Lin Lin, Wu Hao, Xue Liwei, Shen Hao, Huang Haibo, Chen Liguo
Robotics and Microsystems Center, Soochow University, Soochow 215006, China.
Department of Mechanical Engineering, Xiamen Ocean Vocational College, Xiamen 361102, China.
Micromachines (Basel). 2021 Mar 15;12(3):309. doi: 10.3390/mi12030309.
An electrothermal microgripper is an important actuator in microelectromechanical and micro-operating systems, and its temperature field analysis is the core problem in research and design. Because of the small size of an electrothermal microgripper, its microscale heat transfer characteristics are different from those of the macrostate. At present, only a few studies on the heat transfer scale effect in electrothermal microgrippers have been conducted, and the heat transfer analysis method under the macrostate is often used directly. The temperature field analysed and simulated is different from the actual situation. In the present study, the heat transfer mechanism of an electrothermal microgripper in the microscale was analysed. The temperature field of a series of microscale heating devices was measured using microthermal imaging equipment, and the heat transfer parameters of the microscale were fitted. Results show that the natural convective heat transfer coefficient of air on the microscale can reach 60-300 times that on the macroscale, which is an important heat transfer mode affecting the temperature field distribution of the electrothermal microgripper. Combined with the finite element simulation software, the temperature field of the electrothermal microgripper could be accurately simulated using the experimental microscale heat transfer parameters measured. This study provides an important theoretical basis and data support for the optimal design of the temperature controller of the electrothermal microgripper.
电热微夹钳是微机电系统和微操作系统中的一种重要执行器，其温度场分析是研究与设计中的核心问题。由于电热微夹钳尺寸小，其微观尺度传热特性与宏观状态不同。目前，关于电热微夹钳传热尺度效应的研究较少，常直接采用宏观状态下的传热分析方法。所分析和模拟的温度场与实际情况存在差异。在本研究中，对电热微夹钳在微观尺度下的传热机理进行了分析。使用微热成像设备测量了一系列微观尺度加热装置的温度场，并拟合了微观尺度的传热参数。结果表明，微观尺度下空气的自然对流换热系数可达宏观尺度下的60 - 300倍，这是影响电热微夹钳温度场分布的一种重要传热方式。结合有限元模拟软件，利用实测的实验微观尺度传热参数能够准确模拟电热微夹钳的温度场。本研究为电热微夹钳温度控制器的优化设计提供了重要的理论依据和数据支持。
