R&D Institute of Fluid and Power Engineering, Dalian University of Technology, Dalian 116024, China.
Sensors (Basel). 2021 Jan 12;21(2):494. doi: 10.3390/s21020494.
Untethered microrobots provide the prospect for performing minimally invasive surgery and targeted delivery of drugs in hard-to-reach areas of the human body. Recently, inspired by the way the prokaryotic flagella rotates to drive the body forward, numerous studies have been carried out to study the swimming properties of helical swimmers. In this study, the resistive force theory (RFT) was applied to analyze the influence of dimensional and kinematical parameters on the propulsion performance of conventional helical swimmers. The propulsion efficiency index was applied to quantitatively evaluate the swimming performance of helical swimmers. Quantitative analysis of the effect of different parameters on the propulsion performance was performed to optimize the design of structures. Then, RFT was modified to explore the tapered helical swimmers with the helix radius changing uniformly along the axis. Theoretical results show that the helical swimmer with a constant helix angle exhibits excellent propulsion performance. The evaluation index was found to increase with increased tapering, indicating that the tapered structures can produce more efficient motion. Additionally, the analysis method extended from RFT can be used to analyze the motion of special-shaped flagella in microorganisms.
无缆微型机器人为在人体难以到达的部位进行微创手术和靶向药物输送提供了前景。最近，受原核鞭毛旋转以推动身体前进的方式启发，人们进行了大量研究来研究螺旋游泳者的游泳特性。在这项研究中，应用阻力理论（RFT）来分析尺寸和运动学参数对常规螺旋游泳者推进性能的影响。推进效率指数用于定量评估螺旋游泳者的游泳性能。对不同参数对推进性能的影响进行了定量分析，以优化结构设计。然后，对 RFT 进行了修改，以探索沿轴均匀改变螺旋半径的锥形螺旋游泳者。理论结果表明，具有恒定螺旋角的螺旋游泳者表现出优异的推进性能。评估指标随着逐渐变细而增加，表明锥形结构可以产生更高效的运动。此外，从 RFT 扩展的分析方法可用于分析微生物中特殊形状鞭毛的运动。
