Virtual Constraints: A New Paradigm for the Control of Motion

这个建议涉及的非线性动力系统的运动控制的一个新的范例的调查。运动控制问题涉及设计算法，使一个或多个动力系统表现出规定的行为。运动控制问题在工程的所有领域都有很多，包括多足机器人的运动，自主飞行器的飞行控制，以及陆地，空中和太空飞行器的编队控制。传统的运动控制方法对环境中的干扰和不确定性具有有限的鲁棒性，因此不足以解决新兴的应用，如多足机器人的运动和航天器编队的协调。在过去的十年中，出现了一种新的运动控制模式，它有可能克服传统方法的局限性，并可能实现新一代的运动控制算法。这种范式依赖于虚拟约束的概念，虚拟约束是对控制系统状态的约束，物理上不存在，但可以通过反馈控制来强制执行。虚拟约束的概念已被成功地用于诱导稳定的步行步态的机器人，但仍需要做大量的研究，使虚拟约束范式超越了步行运动，并成为普遍的，足以适用于大量的工程问题。该研究计划将为一类机械系统和自动驾驶车辆的虚拟约束系统理论奠定基础，并将研究其在卫星编队控制和机器人遥操作中的应用。本研究计划的最终目标是一套通用的工具来自动生成运动基元的集合。每个运动基元将与虚拟约束相关联，并且将对应于期望的行为。然后，不专业的用户将能够选择一系列运动基元来诱导动力系统中的复杂行为。这项研究计划的成果可能在机器人技术，航空航天工程和康复工程等领域具有相当大的实际意义。

This proposal concerns the investigation of a new paradigm for motion control in nonlinear dynamical systems. The motion control problem involves designing algorithms to make one or more dynamical systems exhibit a prescribed behaviour. Motion control problems abound in all areas of engineering, and include locomotion in multi-legged robots, flight control of autonomous aircrafts, and formation control of terrestrial, aerial, and space vehicles. The traditional motion control methodology has limited robustness against disturbances and uncertainties in the environment, and it is therefore inadequate to address emerging applications such as locomotion in multi-legged robots and coordination of spacecraft formations. In the last decade, a new paradigm for motion control has emerged which has the potential to overcome the limitations of traditional methods, and may enable a new generation of motion control algorithms. This paradigm relies on the concept of virtual constraint, a constraint on the states of a control system that does not physically exist, but can be enforced via feedback control. The notion of virtual constraint has been used with great success to induce stable walking gaits in biped robots, but much research remains to be done to make the virtual constraint paradigm go beyond biped locomotion, and become general enough to be applicable to a vast array of engineering problems. The proposed research program will lay the foundations for a systematic theory of virtual constraints for a class of mechanical systems and autonomous vehicles, and will investigate its applications to the control of satellite formations and robotic teleoperation. The ultimate goal of this research program is a set of general tools to automatically generate a collection of motion primitives. Each motion primitive will be associated with a virtual constraint, and will correspond to a desired behaviour. An inexpert user will then be able to select a sequence of motion primitives to induce complex behaviours in the dynamical system. The outcomes of this research program may have considerable practical implications in areas as diverse as robotics, aerospace engineering, and rehabilitation engineering.