ANALISIS KESALAHAN FUNGSI RESPON FREKUENSI AKIBAT KETERBATASAN WAKTU REKAM PADA PENGUJIAN GETARAN DENGAN EKSITASI IMPAK KASUS DOMAIN WAKTU KONTINU

This paper derives mathematical equation describing the relation between errors in FRF due to limited record time length, record time and the time constant of a vibration system modelled by the I- dof vibration system with viscious damping. It is assumed in derivation of the equations that both impact excitation as well as response signals are not contaminated by noises. Moreover, the impact excitation is assumed to be a delta Dirac function. Consequently, the spectrum of the excitation is constant for all frequencies. The derived mathematical equations results show that the FRF error is a complex function so that is can be expressed by the magnitude anf phase functions. The magnitude of FRF error represent the maximum possible error occuring in the FRF magnitude. The maximum possible error occuring in the FRF magnitude at fn is influenced by parameters, such as record time and time constant of the structures. This maximum possible error shows an exponentially decreasing nature as the ratio of these parameters increases. Based on the derived equation, a recording of the response signal within three times of the system time constant results in the maximum possible error at fn in the FRF magnitude in the order of 5% of the theoritical FRF magnitude. Such recording can be performed if the peak amplitude of the response signal ceases to about 5% of the initial peak amplitude at the end of the record time for between 0.001 and 0,1

Implementation consensus algorithm and leader-follower of multi-robot system formation

Robot technology has recently been applied to many applications to help human activities. Mobile Robot is one of the most flexible robot technology. This research uses a mobile robot designed using an omnidirectional wheel for the movement mechanism. Coordination and control of multi-robots can be assigned to perform any task from a different kind of field. Therefore, this paper aims to develop a multi-robot system to form a formation to do the task. The multi-robot system consists of three units Mobile Robot. The formation system will be built based on a coordinate point determined by a consensus point. The leader-follower topology is used to determine the orientation of the robot. ROS (Robot Operating System) is used as middleware to create a multi-robot system. The Open Base package in Gazebo Simulator is also used to simulate the movement of the multi-robot. From three test scenarios, this research results show that all the robots can do and follow the tasks simulated in the Gazebo with an average accuracy of 88.14%. Furthermore, no feedback from the robot to the Gazebo Simulator affects the robot's accuracy average below 90%.

Implementation consensus algorithm and leader-follower of multi-robot system formation

Robot technology has recently been applied to many applications to help human activities. Mobile Robot is one of the most flexible robot technology. This research uses a mobile robot designed using an omnidirectional wheel for the movement mechanism. Coordination and control of multi-robots can be assigned to perform any task from a different kind of field. Therefore, this paper aims to develop a multi-robot system to form a formation to do the task. The multi-robot system consists of three units Mobile Robot. The formation system will be built based on a coordinate point determined by a consensus point. The leader-follower topology is used to determine the orientation of the robot. ROS (Robot Operating System) is used as middleware to create a multi-robot system. The Open Base package in Gazebo Simulator is also used to simulate the movement of the multi-robot. From three test scenarios, this research results show that all the robots can do and follow the tasks simulated in the Gazebo with an average accuracy of 88.14%. Furthermore, no feedback from the robot to the Gazebo Simulator affects the robot's accuracy average below 90%.

Pattern recognition based movement control and gripping forces control system on arm robot model using LabVIEW

Most arm robot has an inefficient operating time because it requires operator to input destination coordinates. Besides, main problem of arm robot is object’s vulnerability when it is manipulated by the robot. This research goals is to develop an arm robot control system which has ability to automatically detect object using image processing in order to reduce operating time. It is also able to control gripping force for eliminating damage to objects caused by robot gripper. This research is implemented in LabVIEW 2011 software to control arm robot model which can represent industrial scale robot. The software is designed with informative visualization to help user learn and understand robotic control concept deeply. The system can automatically detect object position based on pattern recognition method which has four steps: pre-processing process to initialize picture taken by camera, segmentation process for separating object from the background, classification process to determine characteristics of object, and position estimation process to estimate object position in the picture. The object’s position data are then calculated by using kinematic equation to control the robot’s motion. The results show that the system is able to detect object and move the robot automatically with accuracy rate in x-axis is 95.578 % and in y-axis is 92.878 %. The system also implements modified PI control method with FSR as input to control gripping force with maximum overshoot value `10 %. Arm robot model control system developed is successfully meet the expectation. The system control can be implemented to industrial scale arm robot with several modification because of kinematic similarity between model and industrial scale robot

RANCANG BANGUN GRAPHICAL USER INTERFACE PADA SISTEM KENDALI SUHU NIRKABEL PEMANAS TANGKI BERPENGADUK KONTINYU

Pemanas memiliki peran penting dalam proses industri dalam meningkatkan efisiensi proses dan menghasilkan kualitas produk yang baik, salah satunya adalah pemanas tangki berpengaduk kontinu. Masalah yang sering dihadapi dalam proses pemanasan adalah keakuratan suhu pada tangki pemanas. Agar suhu tangki tersebut mencapai titik setel dengan kecepatan respon dan akurasi yang tinggi, maka diperlukan sebuah pengendali. Pengendali PID merupakan salah satu jenis pengendali yang paling banyak digunakan oleh 90% industri karena sederhana, mudah diterapkan dan digunakan, serta fungsionalitas yang jelas. Oleh sebab itu, mahasiswa perlu didukung dengan media pembelajaran interaktif pada sistem kendali suhu pemanas tangki berpengaduk kontinu untuk meningkatkan kemampuan dan kompetensinya. Artikel ini membahas rancangan graphical user interface pada model sistem pemanas tangki berpengaduk kontinu menggunakan sistem kendali dan antarmuka interaktif sebagai alat bantu pembelajaran. Model ini menggunakan LabVIEW 2017 sebagai sofware virtual instrument dan NI ELVIS II sebagai perangkat keras pengendali serta akusisi data sistem. Skema kendali yang digunakan adalah PID konvensional dimana pengguna dapat menentukan parameter PID. Selain itu, antarmuka dibuat dengan konsep interactive learning, dimana proses pembelajaran berpusat pada pengguna aplikasi. Pengguna dimaksudkan untuk berkesperimen menggunakan antarmuka sistem pemanas tangki berpengaduk kontinu untuk mempelajari pengaruh perubahan parameter pengendali PID dan parameter fisik terhadap respon sistem