Legged robots have excellent terrestrial mobility for traversing diverse environments and thus have the potential to be deployed in a wide variety of scenarios. However, they are susceptible to falling and leg malfunction during locomotion. Although the use of a large number of legs can overcome these problems, it makes the body long and leads to many legs being constrained to contact with the ground to support the long body, which impedes maneuverability. To improve the locomotion maneuverability of such robots, the present study focuses on dynamic instability, which induces rapid and large movement changes, and uses a 12-legged robot with a flexible body axis. Our previous work found that the straight walk of the robot becomes unstable through Hopf bifurcation when the body axis flexibility is changed, which induces body undulations. Furthermore, we developed a simple controller based on the Hopf bifurcation and showed that the instability facilitates the turning of the robot. In this study, we newly found that the straight walk becomes unstable through pitchfork bifurcation when the body-axis flexibility is changed in a way different from that in our previous work. In addition, the pitchfork bifurcation induces a transition into a curved walk, whose curvature can be controlled by the body-axis flexibility. We developed a simple controller based on the pitchfork-bifurcation characteristics and demonstrated that the robot can perform a turning maneuver superior to that with the previous controller. This study provides a novel design principle for maneuverable locomotion of many-legged robots using intrinsic dynamic properties.
翻译:腿上的机器人在陆地上具有极好的流动性,可以穿行不同的环境,因此有可能在多种情况中部署。 但是, 在移动期间,它们很容易跌落和腿部故障。 虽然使用大量腿可以克服这些问题, 身体会长, 导致许多腿被迫与地面接触, 以支撑长的体形, 从而妨碍机动性。 为改善这种机器人的移动可操作性, 本研究侧重于动态不稳定, 导致快速和大规模移动变化, 并使用带有灵活体轴的12条腿型机器人。 我们先前的工作发现, 当身体轴灵活性被改变时, 机器人的直行会通过Hopf 双行变得不稳定, 从而导致身体的不适。 此外, 我们根据Hopf 双行图开发了一个简单的控制控制控制控制控制控制控制控制器, 从而有利于机器人的旋转。 在这项研究中, 我们发现直行会变得不稳定, 直行路路会变得不稳定, 与我们之前的工作不同。 此外, 直行的机械的机械性定型变变变变, 可以用一个简单的机械性变的曲线进行一个简单的旋转。