輪腳複合機器人之動態步態與越障姿態調控

Dynamic Gait Generation and Posture Stabilization on Rough Terrain for a Leg-Wheel Transformable Robot

林紘生(Hung-Sheng Lin)

指導教授 ： 林沛群

國立臺灣大學/工學院/機械工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.10400

摘要

多足機器人的運動是近年非常熱門的課題，其中包括了以動物高速高效率的動態運動為藍圖的動態步態開發，以及以克服各種不同崎嶇障礙為目標的越障策略研究，希望能借此提升多足機器人的運動能力，讓機器人能在有限的能源限制底下跑得最遠，並具有克服路徑上各式障礙物的越障能力。在各式生物中又以四足動物的步態最為複雜，本研究的的主要目的在於為特殊型態的四足機器人平臺：輪足變換四足機器人TurboQuad，開發合適的動態步態以及靜態的越障策略。
本研究所使用的動態運動開發策略為Model-based的動態運動規劃及控制方法，以Rolling-SLIP模型為基礎，結合TurboQuad上原有的CPG（Central Pattern Generator）控制架構，使TurboQuad保有輪足變換及多足協調的能力，並根據TurboQuad的腳步幾何特性開發高速動態運動步態，本研究選用的動態步態為小跑步（trot）以及彈跳（pronk）步態，並以定性或定量實驗方法評估動態步態的開發成果。
除了動態步態開發之外，本研究亦致力於發展回饋控制架構，讓TurboQuad在慢速步行越障時能夠表現的更加穩定，在發展回授控制之前，本研究就原本的開迴路型軌跡做了優化，引入了Time clock的架構，將時間的概念帶入原有的CPG架構之中，讓相位調控的機制更加直觀，方便後續回饋控制的發展，並且調整了開迴路的軌跡生成方法，使其符合在平坦地面等速前進與身體等高移動的目標，並以實驗方法進行分析評估；此外，本研究為TurboQuad提供了力感測、地面高度回授及身體姿態回饋控制的可能性，並以定性或定量實驗方法檢驗地面高度回授及身體姿態回饋控制的表現。

關鍵字

仿生機器人 ； 輪腳複合平台 ； 四足機器人 ； 動態步態 ； 回授控制 ； 中樞模式產生器 ； 模型基礎控制

並列摘要

The motion of the multi-legged robots is one of the popular research topics in recent years. The researching field includes developing dynamic gaits basedd on animals’ locomotion for robots and strategy to overcome rough terrain and obstacles. These research can enable robots the ability to run further with limited energy supply and move agilely on all kinds of terrain. The quadraped in particular has the most complicated gaits in all kind of animals. The main purpose of this thesis is to develop suitable dynamic gaits and obstacle surmounting strategies for the specific quadraped robot TurboQuad using model-basedd motion planning and control method. On the premise of preserving the transformation between leg and wheel and multi-legged coordination, by combining the Rolling-SLIP model and the CPG (Central Pattern Generator) built in the TurboQuad the high speed dynamic gait is established basedd on the geometry characteristic of the legs. Experiments are conducted to verify the stability of the trotting and pronking dynamic gaits. Aside from the dynamic gaits development, this thesis also aims to enable the robots to overcome barriers on rough terrain more stably with feedback control. By introducing Time clock structure into the original CPG the phase modulation is more intuitive, which makes the feedback control development easier. The open-looped trajectory is optimized so that the robot can move with constant speed and keep the apex height the same on flat ground. TurboQuad is also equipped with force sensor, ground height detection and body posture sensor to feed in the feedback control. The effect of the feedback control is verified by experiments and the result is promising.

並列關鍵字

Bio-inspired robotics ； Leg-wheel hybrid platform ； Quadruped robot ； Dynamic gait ； Feedback control ； Central Pattern Generator ； Model-based control

參考文獻

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