Research On Precise Ultrasonic Transducer And Driving Circuit

Micro manipulation is an important technology in the fields of instrument science, micro-nano technology and bioengineering. It has been used to nuclear transplantation, clone, inner cell information analysis, intracytoplasmic sperm injection, and assisted hatching. Combining the power ultrasonic driving technology with the traditional micro-manipulation technology, a novel technology of ultrasonic precise manipulation was presented in this paper. This technology can be used to penetration, injection, and suction for single cell.In this paper, the design theories of the ultrasonic transducer and the horn were presented. Four-Terminal Network Method was used to design a composite horn. Based on the Finite Element Simulation technology, the methods of model analysis and harmonic analysis were studied. The ANSYS Workbench platform was worked to simulate the design results of Four-Terminal Network Method. The parameters of precise ultrasonic transducer, such as amplitude, precise longitudinal vibration mode and resonance frequency, can all be calculated by Finite Element Analysis (FEA). The data was useful to the operation of experiments.Based on high-power operational amplifying and adaptive filtering techniques and coarse-to-fine follow-up strategy of frequency, a power ultrasonic signal source which has powerful driving ability and frequency tracing function was designed and completed. Therefore, the sinusoidal signal, whose amplitude can from 0 to 200V, frequency can be specified from 0 to 1MHz, and maximum power of 30W was outputted. The signal source was not only worked on the precise transducer, but also on other ultrasonic instruments such as medical scalpel and micro ejector.The amplitude and resonance frequency of the transducer were measured by a laser amplitude tester and a dynamic signal analyzer respectively. The experimental results were in close coincidence with the theoretical results and simulation. It indicated the reliability of design and the validity of the actual work. The performance test of signal source was completed, and the results were in line with expectations.By ultrasonic resonance driving, the numerical analyses and comparisons of precise transducer's amplitude, acceleration and puncture force proved the feasibility of ultrasonic precise manipulation in theory. A series of successful experiments on the fish eggs demonstrated the validity of ultrasonic precise manipulation in practice. The instantaneous penetration images captured by high speed photography (20000fps) implied the advantages of ultrasonic precise manipulator: reduced deformation, smaller harm, higher success rate.