This paper focuses on the primary automotive sensor technologies used today and their related system applications. This paper describes new automotive sensors that measure position, pressure, torque, exhaust temperature, angular rate, engine oil quality, flexible fuel composition, long-range distance, short-range distance, and ambient gas concentrations. In addition, new features are described for sensors that measure linear acceleration, exhaust oxygen, comfort/convenience factors, and night vision. New automotive system applications are described for sensors that measure speed/timing, mass air flow, and occupant safety/security.

New Automotive Sensors—A Review

Lubricating oil conditioning sensors for online machine health monitoring – A review

There is an increasing demand for the on-line condition monitoring of lubricating oils. In our recent research, we considered various sensor principles for the on-line monitoring of thermal aging of engine oils. One of the investigated parameters is the viscosity of the lubricating oil, which can be efficiently measured using microacoustic sensors. Compared to conventional viscometers, these sensors probe a different rheological domain, which needs to be considered in the interpretation of the measurement results. This specific behavior is examined by systematically investigating engine oils with and without additive packages, which were subjected to a defined artificial aging process.

Viscosity sensors for engine oil condition monitoring—Application and interpretation of results

This paper reviews our recent work on vibrating sensors for the physical properties of fluids, particularly viscosity and density. Several device designs and the associated properties, specifically with respect to the sensed rheological domain and the onset of non-Newtonian behavior, are discussed.

Miniaturized sensors for the viscosity and density of liquids-performance and issues

For the evaluation of the condition of automotive engine oil, the oil's 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.

An automotive engine oil viscosity sensor

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.

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

Monitoring the engine oil condition in automobiles yields increased oil drain intervals adapted to the actual state of the engine oil. This yields both, ecological as well as economical advantages. Furthermore the engine oil condition provides insight into the actual state of the engine and thus supports the early detection of possible engine failures. In this contribution we present a multifunctional oil condition sensor determined for the inclusion in an engine oil monitoring system.

A Novel Multifunctional Oil Condition Sensor

For the evaluation of the condition of automotive engine oil, the oil's 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.

Microacoustic viscosity sensor for automotive applications

Die Überwachung des Motorölzustandes in Kraftfahrzeugen erlaubt die Realisierung vergrößerter Ölwechselintervalle. Dies bringt sowohl ökonomische als auch ökologische Vorteile. Überdies kann man durch die direkte Überwachung des Ölzustandes Rückschlüsse auf den momentanen Zustand des Motors ziehen, was die frühzeitige Erkennung von möglichen Motorschäden unterstützt. In diesem Beitrag präsentieren wir einen multifunktionalen Ölzustandssensor, welcher sich für als Geber in einem Motorölmanagementsystem eignet.

H. Eisenschmid

Papers

An automotive engine oil viscosity sensor

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

A Novel Multifunctional Oil Condition Sensor

Microacoustic viscosity sensor for automotive applications

Multifunktioneller Ölzustandssensor für Automobilanwendungen (A Multi-Functional Sensor for Oil Condition Evaluation)