| Summary: | 碩士 === 國立交通大學 === 影像與生醫光電研究所 === 104 === This study proposes design, dynamic modeling and drive system of a two degree-of-freedom (DOF) rotational optical image stabilizer (OIS) in the camera embedded in the mobile devices. This OIS differs from the previous designs since it stabilizes the angular position between lens holder and image sensor by a two-DOF rotational mechanism that is actuated by voice coil motors (VCM). It can provide a solution for a fuzzy image due to the hand-shaking. Such category of technology will enable cameras-phones images reaching more clear effect. The work can be divided into three main parts: designs of mechanism, establishments of the dynamic model and equation of motions (EOM) of a rotational structure, and realizations of a proportional–integral–derivative (PID) controller with high-precision. The first part focuses on the rotational movements (in x/y axes) by adopting optimized yokes and magnets to provide optimal magnetic fields for actuation. In the second part, the dynamic of the rotational OIS system has been analyzed and the EOM has been derived. Based on the Lagrange’s method, the motions of the OIS have been modeled through considering kinetic energy and electromagnetic torques. In the last part, the theory of PID control is applied, and the associated simulations are conducted. Based on the simulation results, the PID controller is forged with the assistances from MATLAB pre-simulation and tested by a microprocessor module. The controller would be built up to match the design which contains the drive system for anti-shake mechanism. After a series of experiments and verifications, the prototype of the novel OIS is finally accomplished with satisfactory performance of vibration reduction. The designed OIS module can reach a control tilting range of ±1 degree in the required 0.5 second. As the maximum output current is 40 mA.
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