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All Journal Jurnal Polimesin Indonesian Journal of Aerospace
Ramadhan, Redha Akbar
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Aerospace Engineering Astronomy Automotive Engineering Control & Systems Engineering Engineering Materials Science & Nanotechnology Mechanical Engineering

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Shear strength comparison of single lap and joggle lap adhesive joints in carbon fiber composites manufactured via vacuum-assisted resin infusion Pratama, Mikhael Gilang Pribadi Putra; Abdurohman, Kosim; Pratomo, Rezky Agung; Hidayat, Ryan; Ramadhan, Redha Akbar; Aritonang, Rian Suari; Nurtiasto, Taufiq Satrio; Ardiansyah, Riki; Nugroho, Afid; Nuranto, Awang Rahmadi; Wandono, Fajar Ari; Targani, Dudi; Ula, Nur Mufidatul
Jurnal Polimesin Vol 22, No 5 (2024): October
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v22i5.5437

Abstract

The extensive utilization of composite materials has spurred the advancement of diverse joining techniques suitable for components constructed from such materials. This study focuses on the examination of two specific types of joints: single lap and joggle lap joints. The specimens utilized were composed of unidirectional carbon fiber composite combined with vinyl ester resin, manufactured via the vacuum-assisted resin infusion method. Vinyl ester adhesives were employed in the bonding process, with the joint surfaces undergoing sanding treatment prior to testing. Mechanical testing was conducted on the specimens according to ASTM D5868 standard, employing a constant crosshead speed until failure occurred. The test results reveal that the shear strength of single lap joints surpasses that of joggle lap joints. Within the single lap joint configuration, a mixed failure mode comprising both adhesive and cohesive failure is observed. Conversely, in joggle lap joints, substrate delamination is prevalent, suggesting the predominance of peel stress during loading.
A Comparison of Vacuum Infusion, Vacuum Bagging, and Hand Lay-Up Process on The Compressive and Shear Properties of GFRP Materials Abdurohman, Kosim; Pratomo, Rezky Agung; Hidayat, Ryan; Ramadhan, Redha Akbar; Nurtiasto, Taufiq Satrio; Ardiansyah, Riki; P.P.P., Mikhael Gilang
Indonesian Journal of Aerospace Vol. 21 No. 1 (2023): Indonesian Journal of Aerospace
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/ijoa.2023.286

Abstract

Fiber-reinforced plastics are widely used in aerospace, marine, military, automotive, wind turbine, sports, and civil engineering applications. GFRP is a common material used in engineering applications such as for UAV structural material. Several techniques that can be used in the composite structure manufacturing process are HLU, VB, and, VARI. This paper studies the influence of the three manufacturing processes on the compressive and shear properties of GFRP composites. This study uses e-glass fiber as reinforcement material and a clear epoxy polymer called lycal as matrix material. The composites were manufactured by using HLU, VB, and VARI processes. The specimen dimensions, compressive, and shear tests are following ASTM standards. The microstructural characteristics were observed using a scanning electron microscope. The compressive strength of VARI composite is higher than HLU and VB composites up to 71% and 53%, respectively. The shear strength of the VARI composite is higher than HLU and VB composites up to 71% and 53%, respectively.
STABILITY AND CONTROLABILITY ANALYSIS ON LINEARIZED DYNAMIC SYSTEM EQUATION OF MOTION OF LSU 05-NG USING KALMAN RANK CONDITION METHOD Septiyana, Angga; Hidayat, Kurnia; Rizaldi, Ardian; Suseno, Prasetyo Ardi Probo; Jayanti, Eries Bagita; Atmasari, Novita; Ramadiansyah, M. Luthfi; Ramadhan, Redha Akbar
Indonesian Journal of Aerospace Vol. 18 No. 2 Desember (2020): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.jtd.2020.v18.a3318

Abstract

This paper discusses the stability, control and observation of the dynamic system of the Lapan Surveillance UAV 05-NG (LSU 05-NG) aircraft equation. This analysis is important to determine the performance of aircraft when carrying out missions such as photography, surveillance, observation and as a scientific platform to test communication based on satellite. Before analyzing the dynamic system, first arranged equations of motion of the plane which includes the force equation, moment equation and kinematics equation. The equation of motion of the aircraft obtained by the equation of motion of the longitudinal and lateral directional dimensions. Each of these equations of motion will be linearized to obtain state space conditions. In this state space, A, B and C is linear matrices will be obtained in the time domain. The results of the analysis of matrices A, B and C show that the dynamic system in the LSU 05-NG motion equation is a stable system on the longitudinal dimension but on the lateral dimension directional on the unstable spiral mode. As for the analysis of the control of both the longitudinal and lateral directional dimensions, the results show that the system is controlled.
NUMERICAL INVESTIGATION ON THE FUSELAGE AIRFRAME OF LSU 05 NG AIRCRAFT Hafid, M.; Nurrohmad, Abian; Ramadhan, Redha Akbar
Indonesian Journal of Aerospace Vol. 18 No. 2 Desember (2020): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.jtd.2020.v18.a3327

Abstract

In this paper, numerical investigation on the fuselage structure of LSU 05 NG was carried out. This fuselage is designed to carry the payload up to 30 kg. Statical numerical analysis using finite element method was done using Simulia Abaqus. The fuselage structure that has been design consists of frame, longeron, and skin that can also be semi-monocoque structure. This airframe use combination of balsa and GFRP type of composite as the material. There are three load case: take-off condition, cruise condition, and landing condition. Tsai-hill failure criteria is used to investigate the strength of the composite structure due to the load that applied. Maximum stress from this calculation is 48 Mpa at the ground condition (take-off and landing) while the cruise stress analysis is 16 Mpa. The maximum tsai-hill criterion is 0,83. With such simulation results it can be said that the fuselage structure is still safe when operated and can also be optimized for several components so that the weight of the aircraft can be reduced.
A FINITE ELEMENT ANALYSIS OF CRITICAL BUCKLING LOAD OF COMPOSITE PLATE AFTER LOW VELOCITY IMPACT Ramadhan, Redha Akbar; Suada, M. Giri; Syamsudin, Hendri
Indonesian Journal of Aerospace Vol. 18 No. 2 Desember (2020): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.jtd.2020.v18.a3328

Abstract

Composite is a material formed from two or more materials that macroscopically alloyed into one material. Nowadays, composite has been generally applied as lightweight structure of aircraft. This is due to the fact that composites having high strength-to-weight ratio. It means the composites have the capability to take on various loads, despite their lightweight property. Laminate composite is one type of composite that has been generally used in aircraft industries. This type of composite is susceptible to low-velocity impact induced damage. This type of damage can be happening in manufacture, operation, or even in maintenance. Low-velocity impact could cause delamination. Delamination happens when the plies of laminated composites separated at the interface of the plies. This type of damage is categorized as barely visible damage, means that the damage couldn’t be detected with visual inspection. Special method and tool would be needed to detect the damage. Delamination will decrease the strength of the laminated composite. Delamination can be predicted with numerical simulation analysis. With increasing capability of computer, it is possible to predict the delamination and buckling of laminated composite plate. This research presents the comparisons of buckling analysis results on laminated plate composite and damaged laminated plate composite. By the result of LVI simulation, it is shown that low velocity impact of 19.3 Joule causing 6398 mm2 C-Scan delamination area inside the laminated composite. The delamination causing structural instability that will affect buckling resistance of the plate. The result of analysis shows that the existence of delamination inside laminate composite will lower its critical buckling load up to 90% of undamaged laminate’s critical buckling load.
Co-Authors Abdurohman, Kosim Aritonang, Rian Suari Atmasari, Novita Hafid, M. Hidayat, Kurnia Hidayat, Ryan Jayanti, Eries Bagita Nugroho, Afid Nuranto, Awang Rahmadi Nurrohmad, Abian Nurtiasto, Taufiq Satrio P.P.P., Mikhael Gilang Pratama, Mikhael Gilang Pribadi Putra Pratomo, Rezky Agung Ramadiansyah, M. Luthfi Riki Ardiansyah, Riki Rizaldi, Ardian Septiyana, Angga Suada, M. Giri Suseno, Prasetyo Ardi Probo Syamsudin, Hendri Targani, Dudi Ula, Nur Mufidatul Wandono, Fajar Ari