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Electrospun polymer nanofibers are more and more widely applied in many fields, such as nanochannel in biological detection, micro-nano optical fiber and waveguide, electronic components and sensors, etc. The requirement of the mentioned applications guides electrospun deposition to orderly structure, even to controllable pattern. This thesis mainly focuses on the construction of motion platform of Electrohydrodynamic Direct-writing (EDW) System, the depositing regularity of micro/nano structure, and the pattern depostion and its error analysis of direct written pattern structure.For direct-writing pattern based on electrospinning, it is necessary to construct motion platform and test its performance. The drive module of motion platform includes linear motor (XY two-dimensional motion plane) and servo motor (Z axis); the control module includes industrial control computer, control cards and drives. In addition, proximity switch is integrated in the control circuit to obtain limit and safety function. Via the upper industrial control computer, platform motor achieves satisfactory performance by setting parameters and using PIV&F control algorithm. The vibration of platform, in power-on condition, is1.7292μm, linear shape error23.331μm, surface shape error54.02μm, XY motion plane positioning error15.0μm, repetitive positioning error5.0μm.Based on the motion platform, it is possible to obtain pattern deposition and analyze the parameters of motion platform and EDW processing, which inluence deposition morphology. The influence of platform motion on jet is "shaping" under low concentrations (8wt%) and "straightening" under high concentrations (16wt%). In the condition that motion direction changes suddenly, motors vibrate, which distorts deposition. To avoid motors vibration, it is necessary to set standstill at the corner. The longer the duration of standstill, the more excessive deposition. The excessive deposition shows liquid gathering under low concentration (8wt%) and solid assembling under high concentration (16wt%). Platform motion parameter, especially the velocity of collector, must be optimized with coupling appropriate duration of standstill, PEO solution concentration, distance between nozzle and collector, distance between deposited lines, etc. Combined with the motion platform and the deposition regularity,2D patterns can be direct-written. The most outstanding advantage of the motion platform integrated with grating sensor is tracking motors trajectory, which make error analysis possible by comparing motors trajectory with deposited pattern.Experimental results illustrate that EDW System Motion Platform provieds an effective method for electrospun pattern deposition and its error analysis.
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