Niu Hao, Zhao Xin, Jin Hongzhe, Zhang Xiuli
School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044, China.
The State Key Laboratory of Robotics and System, School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China.
Biomimetics (Basel). 2024 Dec 16;9(12):766. doi: 10.3390/biomimetics9120766.
Humanoid robots are becoming a global research focus. Due to the limitations of bipedal walking technology, mobile humanoid robots equipped with a wheeled chassis and dual arms have emerged as the most suitable configuration for performing complex tasks in factory or home environments. To address the high redundancy issue arising from the wheeled chassis and dual-arm design of mobile humanoid robots, this study proposes a whole-body coordinated motion control algorithm based on arm potential energy optimization. By constructing a gravity potential energy model for the arms and a virtual torsional spring elastic potential energy model with the shoulder-wrist line as the rotation axis, we establish an optimization index function for the arms. A neural network with variable stiffness is introduced to fit the virtual torsional spring, representing the stiffness variation trend of the human arm. Additionally, a posture mapping method is employed to map the human arm potential energy model to the robot, enabling realistic humanoid movements. Combining task-space and joint-space planning algorithms, we designed experiments for single-arm manipulation, independent object retrieval, and dual-arm carrying in a simulation of a 23-degree-of-freedom mobile humanoid robot. The results validate the effectiveness of this approach, demonstrating smooth motion, the ability to maintain a low potential energy state, and conformity to the operational characteristics of the human arm.
人形机器人正成为全球研究热点。由于双足行走技术的局限性,配备轮式底盘和双臂的移动人形机器人已成为在工厂或家庭环境中执行复杂任务的最合适配置。为解决移动人形机器人轮式底盘和双臂设计带来的高冗余问题,本研究提出一种基于手臂势能优化的全身协调运动控制算法。通过构建手臂的重力势能模型以及以肩-腕线为旋转轴的虚拟扭转弹簧弹性势能模型,我们建立了手臂的优化指标函数。引入具有可变刚度的神经网络来拟合虚拟扭转弹簧,以表征人类手臂的刚度变化趋势。此外,采用姿态映射方法将人类手臂势能模型映射到机器人上,实现逼真的人形运动。结合任务空间和关节空间规划算法,我们针对一个23自由度的移动人形机器人在模拟环境中进行了单臂操作、独立物体检索和双臂搬运实验。结果验证了该方法的有效性,展示了平滑的运动、保持低势能状态的能力以及符合人类手臂操作特性。