Motion control system is a challenging problem in the area of control systems. It is very useful to demonstrate concepts in linear control such as the stabilization of unstable systems. Motion control system plays important roles in industrial equipment such as machine tools, semiconductor manufacturing systems, and robot systems. One type of motion control system is the point-to-point (FTP) positioning system, which is used to move an object from one point to another point. Linear motion servo system is a machine that moves the cart from one point to another point. This system consists of a cart driven by a DC motor, via a rack and pinion mechanism to ensure consistent and continuous traction. Till date, many types of controllers have been proposed and evaluated for positioning systems. Two types of controllers discussed in this thesis are Proportional-Velocity (PV) and Nominal Characteristic Trajectory Following (NCTF). The experimental results showed that the PV was successfully implemented which controlled the settling time, rise time, and steady-state error of the desired position. However, the overshoot performances show its disadvantages. Additionally, the PV controller design is a time-consuming process, since model and parameters of the linear motion servo system are needed. Therefore, the needs for higher performance controller become important for the simplicity of the controller design. Hence, the investigation proceeds with the non-model-based NCTF controller to control the cart position of the linear motion servo system. The NCTF controller consists of a Nominal Characteristic Trajectory (NCT) and PI compensator. The NCTF controller was designed based on a simple open-loop experiment of the object. The experimental results showed that the NCTF controller is more effective for controlling the position of linear motion servo system than the PV controller.

关键词：标称特性轨迹跟踪；性能比较；运动控制系统

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This project centered on a close interaction between the TCON Division of Fire line, Inc. and various individuals affiliated with the College of Science, Technology, Engineering, and Mathematics (STEM) at Youngstown State University (YSU). Fireline, a local company within 10 minutes walking distance from the YSU campus core, has developed a unique process that utilizes displacement reactions to transform ceramic preforms into ceramic-metallic co-continuous interpenetrating phase composites with enhanced properties while retaining the original shape and dimensions of the preform. Through initial development efforts, it was discovered that TCON(TradeName) composite materials have extraordinary macro-, micro-, and nanoscale features that lead to their exceptional properties ideal for applications that require cost effective, lightweight materials. The unique properties of TCON composites in general are derived from the fine interlocking of ceramic and metallic phases throughout the composite microstructure. The ceramic phase provides high stiffness, low density and high strength to the composite, while the continuous network of reinforced metal gives high thermal & electrical conductivity, and high fracture toughness to the material. Such properties make these materials excellent candidates for replacing traditional materials in a number of applications, such as high wear/corrosion resistant refractory shapes for molten metal transport and/or containment in industrial processes (the major area in which Fireline currently commercializes some of its TCON products), or for new applications, including light weight, high strength components for vehicle braking systems.

关键词：二氧化碳；催化剂；中心的运输与材料工程

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Many engineering systems can be characterized as complex since they have a nonlinear behaviour incorporating a stochastic uncertainty. It has been shown that one of the most appropriate methods for modelling of such systems is based on the application of Gaussian processes (GPs). The GP models provide a probabilistic non-parametric modelling approach for black-box identification of nonlinear stochastic systems. This chapter reviews the methods for modelling and control of complex stochastic systems based on GP models. The GP-based modelling method is applied in a process engineering case study, which represents the dynamic modelling and control of a laboratory gas-liquid separator. The variables to be controlled are the pressure and the liquid level in the separator and the manipulated variables are the apertures of the valves for the gas flow and the liquid flow. GP models with different regressors and different covariance functions are obtained and evaluated. A selected GP model of the gas-liquid separator is further used to design an explicit stochastic model predictive controller to ensure the optimal control of the separator.

关键词：非线性行为；高斯工程；控制器

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The purpose of this project is to is to investigate the possibility of exploiting the flexibility inherent to micro air vehicle structures to create small-amplitude oscillations that delay stall and increase lift. Initially two-dimensional rigid airfoils undergoing small amplitude plunging oscillations are considered, this is then expanded to finite wings and finally flexible wings. For the 2D airfoil case two mechanisms of lift generation are identified: deflected jets for pre-stall angles of attack and convected leading- edge vortices for post-stall angles of attack. For rigid airfoils plunging with small-amplitude, two mechanisms of lift enhancement have been identified: deflected jets and convected LEVs. For finite wings oscillating at post-stall incidence, similar lift-enhancing convected LEVs are observed, however the flow field is more complicated. For oscillating flexible wings appropriate spanwise flexibility can significantly enhance lift performance. In terms of the flow field, the rigid wing exhibits weak vortical structures near the leading-edge, which are essentially the three-dimensional version of the LEV dipole observed for flat plate airfoils. Conversely the flexible wing exhibits a strong convected LEV, strong tip vortex and thus high lift.

关键词：翼型；攻角；长宽比；非对称流动；岔流

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Mechanical systems with synchronization functionality have been used for many complex production tasks that cannot be carried out by a single machine and/or individual mechanism. Synchronized control approach is one of the key issues to achieve the synchronized motion of mechanical systems, which attracts more and more attention from academic research to applications. There are many types of mechanical systems that require synchronized control, which have different kinematics and dynamics. It is not an easy job to use a unified synchronized control algorithm for all mechanical systems. This chapter summarizes the work on synchronized control mainly developed by the authors and their colleagues. In the presentation it tries to use several classical mechanical systems to show the design philosophy of the synchronized control systems, and consequently establishes a reader/user-friendly framework with tutorial, survey, applications, and potential research expansion.

关键词：机械系统；同步控制；交叉耦合的错误

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Catalytic converters (CATCONs) are required by Federal law to be installed in nearly all gasoline- and diesel-fueled onroad vehicles used in the United States. About 85 percent of the light-duty vehicles and trucks manufactured worldwide are equipped with CATCONs (Ashok Kumar, Director, A1 Specialized Services & Supplies, Inc., written commun. July 10, 2012). These vehicles include buses, cars, light- and heavy-duty trucks, and motorcycles. Many offroad vehicles, such as trail bikes and all-terrain recreational vehicles, are also equipped with CATCONs, but offroad vehicles are not addressed in this paper (Manufacturers of Emission Controls Association, 2008). Portions of the CATCONs (called monoliths) are recycled for their platinum-group metal (PGM) content and for the value of the stainless steel they contain. The cerium contained in the monoliths, however, is disposed of along with the slag produced from the recycling process. Although there is some smelter capacity in the United States to treat the monoliths in order to recover the PGMs, a great percentage of monoliths is exported to Europe and South Africa for recycling, and a lesser amount is exported to Japan. There is presently no commercial-scale capacity in place domestically to recover cerium from the monoliths. Recycling of cerium or cerium compounds from the monoliths could help ensure against possible global supply shortages by increasing the amount that is available in the supply chain as well as the number and geographic distribution of the suppliers. It could also reduce the amount of material that goes into landfills.

关键词：大气；稀有气体；空气污染

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转弯制动性能对半挂汽车列车的制动安全有重大影响,针对我国目前半挂汽车列车转弯制动试验标准缺失,传统的单车试验设备不适用于半挂汽车列车等问题,本文中从试验系统搭建、系统安装方式和试验方法与评价等方面对半挂汽车列车转弯制动试验进行了探索性研究。结果表明:半挂汽车列车转弯制动过程中侧向加速度、制动减速度、横摆角速度和牵引车的俯仰角随车速的升高而增加。建议半挂汽车列车转弯制动试验中车速不超过30km/h,转弯半径不小于25m。

关键词：半挂汽车列车；转弯制动；试验系统；试验方法

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基于1台高压共轨涡轮增压柴油机,采用不同的预喷正时、预喷油量与后喷正时等,研究了多次喷射对燃烧放热、排放生成与燃油经济性的影响,以实现均质压燃和低温燃烧过程。研究结果表明:随预喷正时提前,缸内峰值压力降低,主燃阶段的滞燃期缩短,NOx和炭烟排放均降低;随预喷油量增加,预喷阶段燃烧的放热率和最大压力升高率增大,NOx和HC排放增大,而PM和CO排放降低;随后喷始点推迟,缸内压力与主放热率峰值差异变小,NOx排放降低,但炭烟排放先增大后逐渐降低。

关键词：直喷式柴油机；多次喷射；预喷正时；放热率；排放

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在高压共轨燃油喷雾试验台上对正丁醇体积掺混比分别为0%,5%,10%和20%的柴油-正丁醇混合燃料的宏观喷雾特性进行了研究。结果表明:在相同共轨压力下,随着背压的增加,喷雾锥角增大,喷雾贯穿距减小;在相同背压下,随着共轨压力的增加,喷雾贯穿距和喷雾锥角均逐渐增大,但当共轨压力增大到110 MPa时,二者不再增大;在相同背压和相同共轨压力下,喷雾贯穿距和喷雾锥角随着正丁醇比例的增加逐渐增大,说明在柴油中混合一定比例的正丁醇可以提高燃料的雾化质量。

关键词：柴油；正丁醇；混合燃料；背压；共轨压力；喷雾贯穿距；喷雾锥角

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The paper proposes a method to reduce operational force in a bilateral teleoperation system that realizes simultaneity property under communication delay. A bilateral control that realizes simultaneity property is previously proposed, which is achieved by buffering the force information. It focused on the fact that force information from the master motor is the pure information that actuates the motor, therefore, timing of the force information input is corrected. However, the control system requires large force when operator tries to operate the system. The paper clears the reason and the problem is solved by utilizing the delayed position information of the own system. The proposed control system is designed to mix present and buffered position information to reduce the operational force. The delayed information can easily affect the stability problem, therefore, phase compensator is used. The validity of the proposed method is confirmed by experiments.

关键词：加速度控制；双向控制系统；通信延迟

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