removing resonance from crankshaft speed measurements comprising:
-
generating an input signal from a detected crankshaft speed measurement; filtering said input signal in predetermined ranges; subjecting said input signal to a demodulation operation for detecting and identifying a plurality of demodulated signals including a set of input signal resonances; removing predetermined demodulated signals from said input signal; generating a first level output signal from said plurality of demodulated signals detected and identified in said demodulation operation by comparing said set of input signal resonances to known criteria, said criteria including inhibitor signals; subjecting said input signal to a deconvolution operation to obtain a plurality of deconvolved signals in which resonance interference is effectively suppressed; and selecting a desired signal from said plurality of deconvolved signals as an output signal according to said first level output signal. - View Dependent Claims (11)
-
Specification