四足機器人腿部彈性結構評估與分析

本文旨在評估並聯彈簧致動器於四足機器人腿部機構中的應用效果，並探討不同運動週期與彈簧剛性變化對關節扭矩、功率與能量輸出需求的影響。基於拉格朗日方程式建立機構動力學模型，並以MATLAB進行模擬與分析。結果顯示，設計適當的彈簧剛性可有效降低膝關節輸出扭矩高達55 %，並於不同運動週期條件下，亦可達成20 %至50 %不等的功率降低，並使蹲下階段的能量輸出需求減少超過50 %。多目標優化結果指出，當運動週期為2秒時，最佳彈簧剛性為12241 N/m，展現出動態性能的優化效果。整體而言，並聯彈簧致動器具備分擔致動器負載與提升系統效能之潛力，適合做為未來四足機器人高效設計的重要策略。

This article aims to evaluate the effectiveness of parallel elastic actuators (PEA) applied to a leg structure of a quadruped robot, and to investigate the effects of varying joint motion periods and spring stiffness on knee joint torque, power, and energy output demands. A dynamic model is established based on the Lagrangian equation, and the model is analyzed using MATLAB simulations. The results indicate that with appropriately designed spring stiffness, the knee joint output torque can be reduced by up to 55 %, and power can be decreased by 20 % to 50 % across different motion cycles. Additionally, energy output during the crouching phase can be reduced by more than 50 %. Multi-objective optimization further revealed that when the motion cycle is 2 seconds, the optimal spring stiffness is 12241 N/m, demonstrating an effective balance of dynamic performance. Overall, PEAs show great potential in reducing actuator load and enhancing system efficiency, making them a promising strategy for high-performance quadruped robot design.