本研究目標為使一具有雙致動器及平坦狀腳底板的單足機器人完成穩定跳躍，並建立一套完整的控制策略。為了仿照人類跳躍的動作，機器人在起跳前會經歷特殊的欠致動狀態，亦即其腳底會繞著未致動的腳趾旋轉，此狀態可使跳躍的距離更遠也使動作更加自然與流暢。論文中首先建立一個三連桿單足機器人之運動模型以利分析動態，藉著參考文獻的控制法並進一步套用於此模型。並透過質量與長度的機構參數設計，使複雜的零點動態簡化成單擺動態進而起跳。而後從空中，利用運動學分析決定控制目標以及著地閉迴路控制完成一跳躍週期之控制策略。最後模擬驗證機器人可以以論文中提出的跳躍策略達成欠致動跳躍，並且可以透過調整其中參數來改變其控制性能。

In this paper, the purpose is to establish a control strategy for an under-actuated one-legged hopping robot constructed from three links with two actuators and flat-shaped foot. To act like a human, the robot will go through an under-actuated phase in which the foot rotates around the under-actuated toe on the ground before taking off. By this special feature, it can perform human-like hops with longer hopping distance than a fully actuated robot. First we derive the robot system’s dynamics, and implement the control method from reference. By choosing particular mass and length parameters, zero dynamics turn into a simple pendulum motion, which causes the robot to hop. Next, kinematics are analyzed to design the control target during flight phase. Finally, close-loop control is used to simulate the center of mass act as a spring damper system to stabilize the robot in the landing phase and complete the hop cycle. In conclusion, the simulation results demonstrate that it can achieve under-actuated hopping by the control strategy, and performance can be changed by modifying the control parameters.

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