This thesis presents controllers that use relative range and bearing measurements to steer unmanned aerial vehicles (UAVs) to circular trajectories around stationary, constantly moving and constantly accelerating targets. The range and bearing to the target, along with their derivaties are estimated. These, along with the estimated local heading of the UAVs, are used in the control law, and to estimate the velocity of the target. In this work, six controllers are presented. The controller for a stationary target is derived using Lyapunov's direct method, and feedback linearization is used for the constant velocity and accelerating targets. A new controller is proposed to control the direction of encirclement for moving targets, using Lyapunov's direct method. Additional terms are introduced to maintain a temporally equi-spaced formation around the targets. Theoretical proofs are provided for all controllers using Lyapunov theory. Numerical simulations show vehicles converging to circular formations around both stationary and moving targets. Results are shown using MATLAB simulations with Gaussian noise added to the measurements. Further, a technique is proposed for information exchange between UAVs, with bounds provided for the time taken to dissipate information throughout the system in a scenario with multiple groups of UAVs tracking multiple targets.

蔣中正和毛澤東，同為二十世紀中國的重要領導人物，其影響不僅是在政治上，更在軍事上。兩人都是偉大的戰略指導者和軍事理論家，或者至少他們的追隨者如此宣稱。在超越領袖崇拜的今天，這個形容仍是事實嗎？ 蔣、毛第一次在軍事上對決是在江西第三次圍剿。毛澤東已取得前兩次反圍剿的勝利，他發展出一個理論應付國軍的圍剿：集中兵力各個擊破國軍分散的各路。加上共產黨的動員力量，國軍的圍剿相當困難。蔣中正有鑑於此，做出了戰略上的轉向，新的戰略結合碉堡戰術、封鎖、「三分軍事七分政治」等方針。最終對贏得了第五次圍剿。毛澤東在長征中重新取回領導權，他馬上面對的是國軍在貴州的新一波圍剿。由於遠離蘇區戰鬥，因此只有很少的補給和援助。會戰展開也不順利，土城、魯班場之戰戰敗，而僅以慘勝贏得遵義之戰。但毛終究設法逃出蔣的包圍圈，並離開貴州與紅四方面軍會師。由於毛澤東和張國燾的戰略歧見，毛澤東獨自帶領紅軍北上抵達陝北與當地紅軍會合。紅軍東征入晉，宣稱要到華北抗日。但為蔣增援山西的中央軍所擊退。在紅四方面軍北上之後，為了在甘肅、寧夏打通蘇聯援助路線，紅軍渡過黃河。但為蔣中正命令下的國軍所切斷，這個行動最終導致了西路軍的潰滅。 在剿共戰爭當中，蔣中正和毛澤東各自研發出他們的理論與對中國戰爭的認知。他們的共識是中國的戰爭是不同於外國的戰爭的。此階段可以視為他們的軍事思想奠基時期。毛澤東所寫的「中國革命戰爭的戰略問題」成為以後他的軍事著作的先聲。另一方面，蔣中正對此的經驗則比較是方法上的，以軍官訓練團訓練軍官及幹部、親自編撰各式「手本」等戰術教材，這些方法的延續持續到抗戰之後，甚至到臺灣時期。 / Chiang Kai-Shek and Mao Ze-Dong, two great leader of 20th century China, not only politically but also militarily. Both man are, or so claim separately by their followers, are great stretegist and military theorist. Beyond the worship of both man, is that true? Chiang and Mao’s first military encounter was the third encirclement campaign of Jiang-Xi. Mao already won the first two, he develop a theory to counter Nationalists’ encirclement by concentrating strength and attack the enemy detachment separately. Along with the mobilizational power of Communists, Nationalists’ encirclement campaign turns out very difficult. Chiang realize that, and making a dramatic turn of strategy, combine with bunker tactics, blockade, and political mobilization of people. Chiang eventually won the fifth encirclement campaign over the Mao-absence Communists. Mao took back his command during the Long March. He soon faces the Nationalists’ encirclement again in Guizhou. This time he is not fighting on a soviet area, therefore gain little support and reinforcement. The battles are not quite well either, Lost two of them and won one costly. But he still manage to escape from Chiang’s encirclement, and leave Guizhou to rendezvous with other Red Army. Because of strategy difference between Mao and another Communist leader Zhang Guotao, Mao leads his troop go north to Shaanxi, rendezvous with local Red Army. Mao attacks Shanxi by claiming they want to fight Japanese evasion at North, driven back by Chiang’s reinforcement to local warlord Yan Xishan. To fulfill the strategy goal of reaching USSR to get supplies, Communists launch another campaign in Ningxia and Gansu and crossed Yellow River. But the Red Army been cut off by Chiang’s nationalist army, this later leads to the elimination of the west side detached Red Army. During the war, Chiang and Mao both develop their own theory and knowledge of War in China, which they both believe in common is different from foreign wars. The period of first Chinese civil war, can be seen as their military thought’s foundation. Mao wrote “Problems of Strategy in China's Revolutionary War” to conclude this war, became the pioneer of his military works later on. Chiang, on other hand, took the experience most in method way: retrain officers in special facility, write tactic handbooks.These methods cotinuely used by Chiang on later wars against Japan, even in Taiwan in his late years.