After more than a decade of progress towards Industry 4.0, digitalization continues its steady advance, particularly with regard to the modernisation and digital transformation of existing production facilities. The t...
After more than a decade of progress towards Industry 4.0, digitalization continues its steady advance, particularly with regard to the modernisation and digital transformation of existing production facilities. The targeted use of methods and tools enables systematic planning of a networked factory that takes numerous framework conditions into account. This in turn contributes to the successful fulfilment of operational goals as well as social and economic functions between the physical and virtual worlds. In the course of the digital transformation process, new types of systems are emerging that are becoming more complex, interactive, autonomous and powerful. With the help of cyber-physical systems, physical devices and processes can be equipped with computing and networking capabilities and connected to a data and knowledge structure that is ultimately integrated into the manufacturing process. Manufacturing processes are optimised and adapted through the use of algorithms for big data and advanced technologies. In this dynamic development, self-adaptive, self-learning and autonomous systems can help to successfully overcome the challenges of rapid technological progress and increasing product *** convergence of information technologies and operational technologies is essential to achieve the goal of digitalization in existing industries. This paper provides an overview of digitalization methods in factory planning in the context of Industry 4.0. It describes the common technologies and methods that have been developed over the course of more than a decade of continuous progress in Industry 4.0 and digitalization. A particular focus is placed on the Brownfield and Greenfield approach, which was introduced to software development by Hopkins and Jenkins in 2008. Using these approaches, possible advantages and disadvantages as well as hurdles and challenges in the integration of new systems into existing structures and architectures are analysed and expla
Multiaxial stress states are very common in engineering applications. To obtain a plane stress state in a material are used different experimental procedures. Biaxial tensile tests of cruciform specimens represent one...
Multiaxial stress states are very common in engineering applications. To obtain a plane stress state in a material are used different experimental procedures. Biaxial tensile tests of cruciform specimens represent one of the most versatile techniques with accurate results for a wide range of materials. Specimen geometry and size must be adapted to biaxial experiments that use devices attached to universal testing machine. Biaxial tensile tests are performed using cruciform specimens optimized by a numerical study through finite element analysis and a custom built attachable device developed. The results obtained show that the method proposed in this paper can be used with good results to characterize the behaviour of ductile materials.
In real life experience, machine and structure elements are subjected to complex loading history. Combined loading testes facilitate the understanding of materials behavior subjected to multiaxial stress state. In thi...
In real life experience, machine and structure elements are subjected to complex loading history. Combined loading testes facilitate the understanding of materials behavior subjected to multiaxial stress state. In this paper are presented experimental investigations used to evaluate the influence of an initial type of loading on material properties which will be subsequently tested through another load type. Initial tests are tension tests, by different elongations, and subsequent tests are torsion tests, until break. Circular cross section specimens will be used in these tests. Tension tests have been performed on a universal testing machine. Subsequently torsion tests have been conducted through an attachable device. It was found that the energy associated with plastic deformation obtained by subsequent torsional tests has the dominant influence on the material total plastic energy, although initial test was tension.
We propose a rehabilitation device that we intend to be low cost and easy to manufacture. The system will ensure functionality but also have a small dimensions and low mass, considering the physiological dimensions of...
We propose a rehabilitation device that we intend to be low cost and easy to manufacture. The system will ensure functionality but also have a small dimensions and low mass, considering the physiological dimensions of the foot and lower leg. To avoid injure of the ankle joint, this device is equipped with a compliant joint between the motor and mechanical transmission. The torque of this joint is intended to be adjustable, according to the degree of ankle joint damage. To choose the material and the dimensions of this compliant joint, in this paper we perform the first stress simulation. The minimum torque is calculated, while the maximum torque is given by the preliminary chosen actuator.
As some studies show, the number of people over 65 years old increases constantly, leading to the need of solution to provide services regarding patient mobility. Diseases, accidents and neurologic problems affect hun...
As some studies show, the number of people over 65 years old increases constantly, leading to the need of solution to provide services regarding patient mobility. Diseases, accidents and neurologic problems affect hundreds of people every day, causing pain and lost of motor functions. The ability of using the upper limb is indispensable for a human being in everyday activities, making easy tasks like drinking a glass of water a real challenge. We can agree that physiotherapy promotes recovery, but not at an optimal level, due to limited financial and human resources. Hence, the need of robot-assisted rehabilitation emerges. A robot for upper-limb exercises should have a design that can accurately control interaction forces and progressively adapt assistance to the patients' abilities and also to record the patient's motion and evolution. In this paper a short overview of upper limb rehabilitation devices is presented. Our goal is to find the shortcomings of the current developed devices in terms of utility, ease of use and costs, for future development of a mechatronic system for upper limb rehabilitation.
In the department of computer science and electrical engineering (CSEE), Kumamoto university, a series of student experiments are prepared for 2nd and 3rd graders. In the technical educations, experiments about the co...
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In the department of computer science and electrical engineering (CSEE), Kumamoto university, a series of student experiments are prepared for 2nd and 3rd graders. In the technical educations, experiments about the computer science and electrical engineering are important to study the engineering comprehensively. In experiment I, 2nd graders study the fundamental treatment of measurement equipments, behaviors of major devices and technical writing of engineering reports. In experiment II, 3rd graders study technical issues about computer science and electrical engineering in more detail. This paper concerns the experimental program entitled “measurement and control using embedded system” in experiment II for 3rd graders. The purpose of this experiment is to design a simple PID controller on the micro control units (Lenesas M16C/26 MCU). To implement the PID controller, students program the software functions step by step, e.g. PWM signal generation using interrupted handling, encoder counter using the event timer. The detail of experimental program using embedded system is explained in this paper.
Ankle injuries are amongst the most common injuries of the lower limb. Besides initial treatment, rehabilitation of the patients plays a crucial role for future activities and proper functionality of the foot. Traditi...
Ankle injuries are amongst the most common injuries of the lower limb. Besides initial treatment, rehabilitation of the patients plays a crucial role for future activities and proper functionality of the foot. Traditionally, ankle injuries are rehabilitated via physiotherapy, using simple equipment like elastic bands and rollers, requiring intensive efforts of therapists and patients. Thus, the need of robotic devices emerges. In this paper, the design concept and some modelling and simulation aspects of a novel ankle rehabilitation device are presented.
In the last decades, mechanical engineering applications have extensive use in many subdomains. Many researchers have used Al2O3 40TiO2 (AMDRY6250) type coatings that have a wide use of plasma jets, significantly impr...
In the last decades, mechanical engineering applications have extensive use in many subdomains. Many researchers have used Al2O3 40TiO2 (AMDRY6250) type coatings that have a wide use of plasma jets, significantly improving their wear, corrosion resistance and heat shock properties. It is especially used for hydraulic components such as pumps, impellers, and blowers. The performance of Al2O3 40TiO2 layer is conditioned by a number of technological parameters of deposition, powder granulation and deposition incidence angle. In the present study, the authors will make sequential depositions of Al2O3 40TiO2 on the surface of a material coming from a hydraulic system. Microstructural analysis of optical microscopy, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDAX) are performed both in the surface of the deposited material and in the section of the coated specimens, identifying the microstructure and the component phases. The authors highlighted the emergence of the 'splat' type of formations that are specific to the ceramic coatings in the deposited layers and a good adhesion to the base material authorizing the use of this powder in the reconditioning of the hydraulic systems.
The authors theoretically investigated and then validated the power loss generated both by sliding and rolling in a modified thrust ball bearing with 3 balls operating at low axial load and grease lubrication. Based o...
The authors theoretically investigated and then validated the power loss generated both by sliding and rolling in a modified thrust ball bearing with 3 balls operating at low axial load and grease lubrication. Based on ball forces and moment equilibrium, it has been determined the tangential forces on contact ellipses. The hydrodynamic rolling friction forces have been determined by using Biboulet & Houpert's methodology considering base oil viscosity of the grease. Total power loss has been obtained as a sum of two components: power loss generated by sliding and power loss generated by rolling. Also, total friction torque has been theoretically determined and, as an alternative method, the total power loss has been calculated as a product between total friction torque and angular speed. Finally, based on previously experimental results, the power loss has been validated as the product between experimentally total friction torque and angular speed. A good correlation between the power losses determined by all three methods for 100, 200, 300 and 400 rpm have been obtained.
The name of amorphous metals is assigned to metals that have a non-crystalline structure, but they are also very similar to glass if we look into their properties. A very distinguished feature is the fact that amorpho...
The name of amorphous metals is assigned to metals that have a non-crystalline structure, but they are also very similar to glass if we look into their properties. A very distinguished feature is the fact that amorphous metals, also known as metallic glasses, show a good electrical conductivity. The extension of the limit state criteria for different materials makes this type of alloy a choice to validate the new criterions. Using a new criterion developed for biaxial and triaxial state of stress, the results are investigated in order to determine the applicability of the mathematical model for these amorphous metals. Especially for brittle materials, it is extremely important to find suitable fracture criterion. Mohr-Coulomb criterion, which is permitting a linear failure envelope, is often used for very brittle materials. But for metallic glasses this criterion is not consistent with the experimental determinations. For metallic glasses, and other high-strength materials, Rui Tao Qu and Zhe Feng Zhang proposed a failure envelope modeling with an ellipse in σ-τ coordinates. In this paper this model is being developed for principal stresses space. It is also proposed a method for transforming σ-τ coordinates in principal stresses coordinates and the theoretical results are consistent with the experimental ones.
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