Design And Implement Of Phased Arrays Ultrasonic Manipulation System Based On FPGA

It is known that ultrasonic standing wave can make quality lighter small particles trap in its sound pressure node, so it can by regular moving pressure nodes to achieve the suspending object manipulation. In the traditional research of one-dimensional acoustic manipulation system, the acoustic axis of the ultrasound beam and suspended particles in the direction of gravity parallel, and can manipulate the suspended object along the fixed acoustic axis by controlling the ultrasonic probe launch the phase or frequency of the ultrasonic.The paper presents a new design scheme of phased arrays ultrasonic manipulation system based on FPGA, in the three-dimensional space of the mid-air suspension control. We use four phased arrays to build the three-dimensional space environment of acoustic manipulation and generate an ultrasonic focal point in 3D space, and using the two probe opposite each other to produce ultrasonic standing wave, so standing wave nodes near the focus will have enough acoustic radiation force to balance the gravity of the small particle in the three-dimensional space, so as to achieve the purpose of the small particles are trapped in the mid-air. Then let the focus which generated by four phased arrays mobile following the movement of the nodes to ensure the small particles are stably and reliably manipulated. According to the new suspension, the ultrasonic standing wave manipulation system which designed, has two characteristics. One, the position and direction of ultrasonic standing wave which produced in three-dimensional space by the phased arrays are arbitrary; the other, ultrasonic focus follow the movement of the standing wave nodes to ensure the stability of node pressure. The ultrasonic frequency is 40 KHz and the manipulation environment is three-dimensional space in the air.First of all, the thesis analyzes the of domestic and foreign research status of ultrasonic standing wave suspension manipulation, recognizing the research and design of phased array ultrasonic manipulation system must have a very good understanding to the phased array ultrasonic emission focusing and phased array ultrasonic standing wave levitation principle. So, first of all, this paper studies the suspention mechanism of array ultrasonic standing wave, and analyzes the force situation of parallel the direction of the certain volume small sphere of polystyrene’s gravity.Secondly, this paper presents the overall design scheme of the phased array ultrasonic manipulation system, including the scheme of the USB3.0 turn to FPGA interface board, driver board, probe board and ACDC power. And according to the scheme using Cadence software to complete the design and implementation of hardware circuit, the most important is the design of the driver circuit on the drive plate. For subsequent validation the ultrasonic manipulation performance based on the new scheme build hardware platform.Then, the two main parts of the FPGA design of the system is designed and completed, including the design of the focus coordinate module and the launch delay module design and the simulation of the part of the design, and the use of ComSol5.0 software for three-dimensional sound field simulation and analysis.Finally, the driving unit circuit which designed is tested and analysed and the system hardware platform is builded and the small bubble particles which diameter is 1.5mm spreading into the three-dimensional mid-air 1.5mm are verified by experiments, and the results are analyzed.