On The Key Arithmetic Units For Microfluidic Operation Systems

Fluid drive and logic control have become an important assurance for soft robotics.For example,bionic hand,rehabilitation equipment and bionic compound eyes all require pneumatic logic components to regulate multi-channel pressures,and realize the lightweight and integration.The fluid drive based on microfluidic technology can regulate the behavior of the fluid by the application of microvalves.As the scale and material are similar to the software robotics,it is considered as one of the major method for the control of soft robotics in the future.The research of microfluidic drive is just started,and the problems such as microvalve performance,basic logic gate construction,and implementation of complex logic function have not been in-depth research.Therefore,current microfluidic drivers are still difficult to implement rich logical functions such as digital circuits.In addition,the two-dimensional process of microfluidic devices is currently difficult to couple with the three-dimensional diversification of software robotics.How to realize the structural integration of drivers and soft robotics is also one of the key issues in the application of microfluidic drives.In this paper,the research on the key components of microfluidic arithmetic units is carried out for the control of soft robotics.The main work and results are as follows:(1)Aimed at the current digital microfluidic controller's requirements for digital arithmetic logic functions.A microfluidic logic device structure with addition and subtraction functions is proposed.A microfluidic addition and subtraction device with a calculation speed of about 2 Hz is realized,and the output pressure is converted into binary and decimal by the decoder structure.(2)3D printing process was used to solve the integration problemes in microfluidic controller.The results show that the 3D printed microfluidic decoder structure can reach a switching frequency of 2.5 Hz at 14 kPa.And the pressure regulating chip made of soft plastic material 3D printing method can realize the logic function of the third-order pressure adjustment.(3)By constructing a digital microfluidic minimum system to realize the integration of functional structures in the controller,the development of auxiliary components such as flip-flops,oscillators and digital-to-analog conversion is carried out.The experimental results of the minimum system show that the integrated device can achieve signal switching of 5 channels,and the response time is about 2.5s.(4)The need for zooming and address control functions for the lens array controller in software robotics.The digital microfluidic adder is the focusing structure,and the multi-channel decoding chip is the address control device.The digital control method of the pneumatic membrane lens array is studied,and the microfluidic driven hexagonal distributed lens array system is constructed.Experiments show that the pneumatic microlens array can realize the three step focal length adjustment and the positioning control of seven lenses,which lays a foundation for the coupling design of the future digital microfluidic chip and pneumatic bionic compound eye.