Bing Zhenshan, Cheng Long, Chen Guang, Röhrbein Florian, Huang Kai, Knoll Alois
Fakultät für Informatik, Technische Universität München, Germany.
Bioinspir Biomim. 2017 Apr 4;12(3):035001. doi: 10.1088/1748-3190/aa644c.
Snake-like robots with 3D locomotion ability have significant advantages of adaptive travelling in diverse complex terrain over traditional legged or wheeled mobile robots. Despite numerous developed gaits, these snake-like robots suffer from unsmooth gait transitions by changing the locomotion speed, direction, and body shape, which would potentially cause undesired movement and abnormal torque. Hence, there exists a knowledge gap for snake-like robots to achieve autonomous locomotion. To address this problem, this paper presents the smooth slithering gait transition control based on a lightweight central pattern generator (CPG) model for snake-like robots. First, based on the convergence behavior of the gradient system, a lightweight CPG model with fast computing time was designed and compared with other widely adopted CPG models. Then, by reshaping the body into a more stable geometry, the slithering gait was modified, and studied based on the proposed CPG model, including the gait transition of locomotion speed, moving direction, and body shape. In contrast to sinusoid-based method, extensive simulations and prototype experiments finally demonstrated that smooth slithering gait transition can be effectively achieved using the proposed CPG-based control method without generating undesired locomotion and abnormal torque.
具有三维运动能力的蛇形机器人在适应各种复杂地形方面比传统的有腿或轮式移动机器人具有显著优势。尽管已经开发出了许多步态，但这些蛇形机器人在改变运动速度、方向和身体形状时，步态转换不顺畅，这可能会导致不期望的运动和异常扭矩。因此，蛇形机器人在实现自主运动方面存在知识空白。为了解决这个问题，本文提出了一种基于轻量级中枢模式发生器（CPG）模型的蛇形机器人平滑滑行步态转换控制方法。首先，基于梯度系统的收敛行为，设计了一种计算时间短的轻量级CPG模型，并与其他广泛采用的CPG模型进行了比较。然后，通过将身体重塑为更稳定的几何形状，对滑行步态进行了修改，并基于所提出的CPG模型进行了研究，包括运动速度、移动方向和身体形状的步态转换。与基于正弦曲线的方法相比，大量的仿真和原型实验最终表明，使用所提出的基于CPG的控制方法可以有效地实现平滑的滑行步态转换，而不会产生不期望的运动和异常扭矩。
