本研究主要發展輪式倒單擺機器人相關技術，包含訊號融合、 平衡控制與全身姿態控制。在訊號融合方面結合雙慣性感測器的量測資訊，提出新穎的俯仰角角度估測理論。此估測理論的主要目標為消除運動加速度對倒單擺機器人俯仰角估測的影響。在平衡控制方面，提出對倒單擺質心高度變化具強健性的控制理論。此控制理論的回授控制矩陣是透由對一系列線性矩陣不等式求解得到，使得Lyapunov穩定定理得以於線性變參數(LPV)模型實現。於全身姿態控制方面，提出兩種控制理論:質心位置控制理論與側傾控制理論。質心位置控制理論旨在使倒單擺機器人質心隨著參考質心位置軌跡移動同時維持身體姿態直立。質心位置控制器的設計是透過建構倒單擺機器人三連桿模型、關節角速度與質心速度之間的逆向微分運動學關係以及PI控制來達成。另一方面，側傾控制理論旨在調節倒單擺機器人的側傾角使其到達期望角度。側傾控制理論的設計同樣採用PI控制，並透過建構足以描述側傾角與雙足關節角度之間關係的倒單擺機器人五連桿模型來完成。最後將訊號融合與控制方法施加於本實驗室建構的輪式倒單擺人型機器人，並利用模擬與實作驗證上述理論的可行性。

This thesis aims to develop systematic methodologies to perform sensor fusion, balancing control, and whole-body posture control on a humanoid wheel inverted pendulum (WIP) robot. For sensor fusion, a novel pitch angle estimator is proposed by merging the measurements for two IMU’s. Such an estimator is meant to eliminate the error caused by motion acceleration when estimating the pitch angle for feedback purposes. For the balancing control, a controller that provides robust stability to the variations of the CoM height is proposed. Its feedback gain matrix is computed by solving a set of linear matrix inequalities so that Lyapunov stability can be achieved on a linear parameter varying (LPV) model. For the whole-body posture control, it contains two controllers: the centroid controller and the roll angle controller. The objective of the centroid controller is to make the centroid follow a reference command while keeping the robot body in an upright position. The centroid controller is PI-based and is designed by constructing a three-link model and inverting the differential kinematic relationship between the joint velocities and the centroid velocities. On the other hand, the roll angle controller is to regulate the robot’s roll angle. It is also PI-based and is designed using a five-link model that describes the kinematic relations between the roll angle and the joint angles of the legs. The sensor fusion and control methods are implemented on a humanoid WIP robot built in-house. Simulations and experiments are conducted to validate the feasibility of the proposed approaches.

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