本研究旨在建構新一代雙足機器人系統，整體內容涵蓋機構設計、虛擬環境建置與底層控制三大面向。機構上，透過四連桿及特殊連桿組(2-RSU-1-U)構建並聯式機構於膝關節及踝關節，使系統動態近似於倒單擺系統，從而利於以簡化模型實現整體控制，更採用可背向驅動的致動器於各關節，以便藉由扭矩控制實現互動行為。虛擬環境部分，利用ROS2結合Gazebo建構模擬環境，進行物理環境的模擬驗證，並使用開源函示庫(Pinocchio )進行動力學參數的計算。底層控制上，針對不同支撐狀態構建控制架構。雙支撐狀態下，透過運動學調控骨盆與腳底的相對姿態，實現穩定站立與骨盆軌跡追蹤；在單支撐狀態下，鑒於機構的優勢，故引入混成控制架構，將機器人等效為角動量線性倒單擺模型，並通過設計不同的踝關節控制器，實現單腳平衡及質心軌跡追蹤。經由驗證，目前機器人實體具備低下肢轉動慣量及實現高頻寬控制的特性，並已成功利用虛擬環境實現底層控制的動態模擬。

This research aims to develop a next-generation bipedal robot system, covering three main aspects: mechanical design, virtual environment construction, and low-level control.
Mechanically, the system features a parallel mechanism at the knee and ankle joints, constructed using a four-bar linkage and a special link assembly (2-RSU-1-U). This setup approximates the dynamics of an inverted pendulum system, facilitating overall control through simplified models. The robot employs backdrivable actuators at each joint, allowing for interactive behavior through torque control. In terms of the virtual environment, ROS2 combined with Gazebo is used to construct the simulation environment for physical environment validation, while the open-source library Pinocchio is utilized for calculating dynamic parameters. For low-level control, a control framework is developed for different support states. In the double-support state, kinematic adjustments are made to the relative posture of the pelvis and foot to achieve stable standing and pelvis trajectory tracking. In the single-support state, taking advantage of the mechanism's design, a hybrid control framework is introduced, modeling the robot as an angular momentum linear inverted pendulum. Different ankle joint controllers are designed to achieve single-leg balance and centroid trajectory tracking.
Verification shows that the physical robot features low lower limb momentum of inertia and high-bandwidth control capabilities, and dynamic simulation of low-level control has been successfully achieved using the virtual environment.

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