Control of Micro Aerial Vehicles under Aerodynamic and Physical Contact Interactions

该项目的目标是让四旋翼和其他类似的小型飞行旋翼机更安全、更容易飞行。这些车辆的娱乐和商业用途最近都很受欢迎。然而，对潜在破坏性碰撞的安全担忧限制了它们在人附近或近距离编队的部署，而且目前车辆控制的最新水平不足以满足在工业工厂、森林和洞穴等复杂结构内飞行的潜在应用。具体地说，该项目将导致以下创新：通过新的模型更好地了解环境和飞行器之间的空气动力学相互作用；创建一个封闭飞行器并同时充当减震器和新型“触摸”传感器的“智能笼子”；以及推导出新的控制策略，以利用新的特征来提高性能和操纵性。总而言之，这些创新将使小型车辆不太可能造成意外损害，适合在洞穴等极端环境中使用，并且更容易驾驶。这将反过来允许在新的工业监测和搜救应用中使用这些车辆，从而将这些平台的好处带给更多的社会阶层。该项目的技术目标将建立在新的四旋翼气动模型上，通过模拟和实验评估相结合的方式构建。这些模型预测由于每个转子与其他转子以及与地面、墙壁和天花板等邻近表面的气动相互作用而产生的力和扭矩。一个智能笼子环绕着车辆，由一个刚性外壳和一个底座组成，外壳防止四旋翼接触环境中的物体，底座刚性连接到四旋翼上。笼子和底座通过一个用来吸收冲击的弹簧系统连接在一起。底座包括传感器来测量外壳的相对位移，从而允许部分重建任何撞击动力学。基于压缩理论在黎曼流形上的一种新的应用，提出了新的控制策略。这些策略产生的几何控制器不会出现奇点，具有全局指数收敛保证，并且可以自动调整以获得最佳性能。结果将在仿真和实验中得到验证。

The goal of this project is to make quadrotors and other similar small-scale flying rotorcraft safer and easier to fly. Both recreational and commercial use of these vehicles has recently surged in popularity. However, safety concerns about potentially damaging collisions limit their deployment near people or in close formation, and the current state of the art in vehicle control is insufficient for potential applications involving flight inside of complicated structures such as industrial plants, forests and caves. Specifically, this project will lead to the following innovations: better understanding of the aerodynamic interactions between the environment and the flying vehicle through novel models; creation of a "smart cage" that encloses the vehicle and acts as both a shock-absorber and as a novel type of "touch" sensor; and the derivation of new control strategies to take advantage of the new features to improve performances and ease of maneuvering. Together, these innovations will make small-scale vehicles less likely to cause unintended damage, suitable for use in extreme environments such as caves, and more easily piloted. This will allow in turn the use of these vehicles in new industrial monitoring and search-and-rescue applications, thus bringing the benefits of these platforms to larger segments of society. The technical goals of this project will build on new models of quadrotor aerodynamic, constructed through a combination of simulation and experimental evaluation. These models predict forces and torques due to the aerodynamic interactions of each rotor with the other rotors, as well as with nearby surfaces, such as ground, walls, and ceilings. A "smart cage" surrounds the vehicle, composed of a rigid outer shell to prevent the quadrotor from contacting objects in the environment, and a base, which is rigidly attached to the quadrotor. The cage and the base connect together through a system of springs that are used to absorb impacts. The base includes sensors to measure the relative displacement of the outer shell, thus allowing a partial reconstruction of any impact dynamics. New control strategies are formulated, based on a novel application of contraction theory to Riemannian manifolds. These strategies produce geometric controllers that do not suffer from singularities, that have global exponential convergence guarantees, and that can be automatically tuned to obtain optimal performance. The results will be validated in both simulations and experiments.