A robotic platform for mobile manipulation needs to satisfy two contradicting requirements for many real-world applications: A compact base is required to navigate through cluttered indoor environments, while the support needs to be large enough to prevent tumbling or tip over, especially during fast manipulation operations with heavy payloads or forceful interaction with the environment. This paper proposes a novel robot design that fulfills both requirements through a versatile footprint. It can reconfigure its footprint to a narrow configuration when navigating through tight spaces and to a wide stance when manipulating heavy objects. Furthermore, its triangular configuration allows for high-precision tasks on uneven ground by preventing support switches. A model predictive control strategy is presented that unifies planning and control for simultaneous navigation, reconfiguration, and manipulation. It converts task-space goals into whole-body motion plans for the new robot. The proposed design has been tested extensively with a hardware prototype. The footprint reconfiguration allows to almost completely remove manipulation-induced vibrations. The control strategy proves effective in both lab experiment and during a real-world construction task.

翻译：面向移动操作任务的机器人平台需同时满足两个相互矛盾的现实需求：紧凑型底座设计便于在拥挤的室内环境导航，而支撑结构需足够宽大以防止倾倒或翻覆，尤其在重载荷快速操作或与环境强力交互时。本文提出一种通过可变足迹满足上述需求的创新机器人设计：其支撑面可在窄幅构型（适应狭窄空间导航）与宽幅构型（适应重物操作）间自主重构。此外，三角构型通过防止支撑切换机制，能够在非平坦地面完成高精度操作任务。本文提出基于模型预测控制的统一规划与控制策略，实现导航、重构与操作的协同控制，将任务空间目标转换至新机器人的全身运动规划。该设计已通过硬件样机完成充分测试，足迹重构功能可近乎完全消除操作引发的振动，所提控制策略在实验室环境与真实建筑作业中均验证有效。