Research On Regulation Technology Of Magnetically Driven Swimming Microrobot Swarms

The size of the swimming microrobot is between several micrometers and hundreds of micrometers,which can convert magnetic energy,light energy,sound energy or other forms of energy into mechanical motion in a liquid environment.Due to its extremely high control accuracy and controllability in restricted environments,microrobots have broad application prospects in biomedicine,environmental remediation and other fields,such as targeted drug delivery,minimally invasive surgery,cell manipulation,heavy metals detection,pollutant removal,etc.Limited by the size,the individual capabilities of microrobots are limited and the efficiency is low,and it is difficult to meet the needs of practical applications.Inspired by the phenomenon of biological collective behaviors in nature,the microrobot swarms has strong task execution ability and adaptability to complex terrain,and how to realize the effective control of the swarm is a problem that needs to be solved urgently.In this paper,the magnetic swimming microrobot is taken as the research object,starting from the individual dynamic characteristics of the microrobot,the collective model of microrobots in the coupling field(the coupling of magnetic field and fluid field)is established.Basing on the driving system of magnetic microrobots,and the regulation of microrobot swarms dominated by magnetic dipole force,hydrodynamic force and switchable force is realized,respectively.Besides,the multimode transformation,solid-like characteristic,and liquid-like characteristic of the microrobot swarms are also verified by experiment.This paper lays the foundation for the application of magnetically driven swimming microrobot swarms in the field of biomedicine.The collective model of the magnetically driven swimming microrobots is carried out.Based on the active Brownian particle swarm dynamics model,the dynamics model of microrobot swarms is established by analyzing the individual dynamics of microrobots in the coupling field,revealing the emergence of collective behaviors of microrobots and regulatory mechanisms.On this basis,in order to realize the individual motion control of the microrobots and the effective control of the swarm,a full-degree-of-freedom magnetic vector motion control method is proposed,and a broadband magnetic driven swarm control system with a drive frequency of 1000 Hz is constructed.The controllable regulation of microrobot swarms dominated by magnetic dipole force is studied.Aiming at the current problem of insufficient stability of the microrobot swarms,a method for magnetic interaction to induce the emergence of swarm of the sea urchin-like microrobots is proposed.Using the biological template method,the sea urchin-like magnetic microrobots with the pollen sporopollen shell as the main body is constructed.The experimental results show that the swarm of sea urchin-like microrobots based on the magnetic dipole force has excellent stability,and can complete experimental tasks such as intracellular targeted drug delivery and contact and non-contact micromanipulation.The controllable regulation of microrobot swarms dominated by hydrodynamic force is studied.Aiming at the problem of single mode of homogeneous microrobot swarms,a method for fluid interaction to induce the swarm of peanut-like microrobots is proposed.The peanut-like magnetic microrobots are prepared by the water bath synthesis method.In the homogeneous microrobot swarms system,the excitation of multi-modal swarm behavior and the controllable conversion between swarm modes are realized.The experimental results show that the swarm of peanut-like microrobots based on the fluid force has excellent deformability,can realize controllable navigation movement in complex environment,and complete the task of cooperative operation,and transport objects that are40000 times more than its own volume.The controllable regulation of microrobots dominated by switchable forces is studied.Based on the swarm dynamics model of microrobots in the coupling field,a control method of swarm emergence of spherical microrobots dominated by switchable forces is proposed.The ultrasonic dispersion method is used to prepare spherical magnetic microrobots in batches.It not only realizes the multi-modal excitation of the microrobot swarms,but also realizes the controllable conversion between the liquid-like and solidlike characteristics of the swarm.The experimental results show that the magnetic dipole force/hydrodynamic force can respectively induce the swarm of spherical microrobots,which has excellent stability and strong deformability,can realize all-terrain navigation movement and climb over steps and gaps 40 times larger than its own size and has a variety of swarm operation modes.In summary,this paper aims at the problem of microrobot's individual task execution ability and weak adaptability to the surface environment.The regulation of microrobot swarms dominated by magnetic dipole force,hydrodynamic force and switchable force is realized,respectively.The method of batch preparation and controllable movement of individual microrobots is proposed.The controllable emergence,multi-mode transformation and collaborative operation of microrobot swarms are verified by experiment,and solves the problems of low efficiency and poor flexibility of microrobots that cannot meet actual needs.Effectively improve the adaptability and task execution ability of the microrobot swarms in complex terrain.The research will promote the application of micro-robots in the fields of biomedicine,environmental processing,etc.,and has important research value and application prospects.