VFO feedback control using positively-invariant funnels for mobile robots travelling in polygonal worlds with bounded curvature of motion
VFO feedback control using positively-invariant funnels for mobile robots travelling in polygonal worlds with bounded curvature of motion
复制标题
使用正不变漏斗的 VFO 反馈控制用于在具有有限运动曲率的多边形世界中行驶的移动机器人
DOI：
10.1109/aim.2017.8014006
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
M. Michałek
中科院分区：
文献类型：
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作者：
Tomasz Gawron;M. Michałek
移动的机器人的反馈控制在机器人系统的实际应用中至关重要，它保证了环境中障碍物产生的状态约束和机器人机械结构施加的输入约束的保持。运动执行的安全性通常是由一种策略来保证的，该策略是通过一系列漏斗来驱动机器人，这些漏斗表示用于所利用的反馈控制律的机器人配置空间的安全的、正不变的子集。在本文中，VFO（矢量场定向）控制法的杠杆开发这样的反馈控制策略的有界曲率的运动的单关节机器人。所提出的漏斗的定义自然产生于曲率约束下的VFO控制律的分析。环境中的障碍物通过使用额外的人工曲率约束收缩漏斗来处理。本文提出一种计算漏斗的精确解析方法。为了使漏斗具有正不变性并保证运动安全，对原有的VFO控制律进行了修正。与文献中的许多方法相比，所提出的反馈控制策略确保了在漏斗之间的过渡期间控制信号的至少C1连续性。我们的方法的有效性已被验证的模拟，在此期间，机器人被驱动通过一系列的漏斗计划在混乱的环境中使用RRT* 算法。
Feedback control of mobile robots guaranteeing preservation of state constraints resulting from obstacles in the environment and input constraints imposed by robot mechanical construction is essential in practical applications of robotic systems. The safety of motion execution is often ensured by a strategy of driving the robot through a sequence of funnels representing safe, positively invariant subsets of robot configuration space for utilized feedback control laws. In this paper, the VFO (Vector Field Orientation) control law is leveraged to develop such a feedback control strategy for a unicycle robot with bounded curvature of motion. The proposed definition of funnels arises naturally from analysis of the VFO control law under curvature constraints. Obstacles in the environment are handled by shrinking the funnels using additional artificial curvature constraints. An exact analytic method for computation of funnels is presented. To make the funnels positively-invariant and guarantee motion safety, the original VFO control law has been modified. In contrast to numerous methods available in the literature, proposed feedback control strategy ensures at least C1 continuity of the control signals during transitions between funnels. Effectiveness of our approach has been verified by simulations, during which the robot was driven through a sequence of funnels planned in the cluttered environment using the RRT* algorithm.