In those reflective configurations, multipoint measurements are based on using a new single receiving fiber for each measuring point, meaning a complex reception unit with wider area and weight [10]. Using these multiple receiving fibers, the multipoint approach is also used in some U bend configurations [6] or coupler configurations [11]. Other level sensors are based on serial U bend configurations selleckchem but using cladding removed and core-polished bends, but these are more fragile configurations in the long term [12]. Some configurations are based on rod-type or U bend sections all along the same fiber, but with the jacket completely removed from the fiber [13], being less robust to undesirable wetting of liquids with high surface tension.
Other sensors use fibers with clad and unclad zones [14] related to a specific code that are not easily automated for manufacture and they also need complex reception schemes, e.g., an optical decoding system, being difficult to develop portable devices in that case [15]. Intrusive schemes based on Fiber Bragg Grating (FBG) and Long Period Fiber Grating (LPG) sensors with mm resolution have also been reported [16], but they are fragile and non cost-effective technologies. On the other hand, optical solutions for liquid-level detection allowing continuous measurements have also been reported [17,18]. Nevertheless, in the solution proposed in [18] objective lenses need to be used as the light launched inside the tank tends to scatter and spread.
In this paper a U shaped bend configuration with only the jacket removed at discrete measuring points and flexibility to be placed on those non-symmetric points where the users need to know the liquid level will be proposed. A single fiber will be used to address and collect information for all sensing points [19].Paramotoring and powered paragliding are very recent sports which are Batimastat seeing a growing demand for users’ entertainment. Some pictures of the real application scenario are shown in Figure 1. A possible classification depending on basic features is given in Table 1. At the same time both sports are continuously increasing the demand of new and more sophisticated flight instrumental, but usually lack of real fuel level measurement, and estimations of the latter have to http://www.selleckchem.com/products/z-vad-fmk.html be done by relating the tank volume and the fuel consumption by mental arithmetic. Some exceptions can be found [20,21], but fuel probes work on the principle of changing capacitance and with specific housing to reach intrinsically safe sensors. Taking advantage of the aforementioned polymer optical fiber properties, in this work a compact POF intensity-based sensor for fuel level monitoring is developed thus providing a more significant safe flying scenario.