3 sonuçlar
Arama Sonuçları
Listeleniyor 1 - 3 / 3
Yayın A new local path planning approach by synthesis of PRM and RRT* algorithms for an autonomous mobile robot(Springer, 2025-02) Göktaş, Anıl Gökhan; Sezer, SemihMany research efforts have been and continue to be carried out to make human life easier through the use of new technologies. The ability to shift labor to non-humans and reduce the workforce demonstrates the scope of innovation. In this investigation, a new approach is proposed to address several shortcomings of the PRM and RRT algorithms used for path planning in mobile robots. The proposed approach differs by building markers around it, avoiding dynamic obstacles and providing a shorter path. Simulation studies of the PRM and RRT* algorithms, along with the Circular Nodes (CN) approach, were conducted in real and virtual environments. Meanwhile, experimental studies for the CN approach were carried out in a real environment, with obstacles. When compared to other methods, the proposed approach has demonstrated an increase in node efficiency by up to five times. Moreover, implementing node points that are approximately 10% of those used in the PRM and RRT* algorithms has resulted in a shorter path. The reduction in the number of nodes and path length leads to a reduction in energy consumption and processing power.Yayın Effect of mechanically exfoliated graphite flakes on morphological, mechanical, and thermal properties of epoxy(Multidisciplinary Digital Publishing Institute (MDPI), 2024-11-11) Gül, Ayşenur; Kamali, Ali RezaCarbon-reinforced polymer composites form an important category of advanced materials, and there is an increasing demand to enhance their performance using more convenient and scalable processes at low costs. In the present study, graphitic flakes were prepared by the mechanical exfoliation of synthetic graphite electrodes and utilized as an abundant and potentially low-cost filler to fabricate epoxy-based composites with different additive ratios of 1–10 wt.%. The morphological, structural, thermal, and mechanical properties of these composites were investigated. It was found that the thermal conductivity of the composites increases by adding graphite, and this increase mainly depends on the ratio of the graphite additive. The addition of graphite was found to have a diverse effect on the mechanical properties of the composites: the tensile strength of the composites decreases with the addition of graphite, whilst their compressive strength and elastic modulus are enhanced. The results demonstrate that incorporating 5 wt% of commercially available graphite into epoxy not only raises the thermal conductivity of the material from 0.223 to 0.485 W/m·K, but also enhances its compressive strength from 66 MPa to 72 MPa. The diverse influence of graphite provides opportunities to prepare epoxy composites with desirable properties for different applications.Yayın Energy-based characterization of drilling-induced residual stresses in AA7075-T6(Multidisciplinary Digital Publishing Institute (MDPI), 2026-01) Tok, Görkem; Dinçer, Ammar Tarık; Bakkal, Mustafa; Kuzu, Ali TanerThis study examines the influence of drilling parameters on thrust force, torque, active work, and axial residual stress formation in hot-forged and T6-treated AA7075, a critical high-strength aluminum alloy. A full factorial design was applied using three spindle speeds (800, 1000, 1200 rpm) and three feed rates (0.05, 0.10, 0.15 mm/rev). Cutting force and torque signals were measured using a dynamometer, and axial residual stresses were determined by X-ray diffraction at two locations along the hole depth, namely, the hole entrance (Point A) and the hole exit (Point B). The results show that feed rate is the dominant factor influencing drilling mechanics and residual stress formation, whereas spindle speed mainly affects the thermal and frictional conditions governing stress relaxation. A consistent asymmetry was observed between the two measurement locations, with the exit side exhibiting stronger stress relaxation behavior associated with breakthrough mechanics. Finally, the relationship between active work and axial residual stress is discussed using a qualitative, energy-based interpretation, highlighting active work as a physically meaningful indicator for drilling-induced residual stress evolution.
