Position and speed control of the torpedo present a real problem for the actuators because of the high level of system nonlinearity and because of the external disturbances. The nonlinear systems control is based on several different approaches, which include the sliding mode control. This chapter deals with the basic concepts, mathematics, and design aspects of a control for nonlinear systems that make the chattering effect lower. As solution to this problem we will adopt as a starting point the high order sliding mode approaches and then the PID-sliding surface. Simulation results show that this control strategy can attain excellent control performance with no chattering problem.

关键词：滑模控制；PID控制器；抖振现象；非线性系统

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In this chapter we describe an iterative two-layer hierarchical approach to MPC of large-scale linear systems subject to coupled linear constraints. The algorithm uses constraint tightening and applies a primal-dual iterative averaging procedure to provide feasible solutions in every sampling step. This helps overcome typical practical issues related to the asymptotic convergence of dual decomposition based distributed MPC approaches. Bounds on constraint violation and level of sub-optimality are provided. The method can be applied to large-scale MPC problems that are feasible in the first sampling step and for which the Slater condition holds (i.e., there exists a solution that strictly satisfies the inequality constraints). Using this method, the controller can generate feasible solutions of the MPC problem even when the dual solution does not reach optimality, and closed-loop stability is also ensured using bounded suboptimality.

关键词：迭代两层；大型线性系统耦合；MPC

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针对某柴油机连杆小头衬套松脱问题,提出2种连杆小头结构改进方案,分别从安装状态的衬套背压、工作状态的衬套滑移以及小头内孔变形三方面研究关键参数及敏感区域对结构刚度的影响。结果表明:增加衬套壁厚、增大连杆小头支撑刚度可有效增大衬套背压,减小内孔变形,降低衬套由切向力所导致的滑动风险。

关键词：连杆小头；结构设计；背压；滑移

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In this paper the main idea is to control the flight of an F-16 airplane using fuzzy system and PID controller to achieve the control. In general, to control the total flight is necessary to control the angle of the elevator, angle of the aileron and the angle of the rudder. For this reason, 3 fuzzy systems are used to control the respective angles. In this paper the fuzzy systems are presented with results using the simulation plant of the airplane.

关键词：F-16飞机；电梯；控制器

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A high-load endurance test was performed on the tail drivetrain of an H-60 Blackhawk helicopter to determine the resistance to gear tooth fracture under power levels exceeding the maximum continuous rating. During posttest inspection, it was found that a tooth had broken off of the tail takeoff spiral bevel gear. In addition, a moderate spall was found on the outer race of the intermediate gearbox input gear shaft support bearing. There were no obvious indications of the gear tooth failure during the duration of the test, making the determination of the time of tooth fracture critical to understanding the resistance of the H-60 tail drivetrain to overloads. This report analyzes vibration data sampled periodically throughout the test to determine the initiation time of these two specific mechanical failures. Both faults occurred naturally in a system environment, making the dataset of particular interest. Several existing gear and bearing vibration analysis techniques were utilized. These methods clearly identified the time of initiation of both the spiral bevel gear tooth fracture and the bearing spall. The capability of the different analysis methods relative to predicting gear tooth crack and bearing spall initiation are compared.

关键词：轴承；诊断设备；故障（力学）；故障诊断

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针对车辆上同时应用排气制动与涡轮增压的情况,研究了排气制动对增压器轴向载荷的影响。通过排气制动与增压器联动试验测量了增压器在各个工况下的轴向载荷,从而确定了数值计算所需的边界条件,并通过数值计算获取了增压器在各个工况的轴向载荷的分布情况。结果表明,与正常工况相比,增压器在排气制动工况下其轴向载荷显著增大,且排气背压越高,增压器轴向载荷越大;涡轮级轴向载荷反向且增大;压气机级轴向载荷显著下降,但方向不变。

关键词：增压器；排气制动；轴向载荷；联动试验

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A study of the behavior and evaluation of the Ant Colony Optimization algorithm (ACO) in Type-1 and Type-2 Fuzzy Controller design is presented in this chapter. The main objective of the work is based on the main reasons in tuning membership functions for the optimization Fuzzy Controllers of the benchmark problem known as the Water Tank with the algorithm of Ant Colony Optimization. For the design of Type-1 and Type-2 Fuzzy Controllers for particular applications, the use of bio-inspired optimization methods have helped in the complex task of finding the appropriate values of the parameters and the structure of fuzzy systems. In this research we consider the application of ACO as the paradigm that aids in the optimal design of Type-1 and Type-2 Fuzzy Controllers. We also analyzed that in evaluating the uncertainty, the results in the simulation are better with Type-2 Fuzzy Controllers. Finally, provide a comparison of the different methods for the case of designing Type-1 and Type-2 Fuzzy Controllers with Ant Colony Optimization.

关键词：蚁群优化算法；模糊控制器；仿真

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采用理论计算、数值仿真和实验相结合的方法探讨了材料、有无芯轴、芯头个数和芯棒伸出量对汽车防护杠用不锈钢管绕弯成形质量的影响。结果表明:相同工艺条件下,不锈钢SUS304管材比碳素钢Q235A更易产生截面畸变,但外侧壁厚减薄率较小;材料相同时,有芯轴支撑管材切向压应力和拉应力最大值的差值较小,材料流动更加均匀,能很好地抑制管材的截面畸变和失稳起皱;芯头个数是影响截面变形的最重要因素,芯头个数为3时,截面畸变率最小,其最大值仅为4.2%;芯棒伸出量过小,管材内侧容易起皱,截面畸变率较大;而伸出量过大时,管材外侧壁厚减薄严重,甚至导致拉裂;芯棒伸出量为9mm时,管材的弯曲成形质量最好。仿真结果与理论解析解和实测值吻合较好。

关键词：汽车防护杠；大口径薄壁管；绕弯成形；工艺参数；数值仿真

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基于Atkinson理论循环建立混合动力汽油机的性能仿真模型,确定出合适的压缩比与配气正时。分别采用增加活塞顶面凸起高度(上凸型燃烧室)和减小缸盖上燃烧室高度的方式来满足Atkinson循环汽油机对压缩比的要求。同时为适应紧凑结构减小气门升程、直径(紧凑型燃烧室)。通过三维CFD计算分析,比较了两种燃烧室缸内燃烧及流动特性,发现紧凑型燃烧室能够在火核形成及扩散时期在缸内产生更高的湍动能,有利于加快火焰传播,使燃烧持续期缩短9.8%~24.4%,可显著提高燃油经济性。在混合动力用Atkinson循环发动机开发中使用紧凑型燃烧室,具有重要的应用价值。

关键词：混合动力；Atkinson循环发动机；燃烧室；湍动能

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One-dimensional transient heat transfer analysis is frequently used to provide quick estimates of the performance of thermal protection system concepts for reentry systems. While finite difference techniques are commonly employed when solving simple single-material thermal problems, more complex cases with multiple layers can complicate the numerical implementation. A control volume analysis is used in the present work to derive a finite volume approach to the 1-D thermal analysis problem using generalized coordinates. Details of the numerical implementation are also discussed to highlight how this technique can simplify the overall solution process. Finally, two example problems are used to validate the accuracy of the approach, one of which involves analysis of a multilayer TPS problem with non-uniform grid spacing.

关键词：传热；热分析；复合材料；有限元法

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