Nonconventional Technologies Review

A word from our Editor-in-Chief

2025-12-30T18:35:28+00:00

Dimensional processing technologies known as "Concentrated Energy Processing Technologies", "Nonconventional Technologies" or "Alternative Technologies" can be characterized by exceptional dynamics of use, perhaps the highest of all technologies applied in machine building. Practically, these new technologies have gone through all the phases from their "invention" to their wide industrial use in only about 65 years, currently becoming alternative technologies, complementary to classical technologies.

OHS RISK ASSESMENT IN THE EDM PROCESS

2025-12-30T18:35:28+00:00

This paper evaluates occupational health and safety (OHS) risks in the electrical discharge machining (EDM) process and examines how different operational scenarios affect these risks. Building on a previous study, four scenarios were tested to determine the most efficient setup in terms of machining time, material removal rate (MRR), and electrode wear rate (EWR), and the most favourable one was identified. The methodology includes mapping the EDM process flow, linking activities to potential risks, assessing probability and severity using a risk matrix, and proposing preventive measures to reduce hazards. The study highlights the scenario that best balances efficiency and safety, demonstrating that proper risk management can optimize employee well-being.

CONTRIBUTIONS TO THE MODELING AND SIMULATION OF A BIPED WALKING ROBOT

2025-12-30T18:35:27+00:00

This study presents the modeling and simulation of a biped walking robot using MathWorks® simulation tools. The project focuses on developing a parametric and dynamic model that accurately represents the mechanical structure, joint kinematics, and actuator behavior of a bipedal robot. The methodology involves 3D modeling of the robot’s components, simulation of foot–ground contact forces, and comparative analysis of different actuation strategies—motion-based, torque-driven, and motor-based systems. By integrating mechanical, electrical, and control subsystems, the study evaluates trade-offs between model fidelity and simulation speed. Results indicate that while motor-actuated models provide higher physical realism, they significantly increase computational complexity. The work also highlights the importance of appropriate damping, force modeling, and control architecture (PID) for ensuring stable gait dynamics. Future developments include hardware implementation, enhanced actuator modeling, and machine learning approaches for optimizing walking performance.

FEASIBILITY STUDY OF POLYMER-BASED BENDING DEVICES MANUFACTURED VIA MATERIAL EXTRUSION ADDITIVE MANUFACTURING FOR SMALL-BATCH PRODUCTION AND PROTOTYPING

2025-12-30T18:35:27+00:00

This research explores the technical viability of utilising Material Extrusion (MEX) Additive Manufacturing (AM) technology for the fabrication of bending devices. The primary objective of this undertaking is to investigate the potential for decreasing production costs and accelerating lead times. The present study builds upon the findings of earlier investigations by means of an examination of the performance of polymer-based devices, which had previously been subjected to finite element analysis (FEA). The method advances the field by using a polymer-based die. The findings suggest that this method has potential application in small-batch production and prototyping, with a consistency between the experimental results and the predictions made via finite element analysis.

MODERN APPLICATION OF INERT OPEN-CELL POROUS CERAMIC MATERIALS FOR DESIGNING NON-CONVENTIONAL SELF-ASPIRANTING BURNERS

2025-12-30T18:35:26+00:00

The paper refers to the application of inert porous ceramic materials with large open pores in the construction of porous burners, capable of contributing to increasing the combustion stability, increasing the combustion speed, and reducing nitrogen oxide emissions (NO and NO₂). Two categories of porous ceramic materials were considered adequate for this purpose. A glass foam obtained by expansion of the glass waste and coal fly ash used the capacity of SiC as an expansion product to produce the suitable permeable body for the burning area of fuel-air mix. The method for making this porous piece had a special character of originality, the sintering/expanding heating being obtained through an own unconventional microwave heating technique, preponderantly direct and partially indirect. The porous ceramic piece for the combustion zone was procured from Germany. Testing the burner equipped with the two ceramic pieces confirmed the viability of the innovative solution.

GEOPOLYMER COMPOSITE MADE THROUGH PARTIAL REPLACING FLY ASH AND SLAG WITH CHEAPER AND LESS USED WASTE PRECURSORS

2025-12-30T18:35:26+00:00

The research presented in this paper was focused on making a geopolymer composite characterized by the large replacement of the most commonly used alumina-silicate precursors (carbon ash and processed metallurgical slag) with cheaper and less commonly utilized wastes. Thus, clay brick waste, residual building concrete, and flat glass waste resulted from building demolition were introduced in manufacturing mixture after reducing the carbon ash and slag content. Many previous works in the literature have confirmed that carbon ash and metallurgical slag are the most suitable industrial secondary products usable in the preparing process of geopolymer composites, but their intense demand has contributed to the trend of increasing their price. Numerous alternative materials with cementitious and pozzolanic properties available in the world offer the possibility of using them for similar purposes. Even if applying these wastes does not result in reaching the qualitative level of carbon ash/slag-based geopolymer, their appropriate combination is beneficial and the current work used different experimental versions including clay brick, residual concrete, and flat glass resulted from building demolition, associated with significantly reduced consumption of ash and slag.

ON SOME ASPECTS OF THE EVOLUTION OF NONCONVENTIONAL TECHNOLOGIES IN THE LAST DECADE

2025-12-30T18:35:25+00:00

The historical beginning of nonconventional technologies in Romania can be appreciated as the year 1954, when the Institute of Electrotechnical Research, created under the auspices of the Ministry of Electric Energy, was established in Timisoara. That's when the foundations were laid for the creation of the first Electrotechnologies laboratory in Romania at the Department of mechanical technologies (TM), UP Timisoara. After 20 years, the Center for Research in Nonconventional Technologies was established at the "Traian Vuia" Polytechnic Institute in Timisoara. In this paper, some references are made on the evolution of nonconventional technologies in Romania, with an emphasis on some developments from the last 10 years. Some novelties regarding modern applied technologies, based on energy concentration, such as 3D printing using metal powders, ultrasonic welding, are addressed in more detail. Some registered and certified invention patents in the field of nonconventional technologies are also recorded.

CO2 CAPTURE AND STORAGE IN CONCRETE GENERATED THROUGH EARLY-AGE CABONATION OF CALCIUM SILICATE HYDRATE

2025-12-30T18:35:25+00:00

Recent global research on the sequestration and definitive storage of CO₂ into concrete due to untimely carbonation of hydrated Ca₂SiO₄ (known as C-S-H), the most important phase of ordinary cement, has piqued the interest of authors of this paper. Limiting the gas footprint released into the atmosphere remains a very topical objective in the world and implicitly, also of the authors. Sodium bicarbonate (NaHCO₃) added into starting mix as a partial substitute for cement has already been identified as the suitable option to reach the objective. Another very interesting effect has been experimentally highlighted in the direction of increasing the mechanical resistance particularly, at an early-age of the concrete preparation. Specific measurements carried out after only 6 hours has found very high values of compression and flexural strength, close to the values corresponding to the end of concrete curing process of 28 days. This procedure has not yet been finalized in technological terms in the world. Its importance lies in the possibility of manufacturing without CO₂ emissions and utilizing the traditional Portland cement as the main binder for construction concrete in the current situation of world environmental crisis.

MANAGERIAL PERSPECTIVES ON BUILDING MAINTENANCE THROUGH THE INTEGRATION OF NONCONVENTIONAL TECHNOLOGIES AND INNOVATIVE SOLUTIONS

2025-12-30T18:35:24+00:00

Building maintenance is undergoing a profound evolution, thanks to the integration of innovative technological solutions. The use of drones equipped with optical and thermal sensors, capable of integrating RGB imaging with infrared thermography and generating elaborate 3D models, opens new perspectives for the diagnosis and optimization of buildings. This method is not limited to the rapid detection of hidden defects and monitoring of energy performance, but also leads to a reduction in costs and risks associated with conventional inspections. At the same time, by detecting energy losses and improving decision-making, RGB-T 3D technology contributes to extending the lifespan of buildings and reducing carbon emissions. The paper analyzes the transition from the visible to the infrared spectrum, practical scenarios for using drones in audits and maintenance processes, but also the current limitations of these tools. Finally, the potential of three-dimensional aerial thermography to become a key element in modern building maintenance management is highlighted, with direct advantages for sustainability and the development of a more efficient and environmentally responsible built environment

SUBMERGED FRICTION STIR PROCESSING OF EN AW 7075 ALUMINUM ALLOY

2025-12-30T18:35:24+00:00

Friction stir processing is a process for processing metallic materials that aims to locally modify the microstructure and mechanical properties. Submerged friction stir processing aims to limit the process temperature by using a liquid working medium, so as to avoid thermal overloading of the processing tool and the materials to be processed. The paper presents experimental research carried out at ISIM Timisoara on submerged friction stir processing for the 5mm thick EN AW 7075 aluminum alloy. Processing experiments were carried out in single pass and in multiple passes, with positive results. The evaluation program of samples/test pieces taken from the processed materials included visual examination and penetrating radiation, macro- and microscopic structural analyses, as well as mechanical tensile and bending tests.

LEVERAGING UNCONVENTIONAL TECHNOLOGIES AND INNOVATIVE SOLUTIONS FOR PROCESS OPTIMIZATION IN KNOWLEDGE-BASED ORGANIZATIONS

2025-12-30T18:35:23+00:00

This paper aims to provide an in-depth analysis of how unconventional technologies and innovative solutions can play a crucial role in enhancing process quality within knowledge-based organizations. Facing the challenges brought by rapid digital transformation, these organizations need to optimize interconnected workflows while ensuring transparency, traceability, and compliance to international standards. Emerging technologies such as advanced Robotic Process Automation (RPA), Internet of Things (IoT), blockchain, and collaborative digital platforms offer novel and effective ways to automate processes, enable real-time monitoring, and manage information intelligently. The study proposes an integrated conceptual framework that combines these unconventional technologies with innovative methods to boost operational efficiency, significantly reduce human errors, and enhance organizational flexibility and resilience. Additionally, it discusses the concrete challenges encountered during adoption—including technical, cultural, and managerial barriers—and offers practical strategies to overcome them. The findings deliver valuable recommendations for implementing and scaling these digital solutions, ultimately supporting sustainable performance and a continuous innovation culture in knowledge-driven environments.

OPTIMIZING THE SCAR PROCESS THROUGH NONCONVENTIONAL METHODS: APPLYING VIBRODIAGNOSTICS AND GENETIC ALGORITHMS FOR QUALITY IMPROVEMENT IN THE AUTOMOTIVE CHAIN

2025-12-30T18:35:23+00:00

This paper explores the application of unconventional methods to optimize the Supplier Corrective Action Request (SCAR) process. The study proposes an innovative framework that integrates vibrodiagnostics for the early detection of defects at the source and genetic algorithms for optimizing supplier process parameters. Through case study analysis, the paper demonstrates how these technologies can identify root causes of non-conformities that remain undetected by traditional methods, leading to more precise corrective actions and durable quality improvements. The results indicate a significant reduction in the recurrence rate of defects and an increase in the overall efficiency of the supply chain.