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"Penelitian mengenai pendeteksian terhadap ruang terbatas proses pemesinan awal 5 Axis, merupakan salah satu bagian dalam pengembangan sistem CAM yang berbasis model faset 3D. Ruang terbatas dibedakan menjadi 2 bagian yaitu ruang terbatas terbuka dan ruang terbatas tertutup. Perbedaan ruang terbatas terbuka dan ruang terbatas tertutup yaitu perlunya orientasi pahat untuk proses pengerjaan ruang terbatas tertutup.Dalam penelitian ini pendeteksian ruang terbatas dilakukan dengan mendeteksi kebertumpukan segitiga dalam bidang x dan y dan perbedaaan arah vektor normal terhadap sumbu radius pahat. untuk mendapatkan hasil deteksi pahat pada ruang terbatas, penulis mengembangkan algoritma-algoritma dalam mengolah data yang berupa STL file. Metode yang telah dikembangkan ini kemudian di uji terhadap beberapa model produk dan mampu memberikan informasi mengenai adanya ruang terbatas dan areanya.

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The research concerning of bounded volume detection method for roughing process in multi-axis milling is one of a section to develop CAM system wich based on faceted model 3D. The bounded volume have 2 part wich very important, that is close boundary volume and open Boundary volume. The differences of open boundary volume and close boundary volume is tool oriented needed in machining process for close boundry volume.

In this research. Boundary volume will be get with detection of stacking of triangle and the differences of normal vector with normal angle of radius tool. To get bounded volume detection result, The writer develop algorithms to processing of STL file. The method which have been developed will be test to some models product and can give information regarding the existence of bounded volume area."

"Proses manufaktur memerlukan fungsi CAM yang dapat berinteraksi antara mesin dan computer, dimana visualisasi dari bentuk benda diperoleh dari software CAD . Dalam prosesnya dari sistem CAD memerlukan metode penghubung yaitu CAM agar mesin dapat berfungsi. Contohnya adalah mesin CNC (Computer Numerical Controlled). Perkembangan hingga saat ini sudah sampai tahap pemesinan 5 axis. Salah satu bagian penting dan harus ada dalam sebuah sistem CAM adalah pendeteksian dan penghindaran interferensi (gouging) antara pahat dengan model.Dalam penelitian ini, diimplementasikan metode pendeteksian dan penghindaran interferensi untuk pemesinan 5 axis. Banyak metode yang berkembang guna penyempurnaan 5-wris machining. Dan penelitian ini dikhususkan hanya pada kasus lekukan surface yang diindentifikasi sebagai ruang terbatas. Dalam pemesinan 5 axis, vektor orientasi mata pahat yang bergerak sepanjang lintasan pada sebuah material tidak hanya berposisi tegak sejajar sumbu z, namun vektor orientasi pahat sesuai dengan vektor normal titik dimana pahat bisa melakukan inklinasi pada kasus pemakanan bidang Iengkung (non planar) yang dimaksud dan mendeteksi bidang terbatas tertutup. Penelitian Iebih difokuskan bagaimana cara pahat untuk mendeteksi alur yang melengkung tersebut dan berinklinasi sesuai dengan bidang ye makanannya.

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Process of Manufacture needs CAM interaction function able to between and machine of computer, where visualization of object form obtained from CAD software. In course of him of system of CAD need link method that is CAM so that machine can function. The example is machine of CNC (Computer Numerical Control). Growth till in this time has until phase of machining 5 axes, One part of the important and there must be in a CAM system is detection and evasion of interference ( gouging) between chisel with modelIn this research, detection method implementation and evasion of interference for machining 5 axis. Much method expanding to utilize completion 5-axis machining. And this research is majored only at hollowing case of surface which identification as volume bounded. In machining 5 axis, vector orient peripatetic chisel eye as long as trajectory at a material do not only have parallel straightening position of z tinder, but orientation vector chisel as according to normal vector of dot where chisel can conduct inclination at tortuous area accrue case ( such non-planar) and detect area of closed bounded volume. Research more focused how to chisel to detect the tortuous path and inclination as according to it's accrue area."

"Sculptured surface machining technology is increasing its role in modern manufacturing. Products? surfaces become more complicated each day and require technology that is able to perform machining processes more accurately, precisely and take lesser time and cost. Nowadays, CAM helps so much on these matters. One of the difficulties in performing sculptured surface machining process is machining on feature which can not be reached by ordinary 3 axis machining process, called closed bounded volume (CBV).The thesis is discussing the development of algorithm that not only can analyze a model as a whole, but also can automatically detect CBV on a model, which is a 3D faceted model, through Paired Normal Vectors Bucketing (PNVB). And the algorithm also automatically generates tool path for multi axis roughing on the CBV. The algorithm development and the model analysis are worked based on faceted model in STL file format. As the result, the algorithm has successfully detected CBV in a complex-shaped model and listed the tool?s coordinates and orientations during machining process on the CBV."

"Model faset STL merupakan salah satu format CAD yang sering dipakai dalam industri manufaktur, namun file STL tidak memiliki informasi hubungan bentuk atau topologi apapun terhadap fitur dari model tersebut. Dalam penelitian ini dikembangkan sebuah metode identifikasi fitur dan pengaplikasiannya dalam proses pembuatan toolpath dari model faset semi-open impeller. Dimulai dari membaca file STL, membuat struktur data, proses identifikasi fitur impeller, daerah ruang lingkup (bounded volume) hingga proses pembuatan toolpath secara otomatis menggunakan fitur tersebut. Metode yang dikembangkan telah diimplementasikan ke dalam program dalam bahasa C++ dan dapat mengidentifikasi berbagai fitur impeller seperti blade, shroud, hub dan lain-lain pada impeller dan menghasilkan toolpath secara otomatis.

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STL file format is one of the most used CAD formats in manufacturing industry, but this format doesn’t contain any topological information about the relationships between features in it. This research developed a method to identify the features of semi-open impellers in such faceted models and to generate toolpath using that features. The method spans from reading the STL files, making data structure, identifying features, determining bounded volumes to generating toolpaths automatically using those features. The developed method is implemented to a program and able to reliably identify many features including blade, shroud, hub, etc of the impeller and able to generate toolpath automatically."

"Untuk mencapai proses efisiensi milling, salah satunya dengan menggunakan strategi pemesinan peripheral milling karena material removal rate (mrr) yang besar terutama bila diaplikasi pada permukaan planar. Peripheral milling menemukan banyak kendala saat mengerjakan jenis permukaan sculptured dan memerlukan bentuk tool khusus yang menyesuaikan bentuk permukaan. Selain itu upaya efisiensi dapat dilakukan dengan mengurangi setup tool pada setiap tahapan proses (single setup tool) dengan menggunakan parameter tool yang sama misalnya silindrical cutter. Namun peripheral milling menggunakan tool silinder pada permukaan sculptured memerlukan metode dan strategi khusus, karena akan menemukan banyak interference antara tool dengan permukaan tergantung pada parameter tool dan initial tool orientation-nya. Sehingga problem dalam menentukan metode dan strategi pemesinan peripheral milling pada sculptured surface menggunakan tool silinder menjadi menarik untuk diteliti lebih lanjut dan menjadi keterbaharuan dalam penelitian ini. Posisi tool pada setiap cc-point mengandung nilai Normal vector (N), Feed direction vector (F) dan Tool Vector (T). Penetilian ini menghasilkan mengembangkan metode inisial orientasi tool peripheral, metode pendeteksian dan penghindaran interference peripheral, metode inisialisasi area non-machinable peripheral, dan pengembangan strategi diantaranya startegi tool orientasi alternative peripheral, strategi penghindaran intereference, startegi milling area non-machinable peripheral, strategi efektifitas terhadap arah pemakanan, strategi end milling sebagai solusi milling area non-machinable dan terakhir startegi hybrid milling (gabungan peripheral dengan end milling) menggunakan single parameter tool. Hasil pengembangan metode dan strategi kemudian divalidasi dengan simulasi milling pada model uji sculptured surface. Setelah diaplikasi pada beberapa model uji sculpturedsurface berbasis model faset, membuktikan metode dan strategi pemesinan yang dikembangkan telah berhasil disimulasikan pada seluruh area sculptured surface.Hasilnya dipresentasikan dalam prosentase kemampuan peripheral milling dan hasil akhir berupa toolpath simulasi hybrid milling. Hasil pengembangannya pada metode dan startegi peripheral milling ini dapat dijadikan sebagai acuan pengembangan strategi milling 5-axis selanjutnya

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To achieve the milling efficiency process, one of them is by using a peripheral milling machining strategy because high of the material removal rate (mrr), especially when applied to a planar surface. Peripheral milling encountered many obstacles when working on sculptured surface types and required a special form of tool to adjust the surface shape. In addition, efficiency efforts can be made by reducing the setup tool at each stage of the process (single setup tool) by using the same tool parameters such as a cylindrical cutter. However, peripheral milling using the tool cylinder on the sculptured surface requires a special method and strategy, because it will find a lot of interference between the tool and the surface depending on the tool parameters and the initial tool orientation. So that the problem in

determining the method and strategy of peripheral milling machining on sculptured surfaces using tool cylinders becomes interesting for further research and becomes a novelty in this study. Tool position at each cc-point contains Normal vector (N), Feed direction vector (F) and Tool Vector (T) values. This research resulted in

developing initial peripheral tool orientation methods, detection and avoidance methods for peripheral interference, methods for identification non-machinable peripheral areas, and developing strategies including alternative orientation tool peripheral strategies, interference avoidance strategies, non-machinable peripheral area milling strategies, effectiveness strategies for feed direction, end milling strategy as a solution for milling non-machinable areas and finally hybrid milling strategy (combination of peripherals and end milling) using a single parameter tool. The results of developing methods and strategies were then validated by simulating milling on the sculptured surface test model. After being applied to several sculptured surface test models based on the faceted model, it was proven that the developed machining methods and strategies has been simulated successfully on the entire sculptured surface area. The results are presented in the percentage of peripheral milling capabilities and the final result is a hybrid milling simulation toolpath. The results of its development on this peripheral milling method and strategy can be used as a reference for the development of the next 5-axis milling strategy."

"Engineering design calculations for tank bottom sections, including direct current requirements and voltage calculations, followed by additional structures, such as electrical grounding systems, have already been successfully implemented and controlled in field conditions. Furthermore, the effect of soil resistivity in layers, oxygen content and the pH value of the soil against the disproportionate IR-Drop voltage, including its effect on potential distribution, have been already successfully observed. Other influences, such as the depth and location of the anode groundbed determination along with the establishment of impressed current cathodic protection related to the main tools and equipment, such as external corrosion control methods, have been defined as the most effective ways in order to control potential distribution against the additional structures. Persuant to the verification results from the site located at Marangkayu, East Borneo, it has been determined that high soil resistivity could cause error readings in accordance with the accumulation results of the true readings and the IR-Drop voltage, since under real conditions, the tank structure would have received less current flow from an anode compared to a lower result. Naturally, a low pH value from the soil would decrease soil resistivity and enhance potential distribution from the anodes to the tank structures. The results show that the cathodic protection required 10 additional anodes, (each one is of a tubular mixed metal oxide) with a DC supply at minimum amperage of 154 Amps and a minimum voltage supply of 32 Volts. During the research, it was identified that high soil resistivity above 3000 ohm-cm would cause error readings. Naturally, acidic soil is in the region of pH 5-7 value, which would decrease soil resistivity and enhance the potential distribution from the anode to the tank structure."

"Pemantauan keausan pahat pada proses pemesinan merupakan hal yang penting. Perambatan keausan pahat yang tidak normal maupun peristiwa rusaknya pahat sebelum masa pakai dapat mempengaruhi hasil pemesinan. Pada pemesinan micro-milling, keausan pahat terjadi jauh lebih cepat dibandingkan pada pemesinan macro-milling dikarenakan efek downsizing terhadap geometri pahat itu sendiri. Untuk hal tersebut, sebuah sistem pemantauan keausan pahat dapat memberikan informasi perambatan keausan pahat agar pengguna dapat mengantisipasi kejadian-kejadian yang destruktif serta dapat mengambil keputusan lebih lanjut atas proses pemesinan yang sedang berlangsung. Pada kerja penelitian ini telah dikembangkan sebuah sistem pemantauan keausan pahat untuk pemesinan micro-milling berbasis teknologi digital twin. Sistem yang dikembangkan mampu memberikan informasi estimasi keausan pahat serta informasi ketidakpastian estimasi itu sendiri dengan memanfaatkan simulasi real-time yang dijalankan dalam digital twin. Model virtual dikembangkan berdasarkan model mekanistik dari proses micro-milling yang merupakan bagian dari pendekatan berbasis hukum fisika (physics-based). Model virtual yang dikembangkan meliputi model motor spindle, model unit pengendali (controller) spindle, dan model torsi potong. Ketika simulasi digital twin berjalan, model virtual mensimulasikan variabel-variabel yang terkait proses pemesinan micro-milling serta berinteraksi dengan beberapa variabel lain yang diperbarui (di-update) berdasarkan data real-time sensor-sensor di mesin micro-milling. Variabel tersimulasi digital twin dijadikan informasi dasar untuk dibandingkan dengan variabel yang didapat secara real-time, khususnya variabel torsi motor spindle yang kemudian ditransformasi ke ruang keausan pahat. Extended Kalman filter (EKF) digunakan sebagai salah kerangka kerja untuk mengintegrasi informasi tersimulasi dan informasi real-time untuk menghasilkan sebuah estimasi keausan pahat. Proses pemantauan keausan pahat dilakukan dengan menggunakan diagram kendali (control chart) dan kategorisasi tingkat keausan pahat untuk mengevaluasi nilai estimasi keausan pahat dan ketidakpastian estimasi itu sendiri. Eksperimen pemesinan slot micro-milling dilakukan untuk benda kerja yang terbuat dari stainless steel SUS304 dengan menggunakan pahat mikro berbahan karbida berukuran diameter 1000 µm. Dengan menggunakan empat dataset yang dihasilkan dari eksperimen, sistem pemantauan yang dikembangkan mampu menunjukkan proses perambatan keausan pahat dengan rata-rata error estimasi terbesar adalah 0.052 mm dan nilai ketidakpastian estimasi σtruth terbesar adalah ±0.04 mm untuk dua mata pahat. Untuk implementasi menggunakan EKF, rata-rata error estimasi terbesar adalah 0.038 mm dengan standar deviasi terbesar adalah ±0.031 mm untuk dua mata pahat. Kerja penelitian ini juga telah menghasilkan sebuah alat pengukur keausan pahat yang disebut MicroEye dengan metode observasi langsung (direct observation) menggunakan kamera mikroskop dan lengan robot aktif 6-DOF (degree of freedom). Dalam hal kemampuan pengambilan gambar, MicroEye mampu membawa kamera ke posisi yang ditargetkan sehingga seluruh area keausan pahat yang ingin dideteksi berada dalam ROI (region of interest) dengan tingkat keberhasilan sebesar 86.66%. Dalam hal kemampuan mencapai posisi, MicroEye memiliki error posisi sudut maksimum sebesar 0.596◦ dan error posisi linear maksimum 0.0336 cm pada arah sumbu x dan 0.767 cm pada arah sumbu y.

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Tool wear monitoring is an essential aspect of the machining process. The tool breakage and the abnormality of tool wear progression affect the machining result. Due to the downsized tool’s geometry, the progression of tool wear in micro-milling is much faster than in macro-milling. A tool wear monitoring system helps to give information about the progression of tool wear so that the user can anticipate unwanted destructive events and make further decisions for the ongoing machining process. This dissertation presents the development of a tool wear monitoring system based on the digital twin technology for micro-milling applications. The developed system can provide the tool wear estimate and the estimation uncertainty altogether by running the real-time digital twin simulation. The virtual model was developed from the mechanistic model of the micro-milling process, which is part of a physics-based approach. The virtual model consists of the spindle motor, spindle controller, and cutting torque models. During the simulation, the virtual model simulates the variables of the micro-milling process and interacts with some of the real-time variables coming from the sensors in the micro-milling machine. The simulated variables (such as spindle motor torque) as the ground information are compared to the real-time variables in the wear space. Extended Kalman filter (EKF) is used as the framework to integrate the simulated and real-time information to estimate the wear growth. Then, the wear estimate and the estimation uncertainty are evaluated using a control chart and a categorization of wear level. The slot micro-milling experiment was conducted for SUS304 stainless steel workpiece with 1000 µm carbide micro-tool. The developed system can monitor the progression of tool wear with the largest mean of estimation error = 0.052 mm and the largest estimation uncertainty = ±0.04 mm. The implementation of EKF framework has improved the estimation accuracy with largest estimation error 0.038 mm with largest standard deviation ±0.031 mm for two cutting teeth. This dissertation also presents the result of a tool wear measurement device called MicroEye. The device uses a direct observation approach with a microscope camera as the primary sensor. The device has an active 6-DOF (degree of freedom) arm robot mechanism for motion flexibility. In terms of wear analysis, MicroEye can provide three metrics to analyze the difference between the fresh and the worn tools. In the aspect of image acquisition, MicroEye was able to bring the camera to the targeted position with the success rate 86.66% so that the ROI (region of interest) of the tool image is fully captured by the camera. In positioning, MicroEye achieved a maximum error of angular position 0.596◦, the maximum error of linear position 0.0336 cm in x-axis direction and 0.767 cm in y-axis direction."

"Beberapa tahun belakangan ini pengendali logika fuzzy muncul sebagai teknik alternatif dari pengendali klasik dalam suatu pengendalian proses. Hal ini disebabkan karena logika fuzzy mempunyai kemampuan yang baik sekali, kemungkinan ini disebabkan karena kefleksibelan dari proses pengambilan keputusan fuzzy, dan cocok untuk sistem dengan model matematis yang sangat sulit (tidak jelas); hanya kebiasaan umumnya saja yang diketahui [Gatl92]. Seiring dengan perkembangannya, diperkenalkan berbagai macam algoritma logika fuzzy seperti kendali logika fuzzy self organizing, kendali logika fuzzy adaptif dan fuzzy model reference learning control (FMRLC). Pada Skripsi ini dibahas mengenai simulasi penggunaan logika fuzzy dengan FMRLC sebagai pengendali kemudi pada kapal kargo. Secara umum pengendalian kemudi kapal kargo memakai pengendali logika fuzzy dengan proses "learning" ini, memberikan performance yang baik ketika berinteraksi dengan lingkungan serta perubahan dinamik dari kapal kargo tersebut seperti kecepatan kapal, keseimbangan, beban kapal, angin, anus dan gelombang yang menerpa kapal. Algoritma FNMC ini menggunakan suatu model referensi yang ditentukan sebelumnya sehingga performance umpan balik lingkar tertutup sistem berkelakuan sesuai dengan model referensi tersebut dengan mensintesa dan menala basis pengetahuan (knowledge base) kendali fuzzy. Hasil pengendalian dengan menggunakan logika fuzzy tersebut, disimulasikan untuk memperlihatkan kinerja dari pengendalian kemudi kapal kargo. Dalam analisa respons keluaran sistem dipakai parameter tanggapan waktu, yaitu rise time, settling time, peak time, percent overshoot dan galat tunak yang dibandingkan dengan parameter tanggapan waktu pengendali fuzzy biasa dan model referensi. Hasil analisa menunjukkan bahwa penerapan pengendalian menggunakan FMRLC dapat memperkecil rise time, settling time, peak time, percent overshoot dan galat tunak serta berkelakuan sesuai dengan model referensi."