Research On Longitudinal Control Of Underwater High Speed Vehicle

High-speed performance of underwater weapon has always been a urgent pursuit.However, the speed of conventional underwater weapon is difficult to break through thelimitation of40m/s under the action of the fluid resistance. Supercavitation drag reductiontechnique appears to bring the restrictions a revolutionary breakthrough. It can make theunderwater vehicle’s resistance decrease about90%, to realize the "flying" speed of more than100m/s. The high speed development of underwater vehicle has a great influence. Oncebreaching the key technology, it will completely change the future battle mode. At present,naval powers all over the world have invested heavily in the research and development ofsupercavitation weapons. This paper will detailed analyze the longitudinal motioncharacteristics of high-speed underwater navigation vehicle. Based on establishing itsmathematical model, this paper will deeply study the longitudinal motion control in slidingmode control algorithm. This paper’s main contents are as follows:First of all, introduce the research background, purpose and significance, research trendand related products at home and abroad. Analyze some countries worldwide supercavitationtechnology research progress and achievement. Analyze the dynamic control strategy researchon high-speed underwater navigation vehicle. the basic theory of supercavitation is introducedin detail according to the relevant literature, analyzing the formation process and producingcondition of supercavitation, studies the two widely used model of the cavitation. On the basisof the analysis of the high-speed underwater navigation vehicle’s structure characteristics andthe actuator design, study a stern rudder configuration schemes of the navigation vehiclemotor strategy.Secondly, study on the dynamic characteristics of the high-speed underwater navigationvehicle, analysis of supercavitation state bodies, by the force in the water. These forcesinclude lift and drag of cavitation device, friction sliding force and sliding area navigationbody tail, lift and drag fins, propulsion system to generate thrust. establish a proper high-speed underwater navigation vehicle coordinate system, and analyze navigation vehicledynamic characteristics through the appropriate coordinate system transformation. Using therigid body’s dynamics theory and potential flow related theory, establish a mathematicalmodel of high-speed underwater navigation vehicle with the configuration of single freedomdegree cavitation device. Once again, in view of the high-speed underwater navigation vehicle model exist systemvariable parameter, bounded uncertain disturbance and model uncertainty, according to thesliding mode control invariance, design high-speed underwater navigation vehiclelongitudinal motion controller with the application of sliding mode variable structure controlalgorithm. In addition, according to the navigation vehicle mathematical model withparameter perturbation and external disturbance, establishing a sliding mode controller usingthe mean of reaching law. And the simulation shows that this controller is validity to controlthe system uncertainties, shows that the control algorithm is very robust.Finally, to solve the problem that the uncertainty disturbance upper bound of real systemis not easy to get, quotes adaptive controlling ideas to design sliding mode controller.Establish longitudinal motion model of high-speed underwater navigation vehicle, and designthe adaptive integral sliding mode controller to realize the longitudinal motion control ofhigh-speed underwater navigation vehicle. In maintain a strong robustness, the system canautomatically adapt to the uncertain factors. Finally, the simulation result proves theeffectiveness of the control algorithm.