Research On The Piezoelectric Water-jet Propulsion Thruster And Power Supply Design

Now, in the field of micro-thruster in water, the study direction focuses on the general of micro- swimming -robots and micro-pipe robots. And the study on the micro-robots moving in the way of water-jet has just started recently. The water-jet has many typical examples in the biotechnology. The Octopus is called the "water rocket". Using this bionics, the scientists have successfully developed a similar fountain thruster. In general, the water booster pump takes the franc and axial pump as a power plant. But the large bulk limits the miniaturization of underwater craft. If we want to have the bigger breakthrough in size and performances, we must develop a new type of micro-thruster. The basic objective of this paper is to construct a piezoelectric micro water-jet booster using the bionic octopus theory, and study the basic laws and characteristics of the booster to get the optimal performance water-jet robot. In this area, there are many new problems crossed several subjects needed to resolve, a large number of theoretical analysis and experimental research also needed.The full text is divided into seven chapters summarized as the follows. Chapter I. PrefaceIn this chapter, the paper discussed the applications of bionics in micro-robots, leading to the research background of the piezoelectric micro-water-jet propulsion, and explained the importance of water booster by combining the piezoelectric actuator technologies, in particular piezoelectric pump research together. Based on the piezoelectric pump water robot research and analysis, I explained the main contents and elaboration in the end.Chapter II. The basic theory of piezoelectric pumpBased on the reverse piezoelectric effect of the piezoelectric materials, piezo-electric pump is directly or indirectly using the mechanical deformation of the piezoelectric ceramic components to change the pump chamber volume and pressure. Through the one-way valve opened and closed, the piezoelectric pump realizes an orderly one-way flow of fluid. As the basic components, as well as electrical energy conversion components, the performance of piezoelectric ceramic components determines the performance of piezoelectric pump. The basic concept of the piezoelectric effect, the basic physical properties of the piezoelectric material and the important performance parameters, including electrical and mechanical coupling coefficient, piezoelectric constant, constant frequency and mechanical quality factor were studied. The electro-mechanic conversion mechanisms about piezoelectric materials were explained. Four kinds of piezoelectric equations were introduced. The vibration modes, the equivalent circuit resonance characteristics were analyzed. The theory on the basis of piezoelectric actuators was expounded.Chapter III Theoretical analysis and experimental study of the piezoelectric jet-pumpAs the piezoelectric jet-pump plays a main role in pushing the piezoelectric micro-thruster, the performance of piezoelectric pump is extremely important for the thruster. And the preliminary theoretical analysis and experimental research in the piezoelectric pump will be necessary. Although after more than 20 years of development, the piezoelectric pump still does not have a complete design theory system. Sometimes the contradictory conclusion on the same issue of the study shows that some inherent, nature of the phenomenon has not been found or the law or the attention, creating a piezoelectric pump with the vary outputs in the same material and structural properties. And the studies on the piezoelectric water-jet pumps have not been reported by recently. By taking the piezoelectric pump using the composite piezoelectric components as the studied objective, qualitative and quantitative analysis of various elements influences to the export performance of piezoelectric jet-pump provide the theoretical basis for the design and development of high performance jet-pump, in the perspective of system structure.Chapter IV The structure design of the piezoelectric micro water-jet robot and researches in the characteristics.In particular, the design of the piezoelectric pump with high-performance of the flowing output is the key of designing the high-performance piezoelectric thruster. Based on theoretical analysis and experimental research, the output capacity of piezoelectric pump is pushed by the mechanical power and the limits of power and the output volume is relatively low. In order to develop a high-performance water-jet piezoelectric device, a new kind of high-flow output piezoelectric water booster pump needs to design. Because of the coupling of many components such as the valves and fluid movement leading to larger effects on the output piezoelectric pump, the chapter will push for new anti-piezoelectric pump analysis and experimental research.Chapter V Test of the piezoelectric water-jet propulsion thrusterAs a whole, the piezoelectric water-jet propulsion device may be composed of three parts, namely piezoelectric pump,power supply and shell. The water booster pump which is the core of thruster carry out the conversion of electrical energy into mechanical longer hydro power. Road from the outside world into the influent water pumps and high-speed emitted from the nozzle, a piece of thrust to push forward. Prototype piezoelectric pump is pushing anti-parallel piezoelectric oscillator pump mainly on account of the anti-parallel push pump better performance in low-frequency output, which may help to prolong the life of piezoelectric vibrator.Chapter VI Power supply designWithout the corresponding power supply, the piezoelectric water-jet propulsion will not move. Piezoelectric power supply significantly affects the properties of water propulsion. The good power control is the premise for applications of the excellent piezoelectric-driven water-jet propulsion. The purpose of this chapter is designing a practical piezoelectric anti-propeller power for piezoelectric water-jet device to meet the needs for promoting the independence movement. During the design of the power, this paper is mainly responsible for the design of the signal generating circuit. This chapter firstly analysed the actual anti-propeller power, and then discussed the issues on the design of the power supply to pay attention to.Chapter VII SummaryThe main conclusions of the paper, the prospects for piezoelectric water-jet propulsion research, and the direction of future research.