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Perancangan Autonomous VTOL pada Quadcopter dengan Menggunakan Feedback Linearization dan Fuzzy Takagi-Sugeno
Get PDFQuadcopter merupakan salah satu jenis Unmanned Aerial Vehicle (UAV) yang banyak digunakan sebagai objek penelitian saat ini. Dengan empat rotor sebagai penggerak utama, quadcopter mampu bergerak secara rotasional dan translasional. Kedua sistem gerak ini secara matematis tergolong nonlinier dan tidak stabil. Dalam penelitian ini, dirancang autonomous Vertical Take-Off and Landing (VTOL) dengan membagi sistem quadcopter berdasarkan sistem geraknya, yaitu sistem gerak rotasi dan sistem gerak translasi. Masing-masing sistem gerak dikendalikan dengan kontroler yang berbeda.
Sebagai inner-loop dalam sistem quadcopter,sistem gerak rotasi dituntut memilikisettling timelebih cepat dari dari sistem gerak translasi yang merupakan outer loop.Input-state feedback linearizationdigunakan untuk mengatasi permasalahan tersebut.Kontroler dirancang melalui pendekatan model referensi yang diperoleh dengan mengatur letak pole dominan yang dinginkan. Dengan persamaan Input-state feedback linearizationyang diperoleh, sifat nonlineritas dan interaksi dalam sistem dapat dieliminasi.
Permasalahan tracking dalam sistem gerak translasi diatasi dengan menggunakan fuzzy Takagi-Sugeno. Sistem direpresentasikan kembali sebagai aturan fuzzy dengan titik operasi sebagai variabel premis dan model linier sebagai konsekuen. Dengan variabel premis yang sama, kontroler dirancang dengan skema Parallel Distributed Compensation (PDC). Nilai penguat kontroler yang mampu menjamin kestabilan sistem dan memenuhi performa H∞ diperoleh dengan bantuan Linear Matrix Inequality (LMI).
Hasil simulasi dengan MATLAB menunjukkan bahwa sistem kontrol gerak rotasi yang dirancang mampu menstabilkan sudut roll, pitch dan yaw di 0 rad. Kontrol trackingpada altitude mampu menjamin kestabilan sistem dan membuat respon altitudemengikuti sinyal referensi yang diberikan. Selain itu, sistem kontrol juga mampu mengatasi gangguan yang diberikan dengan nilai L2gain sebesar 0.000539. Artinya, L2gain lebih kecil dari level pelemahan yang ditentukan yaitu sebesar 0.003. Hal ini menunjukkan bahwa performa H∞ telah terpenuhi.
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Quadcopter is a
n
Unmanned Aerial Vehicle (UAV) that is frequently used
as an object of study now. Its
four rotors that is the main drive, let quadcopter move
in rotation and translation. Both of this motion systems are unstable dan
matematically nonlinear. In this study, we have designed an a
utonomous
Vertical
Take
-
Off and Landing
(VTOL) by dividing quadco
pter system based on its motion
systems, i.e. rotation motion system and translation motion system. Each motion
system is controlled by different controller.
As the inner
-
loop
in quadcopter system, rotation motion system is forced
to have a settling time
t
hat is faster then the translation motion system as the outer
loop
.
Input
-
state feedback linearization is used
tosolve
this problem
. Reference
models are obtained by set the dominant pole. Using state feedback equation that
was obtained, nonlinearity and
interaction inside the system can be eliminated.
Tracking problem on translation motion system is solved by using fuzzy
Takagi
-
Sugeno. System is represented by fuzzy rules with operating points as
premise variable and linear models as consequent. By using
the same premise
variable,
the controller is designed based on Parallel Distributed Compensation
(PDC) scheme. The appropriate controller gain which can
stabilize system and meet
the H
∞
performance is obtained with the help of Linear Matrix Inequality (LMI).
Simulation results with MATLAB show that the control system have been
designed can stabilize
rotation motion system at 0 rad. Altitude tracking contro
l
can
make the semi
-
global stabil system guarantedand altitude response is able
to track
the given reference signal. In addition, the control system is able to attenuate the
given bounded disturbance signal with
L
2
gain
is about 0.000539
. Its mean
L
2
gain
i
s less than the prescibed
attenuation level which is 0.003
.
This shows that the
H
∞
performance is met
Perancangan Sistem Kontrol Level Nonlinier Menggunakan Fuzzy-PID Supervision
Get PDFSistem level merupakan sistem yang banyak ditemukan di industri. Sistem ini dapat dikategorikan sebagai sistem nonlinier karena dinamika dan deadtime yang dimilikinya. Salah satu karakteristik dari sistem ini adalah perubahan dinamika ketika set-point yang diberikan berubah. Akibatnya, kontroler PID konvensional dengan parameter tetap tidak mampu mengendalikan sistem ini dengan baik. Perlu dilakukan tuning ulang pada kontroler PID untuk menyesuaikan perubahan dinamika. Dalam paper ini, kami merancang sistem kontrol level menggunakan PID dengan parameter yang disupervisi oleh kontrol fuzzy. Sebagai kontroler utama, PID dirancang menggunakan metode Direct Synthesis (DS) untuk semua titik kerja yang ditentukan. Kontrol fuzzy dirancang berdasarkan nilai-nilai parameter PID yang diperoleh dari perhitungan metode DS. Hasil rancangan disimulasikan menggunakan software MATLAB. Simulasi menunjukkan bahwa sistem kontrol level hasil rancangan mampu mencapai set-point yang diberikan dengan settling time ts (±5%) berkisar antara 4 s.d. 6,5 detik, zero overshoot dan zero offset. Perbandingan dengan sistem kontrol PID konvensional juga menunjukkan hasil yang baik. Sistem kontrol level hasil rancangan rancangan mampu menjamin respon yang memenuhi performa zero overshoot dan zero offset
RANCANG BANGUN SOFTWARE PERHITUNGAN UNTUK SISTEM METER TURBIN DENGAN METODE FUZZY
Get PDFCustody transfer is an important activity in the oil and gas industry which requires high accuracy. In keeping the metering system in an accurate condition, dynamic testing is needed as an evaluation of the custody transfer metering system. In carrying out dynamic testing, software is needed so that calculations will be more accurate and minimize errors. Calculation software in the market is currently quite expensive and does not cover all the calculation needs needed in the field, it is necessary to make calculation software that suits your needs and has a low price. With this software, it is hoped that it can simplify the calculation process and speed up troubleshooting time when there is a measurement deviation because the data read in the flowcomp can be directly proven for its accuracy. In finding a correction factor, a method is needed that is able to determine the value between two known values. Fuzzy method is considered capable of solving these problems. Sugeno fuzzy method is suitable for use in this study because it has an output in the form of a constant. After testing several random samples, the results of the Sugeno fuzzy method have the greatest error on the MPMS API table, namely 0.00004. When compared with the interpolation method, the fuzzy method has the same results as the value generated by the interpolation method. So it can be concluded that the fuzzy method can be used as a calculation method in finding the correction factor
Pengujian Sistem Pengendalian Temperatur pada Prototipe Heat Exchanger Berbasis PID
Get PDFThe design of a PID-based heat exchanger temperature control system means controlling the temperature of the cold water output of the heat exchanger that has been designed to match the set point value through PID (Proportional Integral Derivative) controller mode control. Temperature control is carried out by controlling the flow rate of hot water. When the set point of the heat exchanger cold water temperature is increased, the servo valve opens more so that the hot water flow rate increases. The system interface is done through Delphi 7 software which displays the display of numbers and graphs of the received process data. The PID controller mode parameter value is obtained through trial and error method. As a comparison, the ideal PID calculation is carried out using the direct synthesis method to be applied to the calculation of system control in the Arduino microcontroller. The ideal PID calculation requires bump test results from each process variable. The results of data analysis and interface graphs show that an increase in the set point from 25℃ to 32℃ at the temperature of the heat exchanger output water causes the servo valve opening to approach full opening and is in a hunting system condition when the temperature has reached the set point. From the test results obtained Time Constant 89.744 seconds, Settling Time 127.232 seconds and Rise Time 127.8 seconds.Rancang bangun sistem pengendalian temperatur heat exchanger berbasis PID artinya mengendalikan temperatur air dingin keluaran heat exchanger yang telah dirancang agar sesuai dengan nilai set point melalui pengendalian mode controller PID (Proportional Integral Derivative). Pengendalian temperatur dilakukan dengan melibatkan pengendalian laju aliran air panas. Ketika set point temperatur air dingin heat exchanger dinaikkan maka servo valve semakin membuka sehingga laju aliran air panas bertambah. Software Delphi 7 digunakan untuk menampilkan hasil berupa angka dan grafik dari data proses sistem pengendalian temperatur. Nilai parameter mode kontroler PID didapat melalui metode trial and error. Sebagai pembanding, dilakukan perhitungan PID ideal menggunakan metode direct synthesis untuk diterapkan pada kalkulasi pengendalian sistem di dalam mikrokontroler Arduino. Perhitungan PID ideal memerlukan hasil bump test dari masing–masing variabel proses. Hasil analisis data dan grafik interface menunjukkan bahwa kenaikan set point dari 25℃ menjadi 32℃ pada temperatur air keluaran heat exchanger mengakibatkan bukaan servo valve mendekati bukaan penuh dan berada pada kondisi hunting system saat temperatur telah mencapai set point. Dari hasil pengujian diperoleh Time Constant 89,744 detik, Settling Time 127,232 detik dan Rise Time 127,8 detik
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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