Adaptive Chain Observers for Controlling Cooperating Clusters of Nonlinear Delayed-Output Mechanical Systems

自适应链观测器控制合作集群的非线性延迟输出机械systemsAbstract：该建议结合了基础研究与硬件在环实验，以产生和验证新的控制方法，合作集群的不确定性机械系统。这项研究的独特之处来自于我们明确考虑的时间延迟特性，在现实的低带宽车对车通信网络是不可或缺的。研究计划的理论部分侧重于通过领导者-追随者层次结构指挥的非线性动力系统的合作集群。领导者控制器通过跟踪由非线性参考模型生成的参考轨迹来执行车队的绝对定位和定向。跟随器控制器依赖于从引导器接收到的时间延迟的参考轨迹信号，以确保维持期望的“编队几何形状”。参数的不确定性内的各个模型的追随者需要设计的自适应控制器，利用当前可用的本地状态信息。充分考虑到通信延迟的影响，我们提出了一个创新的链观测器结构板载每个追随者的发展，其目标将是“估计”在闭环意义上的非线性参考模型的领导者的无延迟的瞬时状态。这种链结构将进一步加强新的自适应控制解决方案，将来自非线性重新参数化技术最近提出的。自适应控制框架，包括链观测器，避免了过度参数化，并提供了某些独特的流形吸引性属性，显着提高闭环性能。该建议的实验部分将在戈达德航天飞行中心的分布式航天器编队飞行试验台设施内实施和评估所有理论。

Adaptive Chain Observers for Controlling Cooperating Clusters of Nonlinear Delayed-Output Mechanical SystemsAbstract:This proposal combines basic research with hardware-in-the-loop experimentation to generate and validate new control methodologies for cooperating clusters of uncertain mechanical systems. Uniqueness of this study arises from our explicit consideration of time-delay characteristics that are integral within realistic low-bandwidth vehicle-to-vehicle communication networks. Theoretical part of the research plan focuses upon cooperating clusters of nonlinear dynamical systems that are commanded through a leader-follower hierarchy. The leader controller enforces absolute positioning and orientation of the fleet by tracking reference trajectories generated by a nonlinear reference model. The follower controllers rely upon time-delayed reference trajectory signals received from the leader to ensure that the desired "formation geometry" is maintained. Parameter uncertainty within the respective models of the followers necessitates the design of adaptive controllers that utilize currently available local state information. Duly taking the effects of communication delay into consideration, we propose the development of an innovative chain-observer structure onboard each follower whose objective would be to "estimate" in a closed-loop sense the undelayed instantaneous state of the nonlinear reference model of the leader. This chain structure would be further strengthened by new classes of adaptive control solutions that will be derived from nonlinear re-parameterization techniques recently given by the proposer. The adaptive control framework including the chain-observer avoids over-parameterization and provides certain unique manifold attractivity properties that significantly boost the closed-loop performance. The experimental component of this proposal will implement and evaluate all the theory within the distributed spacecraft formation flying testbed facility at the Goddard Space Flight Center.