| Micro/nano operation technology is widely used in material manufacturing,micro-electronic assembly,biomedical and other fields,and plays a crucial role in promoting the development of human science and technology.Optically induced dielectrophoresis(ODEP),as a new micro/nano manipulation technology,combined with optical technology and dielectrophoresis(DEP)technology,has the advantages of high efficiency,flexibility,reconfiguration,low power consumption and no damage.Furthermore,the manipulation of transportion,arrangement and separation of micro/nano particles have been widely concerned by many researchers.However,the traditional ODEP is mainly manual operation,depends on the operator’s proficiency,and the operation accuracy and efficiency are low.In view of this problem,this paper proposes the method of ODEP automatic manipulation,and the specific research content is described as follows:(1)In order to realize the accurate recognition and real-time tracking of micro/nano particles,a dynamic recognition method for particles is studied.Firstly,image processing,analysis and recognition methods are introduced into the ODEP system.Then,the images acquired by CCD are processed in turn by grayscale processing,image enhancement,morphology processing,binarization processing,edge detection,particle analysis and filtering,so as to complete the dynamic recognition of the target particles in the image.Therefore,the area,centroid coordinates,surrounding rectangle and other data information of the identified particle are obtained,and the tracking of the manipulated particle is further realized.So,the combination of dynamic identification method and ODEP system can obtain the relevant information of the manipulated particles in real time,which lays a foundation for the automatic control of micro/nano particles.(2)ODEP automatic manipulation system was built to automate a series of micro/nano particles.In this paper,the particle dynamic recognition method mentioned above is integrated into ODEP system,and combined with the automatic drawing and movement of optical patterns,it is integrated into ODEP automatic manipulation system by Lab VIEW software.According to the recognized size and centroid position of the manipulated particles,the optical pattern can be automatically drawn,and the operation of the manipulated particles can be captured and moved through the dynamic planning of the optical pattern.And using Saccharomyces cerevisiae cells as the controlled object,the system can not only realize the automatic transportation,arrangement and aggregation of micro/nano particles,but also can automatically separate the specific target particle in the mixed solution of two kinds of particles.(3)Aiming at the inaccuracy of traditional ODEP force calculation methods,a data-driven ODEP kinematics model and control method was proposed to achieve more accurate automatic control of micro/nano particles.In order to avoid the inaccurate problem of ODEP force caused by the assumptions required for the establishment of traditional ODEP force calculation expression,this paper adopts the method of data modeling to establish the kinematics model of ODEP,and designs the ODEP control system based on this,and further upgrades and improves the automatic control system of ODEP.Finally,the feasibility of the model and control system is verified in different application scenarios.To sum up,about the problems of low precision and efficiency of traditional ODEP manual operation,this paper developed an ODEP automatic operation system by using image recognition technology,Lab VIEW software development technology and data-driven modeling technology,and verified the feasibility of the system through practical operation experiments on micro/nano particles.The results display that this paper not only realizes the precise automatic control of micro/nano particles,but also plays a positive role in promoting the development of ODEP technology and promoting the application of ODEP technology. |
PDF Full Text Request