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Robotic arms have been used in various processes such as for moving goods, welding, assembling, and painting. In the case of welding and painting, it is necessary to move the end-effector robot accurately and smoothly to follow the specified trajectory. In robotic arm control, 2 things are important to be analyzed and implemented in controlling the motion of the robotic arm, namely inverse kinematic and trajectory planning. In this study, the inverse kinematic and trajectory planning algorithms are implemented to the robotic arm controller in the form of an Arduino Mega 2560 microcontroller. The inverse kinematic solution uses geometric and algebraic analytical methods. while the trajectory planning method is using LSPB (Linear Segment Parabolic Blend) Trajectory in Cartesian Space. Data retrieval is done by giving 2 input coordinates of the desired position and orientation, then the data in the form of the joint angle value will be measured using a rotary encoder as an angle sensor. Furthermore, the joint angle measurement value is converted in cartesian coordinates to get the end-effector position. Data analysis is done by comparing the data value of each joint angle with the calculated value so that the error value appears. The results showed that the inverse kinematic and trajectory planning algorithms were successfully applied to the 6-DOF robotic arm to perform straight-flat welding movements. Inverse kinematic testing on both input coordinates, the average error value for joints 2, 3, and 5 is 1.82º, 1.26º, and 2.08º. Meanwhile, the average error of the end-effector position at the x and z coordinates is 2.08 mm and 12.9 mm, respectively. Then for the trajectory planning test, the error value for the end-effector position in the x and z coordinates is 2.25 mm and 10.7 mm.

Pembangkit Listrik Tenaga Gas (PLTG) merupakan pembangkit dengan keunggulan waktu pengoperasian yang singkat dengan daya pembangkitan relatif besar. Dibalik kecepatan pembangkit tersebut untuk dioperasikan terdapat kelemahan yaitu tingkat efisiensi pembangkit yang tergolong rendah atau boros dalam penggunaan bahan bakar. Pada saat proses pengoperasian pembangkit di industri sering terjadi perubahan permintaan pasokan beban, untuk memenuhi permintaan tersebut pembangkit harus siap tertutama dalam ketersediaan bahan bakar. Permasalahan yang terjadi adalah PLTG tidak bisa dibebani daya maksimal karena sumber bahan bakarnya juga digunakan untuk bahan baku proses pokok industri. Penelitian ini bertujuan untuk mencari variasi temperatur inlet PLTG dengan besar nilai heat rate dan spesific fuel consumption (SFC) pada pola operasi PLTG yang paling optimal. Selanjutnya melakukan analisis keterkaitannya dengan efisiensi bahan bakar yang bisa dihemat di objek yang diteliti. Hasilnya dengan 39,7 % pembukaan katup gas dan temperatur masuk udara sebesar 30oC dan tekanan kompresi 7 bar menghasilkan nilai paling optimum dengan nilai SFC 0,627dan heat rate 8059.663 kcal/kWh. Pembukaan katup gas lain yaitu sebesar 42,9% pembukaan katup gas dan temperature masuk udara sebesar 30oC dan tekanan kompresi 7 bar menghasilkan nilai paling baik yaitu SFC 0.654 dan heat rate 8408.248 kcal/kWh.

Lead lithium alloy (Pb-17Li) is one of the candidate tritium breeders of fusion reactors. Lead bismuth eutectic alloy (LBE) is one of the candidate materials for the coolant of fast reactors and the target of accelerator driven systems. The functional layers such as an anti-corrosion layer and a tritium permeation barrier have been developed to be applied in these liquid metal systems. Zirconium oxide (ZrO2) are considered to be the candidate material of the functional layers due to its excellent chemical stability. The online monitoring of oxygen potential in the liquid metals is essential technology. The development of in-situ analysis technique for the layer properties in the liquid metals at high temperature is important issue. The purpose of the present study is to develop the on-line monitoring system for the oxygen potential and the layer properties both by the solid electrolyte (SE) oxygen sensor and the electrochemical impedance spectroscopy (EIS). The YSZ type SE sensor and the ZrO2/Zr specimen for the EIS were simultaneously immersed to liquid Pb at 698-898K. The responses of the oxygen sensor and the EIS were successfully obtained, and these signals indicated that the ZrO2 oxide layer is thermodynamically stable in liquid Pb. The EIS response was evaluated based on some equivalent circuit models as the oxide layer had a lot of horizontal cracks in its structure. The influence of the cracks on the capacitance is larger than that on the electrical resistance, when the covering ratio of the cracks in the layer is low. The influence on the electrical resistant becomes larger when the ratio is close to 100%.