Determination of the ship propulsion power by measuring torsion and angular velocity of the propeller shaft

V diplomski nalogi sem predstavil sistem za merjenje pogonske moči plovil, ki je izveden z meritvijo vzvoja ter vrtljajev gredi. V 1. poglavju sem predstavil ozadje problema ter razloge zakaj je merjenje pogonske moči lahko uporabno. V 2. poglavju sem opisal metode, ki so se zgodovinsko uporabljale za merjenje pogonske moči, najbolj zanimive sodobne metode za merjenje pogonske moči ter zakaj smo se odločili za ta princip merjenja pogonske moči ladij. V začetku 3. poglavja je opisana radijska komunikacija med vezjema in navedene želene specifikacije sistema. Nato pa so opisani posamezni deli, ki sestavljajo sistem na premičnem delu in sistem na nepremičnem delu. Sistem na premičnem delu na gredi sestavljajo wheatstonov mostič z uporovnimi lističi, baterija, ki ga napaja ter vezje na premičnem delu. Opisana je tudi zaščita vezja proti vlagi. Sistem na nepremičnem delu pa sestavljajo Hallovi senzorji z magneti, vezje na nepremičnem delu, LCD prikazovalnik ter vezje za povezavo z računalnikom. Skozi celotno poglavje so opisani načini delovanja celotnega sistema. V 4. poglavju sta opisani obe vezji z blok shemami in opisom posameznih delov, tiskanin in programov na vezjih. Posebno so poudarjeni deli programa, ki skrbijo za nižjo porabo vezja na premičnem delu med delovanjem. Programska oprema za zajem, prikaz podatkov, ki teče na računalniku in njeno delovanje so opisani v 5. poglavju. V 6. poglavju so predstavljeni rezultati meritev, ki so bili izvedeni na pripravi za simulacijo vzvoja gredi z nalepljenimi uporovnimi lističi ter simulirano meritev vrtilne frekvence s signalnimi generatorji. V zaključnem, 7. poglavju, je podana splošna ocena projekta ter možne izboljšave projekta.In this thesis the system for measuring the ship\u27s propulsion power is presented, which is achieved by measuring the torsion and angular velocity of the propeller\u27s shaft. In the 1st chapter the background of the problem and the benefits of measuring the ship\u27s propulsion power are presented. In the 2nd chapter the methods of measuring the propulsion power are described starting from historical to the most interesting modern methods, followed by the reasons for choosing the particular measurement method. In the beginning of the 3rd chapter the radio communication between the two circuits is described and the desired specifications are listed followed by the description of all the parts that form the rotating and the static system. The turning system on the shaft consists from a wheatstone bridge made from strain gauges, the battery and the circuit on the rotating part. A solution in which the circuit is protected against the moisture is also presented. The static system consists of Hall sensors for sensing the rotating magnets, the circuit on the static part, the LCD display and the circuit that is responsible for the communication with the PC. Throughout the whole chapter there are also described the details of operation of the whole system. The 4th chapter is devoted to the description of the circuits by their block diagrams, individual parts and software. Special care is taken when describing the parts of the software that are responsible for the low current consumption of the circuit on the rotating part. The PC software for the acquisition and display of data is described in the 5th chapter. In the 6th chapter results of the measurements, that were taken on a device which simulates the torsion of the shaft where the strain gauges are attached are presented together with a simulation of the measurement of the angular frequency by two signal generators. The final chapter provides a general evaluation and possible improvements of the project