Dynamics and Control of a Self-Reconfiguring Sphere Leading to the Design of a Spherical Mobile Robot

本研究计画设计与发展一种独特的球形移动的机器人，它具有球形外骨骼、内部自推进机制以及各种运动控制与侦察用的感测器。 机器人系统的独特功能包括其可伸缩的摄像机，可伸缩的机械手和伸缩四肢。当机器人静止时，手臂和肢体展开用于操纵和支撑，并且在机器人恢复其运动之前缩回。该机器人能够执行快速机动，并相对轻松地在粗糙的地形上移动。在球形机器人系统的发展过程中，在动力学，控制和机械系统的设计领域的三个基本问题得到解决。第一个问题涉及非完整系统的非线性反馈控制策略的发展，主要应用于滚动球。一个平滑的和时不变的控制器将被开发用于球的重构。尽管在非完整控制系统中取得了重大进展，但滚动球的重构仍然是一个悬而未决的问题。本研究的第二个问题是设计球体自推进的内部机构，并构造机构有效运行的闭环控制器。该机制提供了球体的能力，加速，以恒定的速度移动，或伺服在一个点。最后一个问题涉及到球形移动的机器人的发展，这是期望通过传感和控制之间的协调来实现自主性。 本课题涉及桁架结构的设计、传感器的选择和布置，以及通过上述两种控制器的集成来设计整个控制系统。非完整控制策略，开发作为本研究的一部分，被纳入先进控制系统课程，在密歇根州立大学机械工程系提供。内部机制为自推进的领域和球形移动的机器人的设计被用作动机的例子，在一些研究生和本科生课程的设计，结构，力学和控制。

This research project deals with the design and development of a unique spherical mobile robot having a spherical exo- skeleton, an internal mechanism for self-propulsion, and a variety of sensors for motion control and reconnaissance. Unique Features of the robotic system include its retractable camera, retractable manipulators, and telescopic limbs. The arms and limbs are deployed for manipulation and support when the robot is at rest and retracted before the robot resumes its motion. The robot is able to perform rapid maneuvers and move over rough terrain with relative ease. In the process of development of the spherical robotic system, three fundamental problems in the areas of dynamics, control, and design of mechanical systems are addressed. The first problem relates to the development of a nonlinear feedback control strategy for nonholonimic systems with primary application to the rolling sphere. A smooth and time- invariant controller will be developed for the reconfiguration of the sphere. Despite significant progress in nonholonomic control systems, the reconfiguration of the rolling sphere is still an open problem. The second problem of this research is to design an internal mechanism for self- propulsion of the sphere and to construct a closed loop controller for the effective operation of the mechanism. The mechanism provides the sphere with the capability to accelerate, move with constant velocity, or servo at a point. The final problem relates to the development of the spherical mobile robot, which is expected to achieve autonomy thorough coordination between sensing and control. This problem deals with design of the truss, choice and placement of sensors, and design f the overall control system through integration of the two controllers mentioned above. The nonholonomic control strategy, developed as a part of this research, is incorporated in the Advanced Control Systems course, offered in the Department of Mechanical Engineering at Michigan State University. The internal mechanism for self-propulsion of the sphere and the design of the spherical mobile robot are used as motivational examples in a number of graduate and undergraduate courses in design, structures, mechanics, and controls.