- 期刊
Effects of Ground Compliance on Bipedal Robot Walking Dynamic Property
地面柔性對雙足機器人步行動力學特性的影響
摘要
本文基於剛柔耦合模型，探討雙足步行機器人在柔性地面行走過程中動力學特性的變化。首先，建立剛性機器人與柔性地面之間的桿式耦合動力學模型；然後，根據ZMP（零力矩點）穩定判據規劃機器人在剛性地面行走的離線步態；其次，在ANSYS中建立柔性地面的有限元模型，導入ADAMS建立機器人－地面剛柔耦合模型；最後，在仿真環境中探究地面柔性對機器人動力學特性的影響。仿真結果顯示：1）隨著地面柔性的降低，機器人質心的前向位移下降了2.69%；2）左右足底的碰撞力分別增加了28.46%和24.33%，但是平均接觸力分別減小了11.71%和9.69%；3）左右踝關節的平均轉矩分別降低了13.24%和14.16%。與剛性地面相比，隨著地面柔性的提高，相應減少機器人步長能達到等效前向行走；同時，機器人關節需要選用輸出轉矩更大的驅動馬達，從而造成能耗增加。
關鍵字
無資料並列摘要
This paper investigates the variations of bipedal robot's dynamic property walking on compliant ground based on rigid-compliant coupling model. Firstly, the coupling dynamic rod model between a rigid bipedal robot and compliant ground is established. Next, the robot's off-line gait on rigid ground is planned based on ZMP (zero moment point) criterion. Then, the compliant ground model is built in ANSYS for modeling the coupling virtual prototype between robot and ground in ADAMS. Finally, simulations are performed to reveal the effect of ground compliance on bipedal robot's dynamic property. The simulation results indicate that: 1) as the ground compliance decreases, the displacement of COM (center of mass) along axis X decreases by 2.69%. 2) the left sole and right sole impact forces increase by 28.46% and 24.33%, respectively, while the average contact forces decrease by 11.71% and 9.69%. 3) the average torques of left ankle joint and right ankle joint decrease by 13.24% and 14.16%. Compared with rigid ground, if the bipedal robot walks on ground with higher compliance, the step length of robot should be decreased to obtain the equivalent result. In the meantime, the driving motor with grater output torque will be chosen, which might lead to more energy consumption.