Abstract: A system for measuring in-cylinder parameters utilizing an image charge measured in an engine cylinder by an in-cylinder pressure sensor due to chemi and or thermal ionization in Engine. The in-cylinder pressure sensor includes a sensing element, which is a metal sensor probe with a selective coating (e.g., metal, oxides of metal, native oxides, semiconductor, oxides of semiconductors, ceramics, glass, dielectric, etc., in the form of a coating on the metallic probe, tube, etc) in order to function in harsh, corrosive and/or elevated temperature environments. The output of the sensor can be connected to a signal-conditioning unit, which includes a low noise differential charge amplifier with an auto offset correction circuit to measure fast varying signals. The signal out from the conditioning unit can be acquired utilizing a high-speed microcontroller-based data acquisition system with suitable software to analyze and estimate parameters such as, for example, in cylinder pressure and knocking.

Abstract: A system for measuring in-cylinder parameters utilizing an image charge measured in an engine cylinder by an in-cylinder pressure sensor due to chemi and or thermal ionization in Engine. The in-cylinder pressure sensor includes a sensing element, which is a metal sensor probe with a selective coating (e.g., metal, oxides of metal, native oxides, semiconductor, oxides of semiconductors, ceramics, glass, dielectric, etc., in the form of a coating on the metallic probe, tube, etc) in order to function in harsh, corrosive and/or elevated temperature environments. The output of the sensor can be connected to a signal-conditioning unit, which includes a low noise differential charge amplifier with an auto offset correction circuit to measure fast varying signals. The signal out from the conditioning unit can be acquired utilizing a high-speed microcontroller-based data acquisition system with suitable software to analyze and estimate parameters such as, for example, in cylinder pressure and knocking.

Abstract: A low noise differential charge amplifier circuit for measuring discrete (e.g., pico coulomb) charges in noisy, elevated temperature and corrosive environments. An input stage of a differential charge amplifier circuit includes a twisted and or untwisted two pair cable with a grounded shield. One twisted and or untwisted pair can be connected to a sensor and a first charge amplifier and a second twisted and or/untwisted pair can be connected to a sensor electrical equivalent impedance circuit and or kept open and a second charge amplifier. The output from the charge amplifiers can be directed to a differential amplifier in order to provide an amplified sensor signal without external noise signal mainly from power supply mains. The differential amplifier and the charge amplifiers can include an auto offset correction circuit to reduce errors due to offsets.

Abstract: A single cell oxygen sensor apparatus and method are disclosed. An yttrium-based stabilized layer having electrical terminals connected to the yttrium-based stabilized layer can be provided on a substrate, wherein the yttrium-based stabilized layer is excitable by a constant current applied to the electrical terminals. A plurality of electrodes are located on a side of the yttrium-based stabilized layer and a plurality of heater elements located on said substrate opposite said yttrium-based stabilized layer. The heater elements can maintain the yttrium-based stabilized layer at a particular temperature. A cavity is formed and located between the yttrium-based stabilized layer and the heater elements. The partial pressure of oxygen can be measured by comparing the partial pressure of oxygen within the cavity with respect to the partial pressure of oxygen in the atmosphere external to the single cell oxygen sensor apparatus.