Sensing system and method
A system includes one or more processors and a resonant sensor that contacts oil within an engine of a vehicle system. The sensor generates electrical stimuli at different times during an operational life of the engine. Each electrical stimulus has multiple different frequencies applied to the oil. The one or more processors receive electrical signals representing impedance responses of the oil to the electrical stimuli. The one or more processors determine a concentration of a polar analyte in the oil at the different times based on the impedance responses and calculate a degradation value for the engine based on the polar analyte concentration. Responsive to the degradation value exceeding a designated degradation threshold, the one or more processors at least one of schedule maintenance for the vehicle system, provide an alert to schedule maintenance for the vehicle system, or prohibit operation of the vehicle system until maintenance is performed.
1. A system comprising:
a resonant sensor configured to be in contact with oil within an engine of a vehicle system, the sensor including electrodes and a sensing region circuit that is configured to generate electrical stimuli at different times during an operational life of the engine, each electrical stimulus having multiple different frequencies that are applied to the oil via the electrodes; and
one or more processors configured to receive multiple electrical signals from the resonant sensor, the electrical signals representative of impedance responses of the oil to the electrical stimuli, the one or more processors configured to analyze the impedance responses and determine a concentration of a polar analyte in the oil at each of the different times based on the impedance responses, the one or more processors further configured to calculate a degradation value for the engine based on the concentration of the polar analyte in the oil,
wherein, responsive to the degradation value exceeding a designated degradation threshold, the one or more processors are configured to at least one of schedule maintenance for the vehicle system, provide an alert to schedule maintenance for the vehicle system, or prohibit operation of the vehicle system until maintenance is performed on the vehicle system,
further wherein the one or more processors are configured to calculate the degradation value as an integral of the concentration of the polar analyte in the oil over a time period in which the electrical stimuli are applied to the oil.
2. The system of claim 1 , wherein the resonant sensor is a multivariable sensor.
3. The system of claim 1 , wherein the resonant sensor individually quantifies a concentration of at least one contaminant in the oil and a level of aging of the oil.
4. The system of claim 1 , wherein the resonant sensor individually quantifies a concentration of molecularly dissolved water and a concentration of dispersed water in the oil.
5. The system of claim 1 , wherein the polar analyte in ore oil is at least one of an acidic component or water.
6. The system of claim 1 , wherein the polar analyte in the oil is water, the system further comprising a temperature sensor configured to monitor a temperature within the engine, the one or more processors configured to calculate the degradation value for the engine based on the concentration of water in the oil during time periods that the temperature within the engine is less than an evaporation threshold temperature.
7. The system of claim 1 , wherein the polar analyte in the oil is water, the system further comprising a vibration sensor mounted to the vehicle system, the vibration sensor configured to detect the engine is in a non-operating state based on an amount of vibration of the vehicle system, the one or more processors configured to calculate the degradation value for the engine based on the concentration of water in the oil during time periods that the engine is in the non-operating state.
8. The system of claim 1 , wherein the resonant sensor is configured to generate the electrical stimuli periodically at intervals no greater than five minutes in duration in order for the one or more processors to periodically determine the concentration of the polar analyte in the oil during the operational life of the engine.
9. The system of claim 1 , wherein the one or more processors are configured to analyze the impedance response by extracting resonance parameters of the impedance response, the resonance parameters including one or more of a frequency position (Fp) and magnitude (Zp) of a real part of the impedance response, a resonant frequency (F 1 ) and antiresonant frequency (F 2 ) of an imaginary part of the impedance response, an impedance magnitude (Z 1 ) at the resonant frequency (F 1 ) and an impedance magnitude (Z 2 ) at the antiresonant frequency (F 2 ), and a zero-reactance frequency (Fz) at the imaginary part of the impedance response.
10. The system of claim 1 , wherein the sensing region circuit of the resonant sensor includes at least one inductor-capacitor-resistor (LCR) resonant circuit.
11. A system, comprising:
a resonant sensor configured to be in contact with oil within an engine of a vehicle system, the sensor including electrodes and a sensing region circuit that is configured to generate electrical stimuli at different times during an operational life of the engine, each electrical stimulus having multiple different frequencies that are applied to the oil via the electrodes; and
one or more processors configured to receive multiple electrical signals from the resonant sensor, the electrical signals representative of impedance responses of the oil to the electrical stimuli, the one or more processors configured to analyze the impedance responses and determine a concentration of a polar analyte in the oil at each of the different times based on the impedance responses, the one or more processors further configured to calculate a degradation value for the engine based on the concentration of the polar analyte in the oil,
wherein, responsive to the degradation value exceeding a designated degradation threshold, the one or more processors are configured to at least one of schedule maintenance for the vehicle system, provide an alert to schedule maintenance for the vehicle system, or prohibit operation of the vehicle system until maintenance is performed on the vehicle system, wherein the one or more processors are further configured to estimate an amount of time remaining in the operational life of the engine based on the degradation value for the engine, the remaining amount of time inversely proportional to the degradation value.
12. A method comprising:
obtaining multiple measurements of a concentration of at least one polar analyte in oil within an engine of a vehicle system, the measurements obtained at different times during an operational life of the engine via a resonant sensor in operational contact with the oil, the resonant sensor including electrodes and a sensing region circuit that is configured to generate an electrical stimulus having multiple different frequencies that are applied to the oil via the electrodes, the concentration of the at least one polar analyte in the oil determined based on an impedance response of the oil to the electrical stimulus;
calculating a degradation value for the engine based on the concentration of the at least one polar analyte in the oil within the engine; and
responsive to the degradation value exceeding a designated degradation threshold, at least one of scheduling maintenance for the vehicle system, providing an alert to schedule maintenance for the vehicle system, or prohibiting operation of the vehicle system until maintenance is performed on the vehicle system,
further wherein the degradation value is calculated as an integral of the concentration of the at least one polar analyte in the oil over a time period that the measurements of the concentration are obtained.
13. The method of claim 12 , wherein the measurements of the concentration of the at least one polar analyte in the oil are obtained periodically at intervals no greater than five minutes in duration.
14. The method of claim 12 , further comprising detecting that the engine is in a non-operating state, wherein at least some of the measurements of the concentration of the at least one polar analyte in oil are obtained while the engine is in the non-operating state.
15. The method of claim 12 , wherein the designated degradation threshold is a first degradation threshold and responsive to the degradation value exceeding the first degradation threshold, the method includes at least one of scheduling replacement of the oil within the engine or providing an alert to schedule replacement of the oil within the engine.
16. The method of claim 15 , wherein, responsive to the degradation value exceeding a second degradation threshold that is greater than the first degradation threshold, the method includes at least one of scheduling servicing of the engine or providing an alert to schedule servicing of the engine.
17. The method of claim 12 , wherein the at least one polar analyte in the oil that is measured is at least one of an acidic component or water.
18. The method of claim 12 , wherein the at least one polar analyte that is measured is water and the method further comprises monitoring a temperature of the oil within the engine, the degradation value for the engine calculated based on measurements of the concentration of water in the oil that are obtained during time periods that the temperature of the oil is less than an evaporation threshold temperature.
19. A method comprising:
obtaining multiple measurements of a concentration of at least one polar analyte in oil within an engine of a vehicle system, the measurements obtained at different times during an operational life of the engine via a resonant sensor in operational contact with the oil, the resonant sensor including electrodes and a sensing region circuit that is configured to generate an electrical stimulus having multiple different frequencies that are applied to the oil via the electrodes, the concentration of the at least one polar analyte in the oil determined based on an impedance response of the oil to the electrical stimulus;
calculating a degradation value for the engine based on the concentration of the at least one polar analyte in the oil within the engine; and
responsive to the degradation value exceeding a designated degradation threshold, at least one of scheduling maintenance for the vehicle system, providing an alert to schedule maintenance for the vehicle system, or prohibiting operation of the vehicle system until maintenance is performed on the vehicle system, further comprising estimating an amount of time remaining in the operational life of the engine based on the degradation value for the engine, the remaining amount of time inversely proportional to the degradation value.