Heinz Eisenschmid

An automotive engine oil viscosity sensor

For the evaluation of the condition of automotive engine oil, the oils viscosity is one of the most important parameters. Using microacoustic viscosity sensors, an oil-viscosity measurement can be performed on-board. In this contribution, we discuss the behavior of the viscosity of engine oil, its temperature dependence, and the resulting representation in terms of output signals of microacoustic viscosity sensors. These considerations are illustrated by means of measurement results obtained for used oil samples, which have been obtained from test cars and fresh oil samples out of different viscosity classes. Finally, the detection of the viscosity increase due to soot contamination is demonstrated.

The potential of microacoustic SAW- and BAW-based sensors for automotive applications - a review

In recent years, sensors and sensor systems have gained increasing importance for automotive electronics. In this paper, the suitability and the perspectives in the application of microacoustic surface- and bulk-acoustic-wave sensors in the fields of angular rate sensors, pressure sensors, wireless sensor readout, and liquid sensors are discussed.

Microacoustic viscosity sensor for automotive applications

For the evaluation of the condition of automotive engine oil, the oils viscosity is an important parameter. Using microacoustic viscosity sensors, an oil viscosity measurement can be performed on-board. In this contribution we outline the basic requirements and review the suitability of microacoustic sensors for this application.