CAREER: Structure and Control of Systems with Contact Uncertainty

该学院早期职业发展（CAREER）补助金将创造新的方法来理解和控制行走，跳跃或抓取的机器人。具体来说，该项目将研究反复与地面或其他表面接触和断开接触的机器人。规划和控制涉及接触的运动是特别具有挑战性的，因为例如两个表面或接触发生的点之间的摩擦的非常小的变化可能导致机器人的整体运动的大的变化。例如，机器人手接触工具的位置的微小变化可能导致工具从机器人的抓握中滑落。或者，机器人在岩石地面上放置脚的微小差异可能会导致机器人绊倒和摔倒。当机器人的工作空间得到仔细的监控和维护时，它们是最成功的。为了让机器人在非结构化和不可预测的现实世界中同样成功，需要新的运动规划和控制方法，例如本项目将开发的方法。这些新功能有望在从家庭医疗保健到环境监测再到制造业的应用中获益。该项目还包括K-12，本科和研究生教育的机器人活动。该项目将建模和分析接触条件不确定的系统结构。特别是，这项工作考虑了不确定的接触时间和事件序列的局部稳定性，以及系统的全局拓扑结构。该项目将通过将收缩或收敛的概念扩展到不连续接触系统以及寻找持久的拓扑特征来发现预测成功行为的动力学和接触条件的特性。然后，本项目的第二部分将使用这些属性来找到新的控制生成策略，这些策略对计划的接触事件的时间的不确定性具有鲁棒性，并且预测并可能避免计划外的接触事件。虽然许多特设的解决方案已经研究了不同的设置，这项研究将统一和扩展这些点的解决方案，利用这些共同的结构属性。其结果将是一套生成控制器的方法，当接触模式发生意外变化时，例如当脚在表面上磨损或滑动时，这些控制器可以避免问题行为，但仍然允许丰富的变化接触条件。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This Faculty Early Career Development (CAREER) grant will create new ways to understand and control robots that walk, jump, or grasp. Specifically, the project will study robots that repeatedly make and break contact with the ground or some other surface. Planning and controlling motion involving contact is particularly challenging, because very small changes in, for example, the friction between the two surfaces or the points at which the contact occurs, may cause large changes in the robot's overall motion. For example, small changes in where a robot hand touches a tool may cause the tool to slip from the robot's grasp. Or small differences in where a robot places its foot on rocky ground may cause the robot to trip and fall. Robots are most successful when their workspace is carefully monitored and maintained. For robots to be equally successful in unstructured and unpredictable real-world settings requires new motion planning and control methods, such as this project will develop. These new capabilities promise benefits in applications ranging from home healthcare, to environmental monitoring, to manufacturing. The project also features robot activities for K-12, undergraduate, and graduate education.This project will model and analyze the structure of systems that have uncertainty in their contact conditions. In particular, this work considers both local stability properties around uncertain contact timing and event sequences, as well as the global topological structure of the system. This project will discover properties of the dynamics and contact conditions that predict successful behaviors by extending notions of contraction or convergence to discontinuous contact systems as well as finding persistent topological features. The second part of this project will then use these properties to find new control generation strategies that are robust to uncertainty in the timing of planned contact events as well as anticipate and possibly avoid unplanned contact events. While many ad hoc solutions have been researched for different settings, this research will unify and extend these point solutions by leveraging these common structural properties. The result will be a set of methods for generating controllers that avoid problematic behavior when contact modes change unexpectedly, for example when feet scuff or slip on a surface, but still allow for rich changing contact conditions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.