This paper presents a distributed inverse dynamics controller (DIDC) for quadruped robots that addresses the limitations of existing reactive controllers: simplified dynamical models, the inability to handle exact friction cone constraints, and the high computational requirements of whole-body controllers. Current methods either ignore friction constraints entirely or use linear approximations, leading to potential slip and instability, while comprehensive whole-body controllers demand significant computational resources. Our approach uses full rigid-body dynamics and enforces exact friction cone constraints through a novel geometric optimization-based solver. DIDC combines the required generalized forces corresponding to the actuated and unactuated spaces by projecting them onto the actuated space while satisfying the physical constraints and maintaining orthogonality between the base and joint tracking objectives. Experimental validation shows that our approach reduces foot slippage, improves orientation tracking, and converges at least two times faster than existing reactive controllers with generic QP-based implementations. The controller enables stable omnidirectional trotting at various speeds and consumes less power than comparable methods while running efficiently on embedded processors.

翻译：本文提出一种用于四足机器人的分布式逆动力学控制器，旨在解决现有反应式控制器的局限性：简化的动力学模型、无法处理精确摩擦锥约束，以及全身控制器的高计算需求。现有方法要么完全忽略摩擦约束，要么采用线性近似，可能导致打滑和失稳；而全面的全身控制器则需要大量计算资源。本方法采用完整的刚体动力学模型，并通过一种基于几何优化的新型求解器强制执行精确的摩擦锥约束。DIDC 通过将对应于驱动空间与非驱动空间的所需广义力投影至驱动空间，在满足物理约束的同时保持基座与关节跟踪目标间的正交性，从而实现两者的融合。实验验证表明，相较于采用通用 QP 实现的现有反应式控制器，本方法能减少足端打滑、改善姿态跟踪性能，且收敛速度至少提升两倍。该控制器支持多速度下的稳定全向小跑步态，在嵌入式处理器上高效运行的同时，功耗低于同类方法。