Thesis ini mengandungi pendekatan dalam pemodelan bagi sebuah modul tujah dalam air yang telah dikembangkan oleh Underwater Robotic Research Group. Teknik dalam pemodelan ini memfokuskan kepada kotak-hitam sistem identifikasi dengan menggunakan perisian MATLAB/Simulink. Sistem tujahan terdiri daripada tiga blok system termasuk blok motor, blok bebaling, dan juga blok hidrodinamik. Pendekatan sistem identifikasi meringkaskan ketiga-tiga blok tersebut kepada satu blok model kotak-hitam. Masukan pada kotak-hitam tersebut adalah arus dan voltan, manakala keluarannya pula adalah daya tujah yang dihasilkan dan juga laju putaran dihasilkan. Untuk memudahkan teknik sistem identifikasi, sistem SISO (Masukan-Tunggal Keluaran-Tunggal) telah dikaji. Sistem SISO mengenalpasti masukan tunggal adalah kuasa yg dibekalkan kepada motor dan keluarannya pula adalah daya tujah yang dihasilkan. Bagi memastikan ketidaklurusan dalam sistem penujah berjaya dimodel, model Hammerstein-Wiener telah diadaptasikan. Sistem identifikasi memainkan peranan penting dalam mengaitkan semua faktor dalam penujah dengan menghasilkan pelampau dalam tindak balas sistem. Keberkaitan dalam factor-factor model telah dikenalpasti melalui matematik keberkaitan dalam analisa eksperimen. Dua model telah dihasilkan dalam simulasi, iaitu model masukan arus dan masukan kuasa. Fokus adalah lebih kepada masukan kuasa berikutan kemampuan model dalam menganggar daya kilas ketika penujah beroperasi di dalam air. Model simulasi disahkan dengan membandingkan keluaran simulasi dengan keluaran sebenar dalam daya tujah yg dihasilkan.
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This thesis contains modeling approach of specific underwater thruster module that has been developed by Underwater Robotic Research Group. The method in modeling mainly focused on black-box system identification method by using MATLAB/Simulink software. Thruster system composed of three block systems includes motor block parameters, propeller dynamics, and hydrodynamics block. System identification approach simplified the three block model into a black-box model. The input of the block model are current and voltage and the output of system are thrust and revolution speed produced. To simplify the system identification technique, SISO (Single-Input Single-Output) system has been investigated. SISO system define the input as power supplied and output define is thrust data. To cope with the thruster system nonlinearity, Hammerstein-Wiener block model has been investigated in term of model quality. System identification modeling approach play important role for the model, this is due to the overshoots and response produced by the model can be used to determine other parameters in thruster system. Correlation among the parameters is identified by using experimental analysis. The thesis also developed two simulation models which are current input based and power input based model. The main model on this thesis is the power model which has been developed with system identification technique by using the power correlation. The relationship among thruster parameters such as current, voltage, power, speed, thrust and torque has been related by mathematical expression produced from the experimental analysis. The power model developed is able to estimate thruster torque during underwater operation by the correlation of efficiency in the motor performance experiment. Finally, the developed model is validated by comparing simulation output and actual thrust output.
specific underwater thruster module; motor block parameters, propeller dynamics, and hydrodynamics block.; system identification technique, SISO (Single-Input Single-Output)
Modeling of an underwater thruster using matlab simulink_Khairul Anam Bin Mohd Huri_E3_2010_875003564-00003084254_NI