Faculty of Engineering, Kagawa University, 2217-20 Hayashi-cho, Takamatsu, Kagawa 761-0396, Japan.
Sensors (Basel). 2012 Dec 6;12(12):16732-58. doi: 10.3390/s121216732.
A variety of microrobots have commonly been used in the fields of biomedical engineering and underwater operations during the last few years. Thanks to their compact structure, low driving power, and simple control systems, microrobots can complete a variety of underwater tasks, even in limited spaces. To accomplish our objectives, we previously designed several bio-inspired underwater microrobots with compact structure, flexibility, and multi-functionality, using ionic polymer metal composite (IPMC) actuators. To implement high-position precision for IPMC legs, in the present research, we proposed an electromechanical model of an IPMC actuator and analysed the deformation and actuating force of an equivalent IPMC cantilever beam, which could be used to design biomimetic legs, fingers, or fins for an underwater microrobot. We then evaluated the tip displacement of an IPMC actuator experimentally. The experimental deflections fit the theoretical values very well when the driving frequency was larger than 1 Hz. To realise the necessary multi-functionality for adapting to complex underwater environments, we introduced a walking biomimetic microrobot with two kinds of motion attitudes: a lying state and a standing state. The microrobot uses eleven IPMC actuators to move and two shape memory alloy (SMA) actuators to change its motion attitude. In the lying state, the microrobot implements stick-insect-inspired walking/rotating motion, fish-like swimming motion, horizontal grasping motion, and floating motion. In the standing state, it implements inchworm-inspired crawling motion in two horizontal directions and grasping motion in the vertical direction. We constructed a prototype of this biomimetic microrobot and evaluated its walking, rotating, and floating speeds experimentally. The experimental results indicated that the robot could attain a maximum walking speed of 3.6 mm/s, a maximum rotational speed of 9°/s, and a maximum floating speed of 7.14 mm/s. Obstacle-avoidance and swimming experiments were also carried out to demonstrate its multi-functionality.
近年来，各种微型机器人在生物医学工程和水下作业领域得到了广泛应用。由于其结构紧凑、驱动功率低、控制系统简单，微型机器人可以完成各种水下任务，即使在有限的空间内也能完成。为了实现我们的目标，我们之前使用离子聚合物金属复合材料（IPMC）执行器设计了几种具有紧凑结构、灵活性和多功能性的仿生水下微型机器人。为了实现 IPMC 腿部的高精度位置，在本研究中，我们提出了一种 IPMC 执行器的机电模型，并分析了等效 IPMC 悬臂梁的变形和驱动力，该模型可用于设计仿生腿部、手指或微型机器人的鳍。然后，我们通过实验评估了 IPMC 执行器的尖端位移。当驱动频率大于 1Hz 时，实验挠度与理论值非常吻合。为了实现适应复杂水下环境所需的必要多功能性，我们引入了一种具有两种运动姿态的仿生步行微型机器人：躺卧状态和站立状态。微型机器人使用十一个 IPMC 执行器来移动，两个形状记忆合金（SMA）执行器来改变其运动姿态。在躺卧状态下，微型机器人实现了仿竹节虫的步行/旋转运动、仿鱼的游泳运动、水平抓取运动和漂浮运动。在站立状态下，它在两个水平方向上实现了仿尺蠖的爬行运动和垂直方向上的抓取运动。我们构建了这种仿生微型机器人的原型，并通过实验评估了其步行、旋转和漂浮速度。实验结果表明，机器人可以达到最大步行速度 3.6mm/s，最大旋转速度 9°/s 和最大漂浮速度 7.14mm/s。还进行了避障和游泳实验以证明其多功能性。
