Electronic Theses and Dissertation

Pengujian defleksi merupakan langkah penting untuk mengevaluasi elastisitas bahan dan memahami perilaku struktur saat terkena beban. Getaran kecil yang sering terjadi pada mesin dan struktur dapat menyebabkan defleksi yang memengaruhi kinerja dan keamanan. Berbagai metode non-kontak, seperti Digital Image Correlation (DIC), Speckle Pattern Interferometry (SPI), Optical Flow Analysis, Laser Doppler Vibrometry (LDV), dan Eulerian Video Magnification (EVM), telah digunakan untuk memantau defleksi. Penelitian ini menggunakan metode EVM karena kemampuannya memperbesar gerakan kecil dalam video, memungkinkan analisis mendalam terhadap perubahan bentuk dan karakteristik dinamis batang lentur akibat getaran motor. Penelitian ini bertujuan untuk merancang dan membangun sistem pengukuran defleksi menggunakan alat uji batang lentur serta menguji sistem tersebut. Berbagai metode pengukuran visual telah dikembangkan, salah satu metode pengukuran adalah Eulerian Video Magnification (EVM), yang mampu menguatkan pergerakan kecil dan perubahan pada video sehingga mempermudah pengamatan defleksi. Hasil penelitian menunjukkan bahwa pengukuran defleksi menggunakan EVM menghasilkan nilai defleksi puncak sebesar 4,6693 mm dan terendah -4,78208 mm, sedangkan akselerometer menunjukkan defleksi puncak 3,7646 mm dan terendah -3,7685 mm pada kecepatan 3600 RPM. Penelitian ini menunjukkan bahwa defleksi batang lentur meningkat seiring bertambahnya putaran motor, sesuai dengan penelitian sebelumnya. Kesimpulan ini mendukung validitas metode EVM sebagai alat yang efektif untuk mengamati variasi gerakan kecil pada bahan yang sulit diamati secara visual.

Deflection testing is a crucial step in evaluating material elasticity and understanding the behavior of structures under load. Minor vibrations that frequently occur in machines and structures can cause deflections that affect both performance and safety. Various non-contact methods, such as Digital Image Correlation (DIC), Speckle Pattern Interferometry (SPI), Optical Flow Analysis, Laser Doppler Vibrometry (LDV), and Eulerian Video Magnification (EVM), have been utilized to monitor deflection. This study employs the EVM method due to its ability to amplify subtle motions in videos, enabling in-depth analysis of shape changes and the dynamic characteristics of a bending beam caused by motor-induced vibrations. The objective of this research is to design and develop a deflection measurement system using a bending beam test apparatus and to evaluate its performance. Various visual measurement methods have been developed, among which Eulerian Video Magnification (EVM) is capable of enhancing small movements and changes in a video, thereby facilitating deflection observation. The results of the study indicate that deflection measurements using EVM produced a peak deflection value of 4.6693 mm and a minimum of -4.78208 mm, while measurements using an accelerometer showed a peak deflection of 3.7646 mm and a minimum of -3.7685 mm at a motor speed of 3600 RPM. The findings also demonstrate that the deflection of the bending beam increases with higher motor speed, consistent with previous research. These conclusions support the validity of the EVM method as an effective tool for observing small motion variations in materials that are difficult to detect visually