Interpretasi Objek Dasar Laut Berdasarkan Nilai Hambur Balik Menggunakan Instrumen Side Scan Sonar (Studi Kasus Pipa Pertamina di Balongan)

Side scan sonar merupakan instrumen single beam yang mampu menunjukkan gambar dua dimensional permukaan dasar laut dengan kondisi kontur, topografi dan target secara bersamaan. Teknologi ini merupakan penginderaan jauh akustik untuk pemetaan sedimen dan struktur dasar laut. Side scan sonar merekam energi gelombang akustik yang dipancarkan oleh hambur balik dasar laut sehingga mampu membedakan besar kecil partikel penyusun permukaan dasar laut. Pengaruh dari intensitas hambur balik tergantung pada tipe, magnitudo dan orientasi dari kekasaran dasar perairan yang dapat mendeskripsikan dasar laut. Penelitian ini bertujuan untuk memvisualisasikan dan menginterpretasikan hasil pengolahan data dari side scan sonar pada pendeteksian target yang berupa pipa diperairan Balongan, estimasi dimensi dan posisi pipa, menentukan nilai amplitudo hambur balik pipa dan menganalisis respon hambur balik dari pipa. Pemrosesan data side scan sonar dilakukan menggunakan koreksi geometrik untuk menetapkan posisi yang sebenarnya pada pixel citra yang terdiri dari bottom tracking, slant range correction, layback correction dan koreksi radiometrik dilakukan untuk intensitas hambur balik pada digital number yang ditetapkan pada setiap pixel meliputi Beam Angle Correction (BAC), Automatic Gain Control (AGC), Time Varying Gain (TVG) dan Empirical Gain Normalization (EGN). Lokasi penelitian berada di sekitar Pelabuhan Balongan menggunakan instrumen side scan sonar C-MAX CM2 dengan frekuensi 325 kHz. Pengolahan data menggunakan perangkat lunak SonarWiz 5 dengan melakukan beberapa koreksi yang kemudian data hasil olahan di ekstrak menggunakan perangkat lunak XtfTosegy selanjutnya di ekstrak dengan perangkat lunak Seisee untuk menghasilkan data dengan format *.txt dan hasilnya diolah dengan perangkat lunak Matlab untuk menampilkan grafik yang dapat menunjukan nilai amplitudo dari target yang terdeteksi. Dimensi objek hasil dari pengukuran target yaitu Target pipa 1 memiliki lebar (diameter) 0,9 meter, tinggi 0,64 meter, nilai amplitudo sebesar 23.420 – 32.000 mV dan memiliki nilai hambur balik sebesar -2,71 dB. Target pipa 2 lebar(diameter) 0,9 meter, tinggi 0,35 meter dengan nilai amplitudo 20.104 – 31.100 mV dan memiliki nilai hambur balik sebesar -3,06 dB. Sedangkan target substrat dasar perairan memiliki amplitudo hambur balik 4.480 – 17.660 mV dan nilai hambur balik -11,91 dB. Hasil analisa dapat diartikan bahwa target pipa 1 dan pipa 2 memiliki kekerasan yang lebih dibandingkan dengan dasar laut. Dilihat dari nilai hambur balik dan bentuk secara 2D dipastikan target pipa 1 dan pipa 2 terbuat dari besi dengan nilai impedansi akustik 478,85 x 105 kg/m2s dan koefisien refleksi 0,928.

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Seabed Detection Using Application Of Image Side Scan Sonar Instrument (Acoustic Signal)

Journal of Geoscience Engineering Environment and Technology ◽

10.24273/jgeet.2017.2.3.560 ◽

2017 ◽

Vol 2 (3) ◽

pp. 230

Author(s):

Muhammad Zainuddin Lubis ◽

Husnul Kausarian ◽

Wenang Anurogo

Keyword(s):

Acoustic Signal ◽

Automatic Gain Control ◽

Gain Control ◽

Special Equipment ◽

Radiometric Correction ◽

Side Scan Sonar ◽

Single Beam ◽

Angle Correction ◽

Range Correction ◽

Signal Method

The importance of knowing the method for seabed detection using side-scan sonar images with sonar instrument is a much-needed requirement right now. This kind of threat also requires frequent sonar surveys in such areas. These survey operations need specific procedures and special equipment to ensure survey correctness. In this paper describes the method of observation and retrieval of marine imagery data using an acoustic signal method, to determine a target based on the sea. Side scan sonar is an instrument consisting of single beam transducer on both sides. Side scan sonar (SSS) is a sonar development that is able to show in two-dimensional images of the seabed surface with seawater conditions and target targets simultaneously. The side scan sonar data processing is performed through geometric correction to establish the actual position of the image pixel, which consists of bottom tracking, slant-range correction, layback correction and radiometric correction performed for the backscatter intensity of the digital number assigned to each pixel including the Beam Angle Correction (BAC), Automatic Gain Control (AGC), Time Varied Gain (TVG), and Empirical Gain Normalization (EGN).

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Research on Measurement Method of Ultrasonic Transit Time based on Automatic Gain Control

2020 39th Chinese Control Conference (CCC) ◽

10.23919/ccc50068.2020.9188416 ◽

2020 ◽

Author(s):

Qinyong Ma ◽

Yuanzheng Zhang

Keyword(s):

Transit Time ◽

Measurement Method ◽

Automatic Gain Control ◽

Gain Control

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Measuring Current in a Power Converter Using Fuzzy Automatic Gain Control

Applied Sciences ◽

10.3390/app11135793 ◽

2021 ◽

Vol 11 (13) ◽

pp. 5793

Author(s):

Bartosz Dominikowski

Keyword(s):

High Resolution ◽

Fuzzy Controller ◽

Automatic Gain Control ◽

Gain Control ◽

Measurement Range ◽

Power Converter ◽

Current Measurement ◽

Dc Power ◽

Programmable Gain ◽

Electric Loads

The accuracy of current measurements can be increased by appropriate amplification of the signal to within the measurement range. Accurate current measurement is important for energy monitoring and in power converter control systems. Resistance and inductive current transducers are used to measure the major current in AC/DC power converters. The output value of the current transducer depends on the load motor, and changes across the whole measurement range. Modern current measurement circuits are equipped with operational amplifiers with constant or programmable gain. These circuits are not able to measure small input currents with high resolution. This article proposes a precise loop gain system that can be implemented with various algorithms. Computer analysis of various automatic gain control (AGC) systems proved the effectiveness of the Mamdani controller, which was implemented in an MCU (microprocessor). The proposed fuzzy controller continuously determines the value of the conversion factor. The system also enables high resolution measurements of the current emitted from small electric loads (≥1 A) when the electric motor is stationary.

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