数学与系统科学研究院学术报告
报告题目：A Singular Perturbation Approach for Time-Domain Assessment of Phase Margin
报 告 人：Jianchao Zhu
时间地点：7月27日上午10:30 - 11:30, 晨兴510室
摘要：This talk discusses the problem of time-domain assessment of the Phase Margin (PM) of a Single Input Single Output (SISO) Linear Time-Invariant (LTI) system using a singular perturbation approach, where a SISO LTI fast loop system, whose phase lag increases monotonically with frequency, is introduced into the feedback loop of a nominal system as a singular perturbation with a singular perturbation (time-scale separation) parameter ε. First, a bijective relationship between the Singular Perturbation Margin (SPM) εmax and the PM of the nominal (slow) system is established with an approximation error on the order of ε2. In proving this result, relationships between the singular perturbation parameter ε, PM of the perturbed system, PM and SPM of the nominal system, and the (monotonically increasing) phase of the fast system are also revealed. These results make it possible to assess the PM of the nominal system in the time-domain for SISO LTI systems using the SPM with a standardized testing system called ”PM-gauge,” as demonstrated by examples. PM is a widely used stability margin for LTI control system design and certification. Unfortunately, it is not applicable to Linear Time-Varying (LTV) and Nonlinear Time-Varying (NLTV) systems. The approach developed here can be used to establish a theoretical as well as practical metric of stability margin for LTV and NLTV systems using a standardized SPM that is backward compatible with PM. A road map for future work on extension of the proposed SPM as a stability margin for LTV and NLTV will be discussed.
报告人简介：
Biographical Sketch for Dr. Jianchao (Jim) Zhu
February 27, 2011
Dr. J. Jim Zhu received his Master of Science in Electrical Engineering, Master of Art in Mathematics, and Doctor of Philosophy in Electrical Engineering majoring in control engineering in 1984, 1986 and 1989, respectively, from the University of Alabama in Huntsville (UAH). After serving one year post-doctoral Research Associate at UAH, he joined the faculty of the Department of Electrical and Computer Engineering of the LouisianaStateUniversity in 1990 as Assistant Professor and subsequently became Associate Professor. Since 2000 when Dr. Zhu joined the faculty of the School of Electrical Engineering and Computer Science of the Ohio University (OHIO), he has been holding a tenured position of Professor. Dr. Zhu's main research area and contribution is in time-varying linear and nonlinear systems theory and nonlinear control system design, with a focus on advanced flight control systems and autonomous flight management systems for aerospace vehicles. In particular, he developed during his Ph. D. research a Differential Algebraic Spectral Theory (DAST) that generalizes the important concept of eigenvalues and eigenvectors for Linear Time-Invariant (LTI) system to Linear Time-Varying (LTV) systems.
Although he is electrical engineering in training, Dr. Zhu has become well-known in aerospace research community and the industry for advanced flight control and autonomous flight management systems, and he is an Associate Fellow of the American Institute of Aeronautics and Astronautics beginning January 2011. Based on the DAST, he advanced the Trajectory Linearization Control (TLC) and Trajectory Linearization Observer (TLO) techniques, which have been successfully applied to Reusable Launch Vehicles (RLV, i.e. Space Shuttle type of launch vehicles), Vertical Take-Off and Landing (VTOL) and fixed-wing aircraft flight control, aerodynamic flow control, mobile and flying robot control applications. To date he has published more than 100 papers in refereed journals and conference proceedings. In the past 20 years, he has been a Principal Investigator (PI) or Co-PI on research funded over $6M by NSF, AFOSR, AFRL, NASA, and ARMY SSDC. He led a 4-university team as the PI of a $4.4M NASA NRA8-30 research contract in 2001 from NASA/MSFC through national competition on Autonomous Flight Management (AFM) and Integrated Guidance and Control (IG&C) system for the Second-Generation Reusable Launch Vehicle (2GRLV) under the Space Launch Initiative (SLI) Program (with an additional $5M pending Cycle II contract that did not proceed due to SLI Program cancellation by NASA). That contract was the only AFM-IG&C algorithm development contract within the SLI Program and one of the only two contracts awarded to universities (the other one was a $40K contract). As the 2GRLV Program transitioned into the Orbital Space Plane (OSP) Program in 2003, Dr. Zhu was subcontracted by Lockheed Martin to perform flight control system design for their OSP vehicle until that program was canceled by NASA due to program direction change. In 2004, he was awarded an $800K subcontract from Boeing’s $32M contract with NASA on autonomous flight control for Boeing’s planetary landing vehicle for NASA’s Human and Robotics Technology (H&RT) Program, although Boeing’s contract was soon cancelled along with all 80 H&RT contracts by NASA Headquarters due to program funding constraints.
Dr. Zhu was the PI on the OHIO Team of another multi-university research led by University of Cincinnati on active flow control supported by a $400K grant from the Dayton Area Graduate Studies Institute and the Air Force Research Laboratory (DAGSI/AFRL) from 2002-2004, and was awarded a National Research Council/Air Force Office of Scientific Research Summer Faculty Fellowship for 2002 on active flow control research. He was funded by DAGSI/AFRL for $150K from 2005-2008 to develop a TLC based flight control systems for a conceptual hypersonic sramjet aircraft. From 2006-2009, he was awarded a $150K grant by the AFRL/RW Campus Challenge 3 national competition to develop a multi-modal platform for future munitions called Aerial Robotic Transformer, and the OHIO team was the runner-up of the two finalists (the other was Georgia Tech Aerospace Engineering Department). From 2002-2005 he led OHIO student teams to enter NASA Personal Air Vehicle (PAV, roadable aircraft or flying cars) student design competitions, and won three Honorable Mentions, one Third Prize and one Second Prize for their evolving multi-modal VTOL roadable aircraft (or flying car) concept called the Aeromobile.
Most of Dr. Zhu's graduate students are employed by major aerospace companies, such as Raytheon, Boeing, Lockheed Martin, GE Aircraft Engines, Orbital Science, and United Space Alliance, etc. Dr. Zhu has also consulted for many aerospace and advanced technology companies such as Cornerstone Research Group, Inc., Orbital Research, Inc., Advanced Research Technology, Corp., Signal Processing, Inc., Parker Hannifin Corporation Aircraft Wheel & Brake Division, and Universal Space Lines, LLC, etc.
Dr. Zhu has diverse interests and experiences beyond his major research areas in electrical engineering and aerospace applications. other than his Ph. D. degree in Electrical Engineering, Dr. Zhu also holds an MA degree in Mathematics and his MA thesis was published as two papers in the prestigious mathematical journal Linear Algebra and Its Applications (LAIA). His Ph. D. dissertation was also published as two papers in the prestigious mathematical journals LAIA and SIAM Journal on Control and Optimization. He is currently in collaboration with an OHIO Psychology Professor as a Co-PI on a $408K NSF grant entitled " “Modeling the Underlying Dynamic Processes in Motivation and Decision Making: A Parsimonious Self-Regulatory Approach” (NSF Grant No. SES-0851764).
Dr. Zhu has collaborations with many universities in China. Since 1994 He has been invited to give talks at the School of Automation and Electrical Engineering of Dalian Institute of Systems and Control, the Shenyang University of Technology, the Research Institute of Automatic Control (RIAC) of the Northeastern University, the School of Electronic Information and Control Engineering of the Beijing Polytechnic University, The School of Automation Science and Electrical Engineering and Institute of Robotics Research at the Beihang University (formerly the Beijing University of Aeronautics and Astronautics), Shanghai Jiaotong University, the Institute of System Sciences of Chinese Academy of Sciences. Dr. Zhu is currently collaborating with the Robotics Research Institute of the BeihangUniversity (formerly the Beijing University of Aeronautics and Astronautics) under a Chinese Natural Science Foundation (CNSF) on a multi-modal flying robot.
Dr. Zhu received the NSF Research Initiation Award in 1991. He was an AFOSR Summer Faculty Associate in 1995, a NASA Summer Research Fellow in 1999 and 2008, and a National Research Council/AFRL Summer Research Fellow in 2002 and 2005. Dr. Zhu is an Associate Fellow of AIAA and Senior Member of IEEE. He was a Technical Associate Editor of the Control Systems Magazine from 1996-1997, an Associate Editor of the IEEE Control System Society (CSS) Conference Editorial Board (CEB) from 1994-1997. He was the 34th CDC Program Committee Vice-Chairman for Short Papers, and the General Chair for the 28th IEEE Southeastern Symposium on System Theory (SSST). He was the Chairman/Editor of the IEEE CSS CEB and a member of the IEEE CSS Conference Activities Board from 1998-2001, and an Elected Member of the IEEE CSS Board of Governors from 2001-2003.
朱建潮教授简历
朱建潮教授1976年毕业于原北京工业大学工业自动化系。毕业后在北工大任教六年后于1982年赴美在亚拉巴马大学亨茨威尔分校（University of Alabama at Huntsville，UAH）读研，于1984，1986，1989年分别获得电机硕士，数学硕士，电机博士学位。取得博士学位后，他在UAH作了一年博士后，于1990年至2000年任教于路易斯安娜州立大学电机与计算机工程系，2000年至今任终身教授于俄亥俄大学电机与计算机科学系。朱教授的科研领域包括非线性（时变）系统控制理论，尤其在线性时变系统微分代数谱理论及轨迹线性化控制与观测方法有独到建树。在控制工程应用方面，朱教授的工作和贡献包括轨迹线性化飞行控制和机器人控制，曾于2001年主持过美航空航天局资助的第二代航天飞机的飞控系统研制开发工作（440万美元）。他还主持过20多项美国自然科学基金会，航空航天局及空军科学研究实验室的科研项目，累计科研经费数百万美元,，并与北京航空航天大学合作一项中国自然科学基金会飞行机器人科研项目。朱教授是AIAA副院士以及IEEE高级会员，共有各种学术期刊与会议论文上百篇。