First experimental tests on the prototype of a capacitive oil level sensor for aeronautical applications

In this paper, the design, the prototyping, and the first experimental tests of a Capacitive Oil Level Sensor (CLS) intended for aeronautical applications are described. Due to potentially high vibrational stresses and the presence of high electromagnetic interferences (EMI), the working conditions on aircraft can be considered quite harsh. Hence, both the sensing part and the conditioning circuit should meet strict constraints. For this reason, in the design phase, great attention has been paid also to the mechanical characteristics of the probes. All the design aspects are exposed and the main advantages concerning alternative level sensing techniques are discussed and the preliminary experimental results of sensitivity, linearity, hysteresis, and settling time tests are presented and commented.