İki Eksenli Esnek bir Manipülatörün ANSYS APDL ile Modellenmesi ve Titreşim Kontrolü

Bu çalışmada, iki eksenli esnek bir manipülatörün hareket sonrası artık titreşimlerinin kontrolü incelenmiştir. Manipülatör ANSYS'de APDL (Ansys Parametrik Tasarım Dili) kullanılarak modellenmiştir. Hareket sonrası titreşim sinyalleri, sonlu elemanlar teorisine dayalı olarak ANSYS'de gerçekleştirilen dinamik analiz ile simüle edilir. Önceki çalışmada elde edilen deney sonuçları da sunulmuş ve benzetim sonuçları ile karşılaştırılmıştır. Tahrik motorları için trapez hız profilleri kullanılmıştır. Trapez hız profilinin ivme, sabit hız ve yavaşlama süreleri, durdurma pozisyonundaki manipülatör yapısının en düşük doğal frekansı dikkate alınarak seçilir. Çeşitli başlangıç ve durma pozisyonları değerlendirilmiştir. Hareket bittikten sonra meydana gelen artık titreşim sinyallerinin karelerinin ortalamasının karekök (RMS) değerleri hesaplanır. Artık titreşimin yavaşlama süresine duyarlı olduğu gözlemlenmiştir. RMS değerleri, yavaşlama süresinin tersi ilk doğal frekansa eşitse, en düşük değer elde edilmektedir. Yavaşlama zamanının tersi ilk doğal frekansın yarısına eşitse, en yüksek değer elde edilir. Benzetim ve deney sonuçlarının birbirleriyle uyumlu çıktığı görülmektedir.

Modeling and Vibration Control of a Two-Link Flexible Manipulator with ANSYS APDL

In this study, the control of post-motion residual vibrations of a two-link flexible manipulator is investigated. The manipulator is modeled in ANSYS by using APDL (Ansys Parametric Design Language). The post-motion vibration signals are simulated by transient analysis which is performed in ANSYS based on the finite element theory. Experimental results are also presented and compared with simulation results. Trapezoidal velocity profiles are used for the motors. The acceleration, constant velocity and deceleration time intervals of the trapezoidal velocity profile are determined by considering the lowest natural frequency of the manipulator structure at the stopping position. Various starting and stopping positions are considered. The root mean square (RMS) acceleration values of the vibration signals after stopping are calculated. It is observed that the residual vibration is sensitive to the deceleration time.  The RMS values are lowest if the inverse of the deceleration time is equal to the first natural frequency.  It is highest if the inverse of the deceleration time is equal to the half of the first natural frequency. It is observed that simulation and experimental results are in good agreement.

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