| As a new developed rapid manufacturing method, uniform droplets spraying rapid prototyping is based upon a layered manufacturing paradigm: alternative charged droplets is deposited onto a movable substrate by controlling electric field to fabricate 3-D complex shaped prototyping in a single process. The technology succeeds in forming high melting point parts with good performance. In addition, it has the advantages in low cost and non-aftertreatment. Therefore it has a potential application in aviation and micro weapon equipment. In this thesis, the whole configuration and the main parameters of the micro forming system are presented in details, and uniform droplets generator device has been developed. All the research establishes a base for studying the process of droplets generation, flight and deposition.In the process of droplet spraying, some key parameters, such as temperature, gas pressure, actuator frequency, affect directly the quality of droplets. A measurement and control system for spraying device has been developed based on LabVIEW. This system communicates with traditional instrument through RS-232 serial port, measures process variable using PCL-818L, and by improving actual PID controller, realizes temperature and gas pressure precise control in virtue of PID control toolkit in LabVIEW.Disturbance source, which is one of the key components in the droplets generator, is provided by piezoelectric oscillator. Test indicates piezoelectric oscillator is satisfied with the requirement of the process.The mathematic model of droplets spraying process is established. Through the model analysis and test validation, the influences of certain key factors, such as temperature, oscillation frequency, gas pressure, infiltration pressure, orifice diameter and etc., on the process were investigated systematically. The effect law among technique parameters is disclosed, and it will guide the further study on UDS rapid prototyping.
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