在国际项目管理中心资助下，应航天学院卫星技术研究所王峰教授的邀请，瑞尔森大学航空航天工程系（Department of Aerospace Engineering, Ryerson University）教授Krishna D. Kumar即将于2019年7月26日-2019年7月29日访问我校。访问期间将在我校开展学术报告。欢迎感兴趣的老师和同学参加。
讲座时间：7月27号，9:00-11:00
讲座地点：活动中心416
讲座题目：Spacecraft Dynamics and Control: Evolution and Current Challenges
讲座内容：This lecture will review the evolution of dynamics and control of spacecraft since the space era began with the launch of Sputnik in 1957. Early satellites typically weighted in the range of 100 kg had simple functionalities resulting in simple on-board control systems. In the 80's and 90's, the trend moved towards larger and more complex spacecraft weighing 1,000 kg to 10,000 kg with advanced on-board control systems. In the last two decades, with advances in miniaturization, small satellites such as nanosatellites, picosatellites and femtosatellites have been designed andsome of them using simple to advanced control systems have been launched as well. In addition, spacecraft formation flying has been considered as an enabling technology for future space missions. Several propellant-free or passive methods and active methods for spacecraft control and maneuvering have been proposed in the literature; in the case of spacecraft orbital maneuvering, these methods are mainly based on thrusters, aerodynamic forces, solar radiation pressure, magnetic forces, and tethers. On the other hand, the methods for spacecraft attitude control and maneuver include reaction wheels/control moment gyros, thrusters, fluid rings, solar radiation pressure, aerodynamic forces, magnetic torquers, tethers, manipulators, MEMS devices, and movable masses.The controllers for spacecraft orbit and attitude maneuvering have been designed using linear control techniques as well as nonlinear control techniques such as linear quadratic regulator, Lyapunov-based control, feedback linearization control, sliding mode control or variable structure control, adaptive control, intelligent control (includes neural networks, fuzzy logic, and genetic programming), and combination of these. In addition to the fully actuated spacecraft, partial or intermittent failures of actuators as well as complete failures of some actuators i.e., the underactuated systems have also been examined. The feasibility of all these methods/techniques is established, in general, using stability analysis based on Lyapunov theory, numerical simulations, hardware-in-loop (HIL) simulations, and flight demonstrations. The evolution of all these methods, their current status and challenges associated with them with a focus on my research work will be briefly presented along with future direction of research on spacecraft dynamics and control.
