In this letter, we propose a multi-contact locomotion planning framework for a humanoid robot to traverse complex environments utilizing bilateral contact forces with reasonable computational time. We hypothesize that a bilateral contact can be approximated by a pair of surface contacts, and expand the static CoM feasible region by this assumption, which we define as bSCFR. This assumption enables us to project centroidal statics with bilateral contact forces to a constraint on whole-body kinematics. Then, we formulate the whole-body inverse kinematics problem for all the discretized frames in the target contact transition as one optimization problem with bSCFR and CoM regularization, which can find feasible whole-body configurations while considering both kinematics and statics. After solving whole-body inverse kinematics, the contact forces are computed based on the centroidal statics, where appropriate bilateral contact forces are automatically generated according to the resulting CoM positions. We experimentally confirm that our proposed framework enabled HRP-5P to traverse steep stairs utilizing bilateral contact forces in the real world, and conclude that it expands the multi-contact locomotion capability of a humanoid robot.

中文翻译：

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考虑接触过渡期间运动学和静力学的具有双边接触力的多接触运动规划


在这封信中，我们提出了一种多接触运动规划框架，供人形机器人利用双边接触力和合理的计算时间穿越复杂的环境。我们假设双边接触可以用一对表面接触来近似，并通过这个假设扩展静态CoM可行区域，我们将其定义为bSCFR。这一假设使我们能够将具有双边接触力的质心静力学投影到对全身运动学的约束。然后，我们将目标接触过渡中所有离散框架的全身逆运动学问题公式化为一个具有 bSCFR 和 CoM 正则化的优化问题，它可以在考虑运动学和静力学的同时找到可行的全身配置。求解全身逆运动学后，根据质心静力学计算接触力，根据得到的 CoM 位置自动生成适当的双边接触力。我们通过实验证实，我们提出的框架使 HRP-5P 能够利用现实世界中的双边接触力穿过陡峭的楼梯，并得出结论，它扩展了人形机器人的多接触运动能力。