Hasil Pencarian  ::  Simpan CSV :: Kembali

"Pada tesis ini, dilaporkan hasil pengujian deteksi getaran di dalam air dengan menggunakan Fiber Bragg Grating (FBG) Accelerometer 3 sumbu yang terdiri dari 3 buah FBG. Pompa air digunakan sebagai sumber getaran di dalam air dengan variasi posisi dari 0 hingga 10 cm. Hasil pengujian ditampilkan dalam bentuk perubahan panjang gelombang Bragg yang direfleksikan dan frekuensi. Pada tahap pertama, pengujian dilakukan di dalam box kontainer dengan ukuran 78 cm x 56 cm x 46 cm dengan ketinggian air sebesar 17 cm. Dari hasil pengujian pertama ditunjukkan bahwa seiring pertambahan jarak, saat pompa air berada pada FBG X, Y, atau Z maka panjang gelombang Bragg FBG X, Y, atau Z mengalami perubahan paling signifikan dengan nilai R-squared di atas 98%. Pada tahap kedua, pengujian dilakukan di dalam kolam air dengan ukuran 264 cm x 163 cm x 66 cm dengan ketinggian air sebesar 24 cm. Dari hasil pengujian kedua ditunjukkan bahwa seiring pertambahan jarak, saat pompa air berada pada FBG X, Y, atau Z, panjang gelombang Bragg FBG X, Y, atau Z mengalami perubahan paling signifikan dan menurun secara linier dengan gradien dan R-sqaured sebesar 0,0114 nm/cm dan 99,77%; 0,0124 nm/cm dan 99,71%; 0,0071 nm/cm dan 99,54%. Selanjutnya seiring pertambahan jarak, perubahan frekuensi menurun secara linier dengan gradien dan R-squared berturut-turut sebesar 1,4751 Hz/cm dan 99,53%; 1,6286 Hz/cm dan 99,82%; 1,7714 Hz/cm dan 99,84% untuk FBG X, Y, dan Z. Ditunjukkan pula bahwa eiring dengan pertambahan jarak, nilai strain dan akselerasi menurun. Hak ini menyebabkan nilai frekuensi menurun oleh karena hubungan langsung dengan strain dan akselerasi dan membutuhkan waktu yang lebih lama agar gelombang getaran mencapai FBG Accelerometer. Berdasarkan hasil perubahan frekuensi yang diterima oleh FBG X pada kondisi di udara dan di dalam air, nilai frekuensi dan amplitudo mengalami penurunan yang lebih signifikan di dalam air dibandingkan pada udara oleh karena redaman getaran oleh air, menambahkan momen inertia, dan menambahkan noise pada FBG. Dari hasil perhitungan transmisi data, terdapat delay sebesar 0,044 ms dengan kecepatan internet 7,5 Mbps dan nilai delay ini masuk dalam kategori sangat baik.

---

In this thesis, the results of vibration detection underwater using Fiber Bragg Grating (FBG) Accelerometer 3-axis consisted of 3 FBGs are reported. Water pump is employed as vibration source with varied positions from 0 to 10 cm. The testing results are presented in the form of Bragg wavelength shift and frequency. On first stage, testing was conducted inside the container box with the dimensions of 78 cm x 56 cm x 46 cm with the water height of 17 cm. From the first testing results, it is shown that with increasing distance, when water pump is placed on FBG X, Y, and Z, Bragg wavelength of FBG X, Y, and Z has the most significant change and R-squared value above 98%. On second stage, testing was conducted inside the small pool with the dimensions of 264 cm x 163 cm x 66 cm with the water height of 24 cm. From the second testing results, it is shown that with increasing distance, when water pump is on FBG X, Y, and Z, Bragg wavelength FBG X, Y, and Z has the most significant change and decreases linearly with successive gradients and R-squared values of 0,0114 nm/cm and 99,77%; 0,0124 nm/cm and 99,71%; 0,0071 nm/cm and 99,54%. It is also shown that with increasing distance, the frequency decreases linearly with successive gradients and R-squared values of 1.4751 Hz/cm and 99.53%; 1.6286 Hz/cm and 99,82%; 1,7714 Hz/cm and 99,84% for FBG X, Y, and Z. It also shown that as distance increased, the strain and acceleration value decreased. This caused frequency value to decrease because frequency is linearly connected to strain and acceleration and it takes longer for vibration wave to reach FBG Accelerometer. Based on frequency change received by FBG X on air and inside the water, the frequency and amplitude decreased more inside the water than on air because of viscosity damping of water, increase inertia moment, and increase noice on FBG. From data transmission calculations, the delay value is 0,044 ms with the internet speed of 7,5 Mbps and this value classified as very good."

"Fiber Bragg grating (FBG) merupakan divais optoelektronika yang bekerja dengan cara menyaring panjang gelombang yang melaluinya. Nilai panjang gelombang tersebut ditentukan oleh indeks bias efektif struktur FBG. Sebagai sensor yang sensitif terhadap tekanan dan temperatur, FBG memiliki potensi pengaplikasian yang luas. Pada penelitian ini dilakukan deteksi tekanan hidrostatik rendah sebagai dasar pengembangan FBG single-mode berstruktur uniform sebagai sensor tekanan dalam air serta pengamatan pengaruh temperatur optical interrogator terhadap hasil pengukuran yang diperoleh. Pada tahap awal, dilakukan karakterisasi FBG untuk berbagai tekanan yang diwakili oleh berbagai beban dalam rentang 0 gram hingga 500 gram dengan kenaikan 50 gram. Berdasarkan hasil tersebut, selanjutnya dilakukan eksperimen pengukuran tekanan hidrostatik sedang dari arah 180° untuk melihat pengaruh arah tekanan pada FBG. Eksperimen tersebut dilakukan dengan rentang 0 liter hingga 20 liter dengan kenaikan volume air 2,5 liter dan menghasilkan hubungan linier dengan gradien negatif saat diberikan tekanan dari arah bawah FBG. Selanjutnya dilakukan juga  eksperimen pengukuran tekanan hidrostatik rendah arah vertikal tegak lurus FBG dengan rentang 0 ml hingga 10 ml dengan kenaikan volume air 0,25 ml. Hasil penelitian menunjukkan bahwa terdapat hubungan yang linier antara tekanan hidrostatik rendah dengan panjang gelombang Bragg dengan sensitivitas sebesar 0,0004142 nm/(Pa°C).

---

Fiber Bragg grating (FBG) is an optoelectronic device that operates by filtering the wavelength passing through it. The wavelength value is determined by the effective refractive index of the FBG structure. As a sensor that is sensitive to both pressure and temperature, FBG has wide-ranging potential applications. In this study, the detection of low hydrostatic pressure was performed as the basis for developing a uniform structured single-mode FBG as an underwater pressure sensor. Initially, FBG characterization was conducted for various pressures represented by different loads ranging from 0 grams to 500 grams with a 50-gram increment. Based on these results, subsequent experiments were carried out to measure moderate hydrostatic pressure from the 180° direction to observe the effect of pressure direction on FBG. The experiment was performed with a range of 0 liters to 20 liters, with a 2.5-liter increment in water volume, and yielded a linear relationship with a negative gradient when pressure was applied from below the FBG. Furthermore, experiments were conducted to measure low vertical hydrostatic pressure with a range of 0 ml to 10 ml, using a 0.25 ml increment in water volume. The research findings indicate a linear relationship between low hydrostatic pressure and Bragg wavelength, with a sensitivity of 0,0004142 nm/(Pa°C)."

"[Pada umumnya sensor Fiber Bragg Grating (FBG) bekerja berdasarkan pengamatan karakteristik respon spektral FBG terhadap besaran yang ingin dideteksi. Pada tesis ini dipelajari kemungkinan pemanfaatan respon intensitas FBG untuk mengamati besaran yang ingin dideteksi, khususnya regangan statis dan dinamis. Hasil pengujian menunjukkan bahwa intensitas transmisi dan refleksi FBG berbanding lurus dengan regangan statis dan dinamis. Berdasarkan karakteristik FBG tersebut, dilakukan rancang bangun sensor getaran FBG untuk mendeteksi getaran pada frekuensi rendah. Sensor ini dibuat dengan cara menempelkan sebuah FBG pada kantilever berbahan perunggu dengan dimensi 85x3x0,5 mm. Hasil pengukuran pada rentang temperatur 25 ? 450C menunjukkan bahwa sensor ini dapat mendeteksi getarandalam rentang frekuensi 7?10 Hz. Rentang frekuensi ini termasuk dalam rentang frekuensi aktivitas penggalian, sehingga dapat diterapkan pada sistem deteksi tindakan vandalisme pada jalur pipa minyak.;In general, Fiber Bragg Grating (FBG) sensor works based on the observation of spectral response characteristic to detect the desired parameter. In this thesis, we studied the possibility of using the FBG intensity response characteristic to detect the desired parameter,especially in static and dynamic strain. Experiment result show that the transmitted and reflected intensity have linier relationships with static and dynamic strain. Based on these characteristics, we developed the FBG sensor to detect low frequency vibration. This sensor is designed by attaching the FBG on the bronze cantilever with dimensions of 85x3x0.5 mm. Measurement results show that the sensor is able to detect vibrations in the frequency range of 7-10 Hz at a temperature range of 25-450C. The measured frequency range is still within thefrequency range of digging activity, therefore this vibration sensor can be applied on oil pipelines vandalisation detection system.;In general, Fiber Bragg Grating (FBG) sensor works based on the observation ofspectral response characteristic to detect the desired parameter. In this thesis, we studied thepossibility of using the FBG intensity response characteristic to detect the desired parameter,especially in static and dynamic strain. Experiment result show that the transmitted andreflected intensity have linier relationships with static and dynamic strain. Based on thesecharacteristics, we developed the FBG sensor to detect low frequency vibration. This sensor isdesigned by attaching the FBG on the bronze cantilever with dimensions of 85x3x0.5 mm.Measurement results show that the sensor is able to detect vibrations in the frequency range of7-10 Hz at a temperature range of 25-450C. The measured frequency range is still within thefrequency range of digging activity, therefore this vibration sensor can be applied on oilpipelines vandalisation detection system., In general, Fiber Bragg Grating (FBG) sensor works based on the observation ofspectral response characteristic to detect the desired parameter. In this thesis, we studied thepossibility of using the FBG intensity response characteristic to detect the desired parameter,especially in static and dynamic strain. Experiment result show that the transmitted andreflected intensity have linier relationships with static and dynamic strain. Based on thesecharacteristics, we developed the FBG sensor to detect low frequency vibration. This sensor isdesigned by attaching the FBG on the bronze cantilever with dimensions of 85x3x0.5 mm.Measurement results show that the sensor is able to detect vibrations in the frequency range of7-10 Hz at a temperature range of 25-450C. The measured frequency range is still within thefrequency range of digging activity, therefore this vibration sensor can be applied on oilpipelines vandalisation detection system.]"

"Penanganan lucutan korona dan efeknya pada saluran transmisi saat ini masih bergantung pada hasil inspeksi lapangan yang memerlukan waktu serta tenaga banyak sehingga dapat dikembangkan sistem untuk pemantauan keadaan jarak jauh. Lucutan korona menyebabkan perubahan temperatur pada permukaan material dikarenakan adanya perubahan koefisien transfer panas. Apabila kondisi uji lucutan korona memenuhi kondisi agar pemanasan joule dan pemanasan matahari dapat diabaikan maka faktor penentunya adalah radiasi panas pada material uji. Radiasi panas tersebut menyebabkan turunnya temperatur akibat timbulnya angin ionik. Serat kisi Bragg merupakan salah satu sensor optik yang banyak digunakan untuk mendeteksi perubahan temperatur. Oleh karena itu, dalam penelitian ini dirancang model simulasi sensor temperatur menggunakan serat kisi Bragg. Simulasi dilakukan menggunakan perangkat lunak OptiSystem. Hasil simulasi menghasilkan rangkaian dengan hubungan antara temperatur dan panjang gelombang terbaca linear dengan spektrum memiliki pusat gelombang yang jelas, side lobe diatas -20 dB serta bandwidth mencakup rentang temperatur yang ingin diuji berdasarkan literatur.

---

Nowadays, corona discharge inspection is done by visual inpection which cost much time and energy therefore it is necessary to develop remote sensing system to monitor the phenomenon. But before that, proof of concept for monitoring corona discharge must be proven. Corona discharge causes change in temperature on a material surface because of the changing in conductor heat coefficient. If the experiment fulfil specific condition, effect of joule heating and solar heat can be ignored and radiated heat is the only factor that should be considered in the change of heat transfer coefficient. Fiber Bragg grating is one of optical sensor used to sense change of temperature. In this study, a temperature sensor simulation model was designed using fiber Bragg grating. Simulation was done on OptiSystem software. Simulation result will be used to predict the wavelength read on optical spectrum analyzer based on past experiment data. The simulation resulted on differentiable center wavelength, side lobe more than -20 dB, and bandwidth that covered the desired temperature range."