在所建整车七自由度模型的基础上,深入分析了电子稳定程序(ESP)对电动助力转向系统(EPS)工作模式的影响,设计了非线性滑模控制器,并计算出整车横摆运动所需的稳定控制力参考值,运用功能分配的方法对稳定控制力进行合力动态分配,同时考虑在低附着系数路面汽车车轮自回正力矩的严重缺失,从而提出基于ESP作用的回正力矩补偿控制策略,对EPS的工作模式进行修正。硬件在环仿真和软件仿真的结果表明,提出的控制策略不仅改善了转向系统的回正性能,而且能够使车辆快速、准确地恢复到稳定行驶的状态,提高了其操纵稳定性。

关键词：电动助力转向；电子稳定程序；功能分配；回正力矩；硬件在环仿真

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H_2 and H_∞ optimal control are two important breakthroughs in modern robust control. In recent years, the H_2 and H_∞ controller design techniques have gained a lot of research attention. Both have strong theoretical basis and are efficient algorithms for synthesizing optimal controllers. The performance of H_2 robust controller is useful to handle stochastic aspects such as measurement noise and capture the control cost. In the robust H_2 approach, the controller is designed to minimize an upper bound on the worst case H_2 norm for a range of admissible plant perturbations. When a model under analysis is applied with H_2 robust controller, the closed loop system will have a good dynamic system performance, but it has poor robustness for the external disturbances of the uncertain system model. The performance of H_∞ is convenient to enforce robustness to model uncertainty, but it is based on compromising system performance. Their combination, the mixed H_2/H_∞ allows intuitive quadratic performance specifications of the H_2 synthesis with robust stability requirements specifications expressed by the H_∞ synthesis. In time domain aspects, satisfactory time response and closed loop damping can often be achieved by enforcing the closed loop poles into a predetermined region of the left half plane. Combining these requirements to form so-called mixed H_2/H_∞ design with regional pole placement constraints allows for more flexible and accurate specification of closed-loop behavior. This chapter introduces the work of design of improved LMI-based robust output feedback controller and related simulations.

关键词：线性矩阵不等式（LMI）；电力系统稳定器（PSS）；鲁棒控制

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Force estimation is one of the most important techniques in the robot control application. In this research, acceleration sensor based load-side disturbance observer (ALDOB) is proposed and developed by integrating an acceleration sensor on the load side and the optical encoder on the motor side in order to estimate external force. The enhancement of the force estimation was found to increase. Good estimation of force and robust force control could be obtained using ALDOB observer. The simulation results are provided to illustrate the performance of the proposed algorithms. A flexible robot model was established to simulate the robot dynamic in force control, and the results agree with the analysis.

关键词：力控制；扰动观测；加速度传感器

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This measure guideline offers additional recommendations to heating, ventilation, and air conditioning (HVAC) system designers for optimizing flexible duct, constant-volume HVAC systems using junction boxes within Air Conditioning Contractors of America (ACCA) Manual D guidance (Rutkowski, H. Manual D -- Residential Duct Systems, 3rd edition, Version 1.00. Arlington, VA: Air Conditioning Contractors of America, 2009.). IBACOS used computational fluid dynamics software to explore and develop guidance to better control the airflow effects of factors that may impact pressure losses within junction boxes among various design configurations (Beach, R., Prahl, D., and Lange, R. CFD Analysis of Flexible Duct Junction Box Design. Golden, CO: National Renewable Energy Laboratory, submitted for publication 2013). These recommendations can help to ensure that a system aligns more closely with the design and the occupants' comfort expectations. Specifically, the recommendations described herein show how to configure a rectangular box with four outlets, a triangular box with three outlets, metal wyes with two outlets, and multiple configurations for more than four outlets. Designers of HVAC systems, contractors who are fabricating junction boxes on site, and anyone using the ACCA Manual D process for sizing duct runs will find this measure guideline invaluable for more accurately minimizing pressure losses when using junction boxes with flexible ducts.

关键词：空气流量；计算流体动力学；配置

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研究通过试验辨识获得最优预瞄加速度驾驶员模型物理参数的方法。采用时域辨识方法确定模型传递函数,采用非线性最小二乘法确定传递函数中所包含的物理参数,利用已知目标函数优化预瞄时间和反应时间,针对仿真数据进行了辨识分析。结果表明,该方法对驾驶员模型物理参数的辨识具有良好的效果。

关键词：驾驶员模型；最优预瞄加速度；参数辨识

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The synthesis and physical properties of new silicon-containing polyfunctional cyanate ester monomers tris(4-cyanatophenyl)methylsilane and tetrakis(4-cyanatophenyl)silane, as well as polycyanurate networks formed from these monomers are reported. The higher cross-linking functionality compared to di(cyanate ester) monomers enables much higher ultimate glass transition temperatures to be obtained as a result of thermal cyclotrimerization. The ability to reach complete conversion is greatly enhanced by cocure of the new monomers with di(cyanate ester) monomers such as 1,1-bis(4-cyanatophenyl)ethane (LECy). The presence of silicon in these polycyanurate networks imparts improved thermochemical stability in air compared to carbon-containing analogs in cases where the thermochemical performance in air is significantly worse than under nitrogen. The water uptake in the silicon-containing networks examined is 4 - 6 wt% after 96 hours of immersion at 85 degrees C, considerably higher than both carbon-containing and/or di(cyanate ester) analogs.

关键词：固化动力学；固化；氰酸酯；氰酸酯

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Weapons release at supersonic speeds from an internal weapons bay is a highly desirable capability. To ensure a successful release at multiple Mach numbers, the aerodynamic environment must be well-understood and repeatable, with a robust system for safe testing of store separation. For this reason, experimental methods were used to investigate the characteristics of a scaled WICS bay with a length-to-depth ratio of 4.5 at multiple Mach numbers and stagnation pressures. Three new nozzles were designed, manufactured, and characterized for the AFIT small supersonic tunnel, yielding freestream Mach numbers of 2.22, 1.84, and 1.43. In addition, a control valve was recon gured to achieve stagnation pressures as low as 1.0 psia. These nozzles were then used in conjunction with piezosresistive pressure transducers and high-speed Schlieren photography to capture the time-varying pressure signal and spectra of the cavity. Resonant frequencies from these tests matched very well with analytically predicted results for the Mach 2.3 and Mach 1.9 nozzles. The Mach 1.5 nozzle posed some di culties for the con guration tested due to shocks re ecting into the cavity. The Mach 2.3 nozzle was utilized in freedrop testing of a 1:20 scaled sphere and compared to computational simulations. The computational solution was obtained using the OVERFLOW solver with incorporated 6DOF motion and the DDES/SST hybrid turbulence model. Analysis of the Schlieren video generated by the experimental tests allowed direct comparison of computational and experimental trajectories. Measured trajectories compared closely to computational trajectories, especially for the lowest stagnation pressure settings, where heavy Mach scaling yielded operationally relevant results, despite the small scale of the tests.

关键词：压力传感器；谐振频率；罗斯特模式

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在柴油机润滑油中分别加入不同比例的硬脂酸甲酯、油酸甲酯和亚油酸甲酯,通过高温氧化试验对柴油机润滑油的氧化过程进行了模拟。采用旋转氧弹法和傅里叶红外光谱对柴油机润滑油的氧化诱导期和氧化衰变产物结构组成进行了试验分析。结果表明,不饱和脂肪酸甲酯的存在加速了柴油机润滑油的氧化,且不同质量等级的脂肪酸甲酯对柴油机润滑油氧化速率影响程度不同,其由大到小顺序依次为CD 15W/40+亚油酸甲酯,CD 15W/40+油酸甲酯,CD 15W/40+硬脂酸甲酯,CD 15W/40。

关键词：不饱和脂肪酸甲酯；柴油机油；氧化衰变；模拟试验

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本文提出一种基于多目标优化的纯电动车动力系统的参数匹配方法。该方法以最高车速、加速时间和100km电耗等多个整车性能指标作为优化目标,以传动比为优化变量建立参数匹配优化模型;再以该车型的最基本性能指标作为约束条件得到传动比的可行域,在可行域中采用多目标遗传算法对优化问题进行求解;求出固定传动比变速器和两挡变速器两种情况下的Pareto最优解集,作为备选方案集;综合对比不同电机的备选方案集,确定最终的参数匹配方案,并进行样车的开发。转鼓试验结果表明,所开发车辆达到设计的性能指标,验证了所提出的参数匹配方法的有效性。

关键词：纯电动车；Pareto最优解集；参数匹配；多目标优化；遗传算法

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本文中提出一种变逻辑门限值的车辆稳定性控制策略,并重点对动态逻辑门限值的确定方法进行了深入的研究,以改善不同工况下车辆的稳定性。由于逻辑门限值受到行驶环境和运动状态的影响,因此利用模糊推理的方法分别确定横摆角速度偏差和质心侧偏角变化率的门限值;然后利用逻辑门限PI控制方法计算出附加横摆力矩;最后在电控液压制动(EHB)系统中实现了附加横摆力矩。仿真结果表明,当车辆失稳时,所提出的控制策略能及时对车辆进行稳定校正控制,提高了车辆行驶的安全性。

关键词：车辆稳定性；动态逻辑门限值；模糊控制器；电控液压制动系统

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