Search results

This study aims to prevent occupational accidents occurring in the manufacturing industry by means of touch sensors. When the occupational accidents occurring in the manufacturing industry around the world are examined, it is seen that approximately 88% of occupational accidents occur from “dangerous movement” and 10% from “dangerous situation.” Although some studies related to safety culture studies, safety studies in design and collective or personal protective measures have been started, they have not been brought to an adequate level. It is observed that studies on dangerous movements continue even in many developed countries. In this study, first of all, a literature study was conducted. Occupational accidents experienced in the manufacturing sector in Turkey have been examined. In line with these investigations, a prototype circuit protection system has been developed that can prevent accidents caused by dangerous movement. With the circuit, its applicability and effectiveness were measured by conducting experiments on different manufacturing machines. The prototype circuit applied in this paper was made based on the logic of protective measures made on sawstop machines used in different sectors. In the experimental study conducted, it was observed that in 30 experiments conducted with a prototype on ten separate manufacturing machines, it stopped the machines 26 times at minimum and 29 times at maximum. On average, when looking at the system efficiency values, it was seen that the system was 81.6% effective, and it was observed that positive results could be obtained when converted into a real product.

In this study, their contribution to the prevention of work accidents caused by presses and rotary accents from machines used in the manufacturing industry by means of touch sensors used in Industry 4.0 was examined.

With Industry 4.0, different automation systems began to be switched in many areas and sectors. Studies have started on different sensors used also in Industry 4.0 in occupational health and safety studies, but it is seen that they have not been applied at an adequate level. It should be designed in such a way as to prevent errors or stop these errors in the studies performed. Today, sensors are produced at much lower costs than before. In addition, the constantly developing technology provides great convenience for these applications.

This study was applied for press and cylinder machines from manufacturing machines. This study has been tried for machines producing a maximum pressure of 300 tons.

A prototype was designed. Trials were done on some machines by prototype. There could be improve and find different solutions for safety problems in the industry with this perspective.

Traction applications, e.g. the IMs are mainly operated by field-oriented control (FOC). This control technique requires an accurate knowledge of the machine’s parameters, such as the main inductance, the leakage inductances and the stator and rotor resistance. The accuracy of the parameters influences the precision of the calculated rotor flux and the rotor flux angle and the decoupling of the machine’s equations into the direct and quadrature coordinate system (dq-components). Furthermore, the parameters are used to configure the controllers of the FOC system and therefore influence the dynamic behavior and stability of the control.

In this paper, three different methods to calculate the machine’s parameters, in an automated and rapid procedure with minimal measuring expenditure, are analyzed and compared. Moreover, a method to configure a control that reduces the overall Ohmic losses of the machine in every torque speed operation point is presented. The machine control is configured only with the identified machine parameter.

Simulations and test bench measurements show that the evolutionary strategy is able to identify the electrical parameters of the machine in less time and with low error. Moreover, the controller is able to control the torque of the machine with a deviation of less than 2 per cent.

The most significant contribution of the research is the potential to identify the machine parameter of an induction motor and to configure an accurate control with these parameters.

In this paper, the partitioned stator flux reversal permanent magnet (PM) (PS-FRPM) machines with Halbach array PMs are investigated to compare with the machine having the conventional parallel magnetized PMs, and conventional FRPM machine. This paper aims to discuss these issues.

The Halbach array PM machines with 2-, 3-, and 4-segment and ideal Halbach array PMs have similar topology and designed based on the PS-FRPM with parallel magnetized PMs. The open circuit analysis and electromagnetic performance has been calculated and compares with the aid of finite element (FE) method, and validated by experiments.

The PS-FRPMs with Halbach array PMs have higher back-EMF and torque performance, as well as lower cogging torque and torque ripple, all having significantly higher torque density than the FRPM machine with single stator. The experimental results and FE predicted results of the 2-segment Halbach PM prototype machine are compared and good agreement is achieved.

This paper introduces the new concept and design of PS-FRPMs having Halbach array PMs with different PM segments and idea PM array. The comparison with conventional FRPM and PS-FRPM with parallel magnetized PMs shows the benefits with PS-FRPMs with Halbach array PMs.

This paper aims to develop an electrochemical abrasive jet machining (ECAJM) technology to investigate the surface machining effect of Ti-6Al-4V alloy.

First, the ECAJM equipment was set up, and a series of experiments for the surface machining of Ti-6Al-4V alloy was performed.

The experimental results show that the flowing abrasives of 0.05 Wt.% can effectively remove the TiO₂ oxide film of Ti-6Al-4V alloy surface. In addition, the flowing abrasives produce cutting machining effect on the surface of titanium aluminum alloy, and the oxide film can be removed effectively. For the case of machining pressure of 0.4 Mpa and machining gap of 0.4 mm, the processing efficiency can be achieved up to 20 µm/s.

Under different machining pressure, the flowing abrasive with high kinetic energy impacting the Ti-6Al-4V alloy surface and the oxide film produced from the electrolytic reaction process can be removed effectively, thereby enhancing the efficiency of electrochemical machining process.

Rapid prototyping (RP) techniques are being increasingly used to manufacture injection molding and die casting core and cavity sets, known as tools, and for other tooling‐related parts, such as EDM electrodes. This paper presents a STL‐based finish machining technique for tools and parts made using RP techniques in order to achieve the tight tolerance and surface finish requirements necessary for tooling applications. Rotate, scale, translate and offset algorithms are used to pre‐process the 3D model prior to its manufacture. A machining strategy of adaptive raster milling of the surface, plus hole drilling and sharp edge contour machining, is developed to finish the parts and tools after fabrication using RP. Finally, a benchmark part was designed and fabricated using the above‐mentioned strategies and the results show the effectiveness of the developed software.

Presents an assignment model formulation for the machine cell formation problem in cellular manufacturing based on an appropriate definition of dissimilarlity between any pair of machines for the grouping problem. This dissimilarity measure considers the production volume or demand for the parts on the respective machines and forms the cost parameters for the assignment model which is to be minimized. Identification of the machine cells automatically yields the corresponding part groups which are then assigned to the cells. The model is fast‐converging, taking advantage of the well‐proven assignment algorithm. Also presents an algorithm for dealing with mild cases of exceptional elements and too many machine cells. Uses numerical examples to illustrate the model.

Presents the findings of a comprehensive survey conducted among a wide variety of US machine shops. The objectives of the study were to develop the literature‐based just‐in‐time (JIT) machine shop model and to study empirically the changes taking place in the operation of machine shops in response to increasing demands by customers for JIT deliveries of products. Determines basic facility operating characteristics, machine operator characteristics, shopfloor control policies, and overall shop performance characteristics of machine shops having a significant level of sales to JIT customers. Discusses these findings with respect to the JIT machine shop model described in the previous literature. Supplies descriptive information for machine shops having little or no sales to JIT customers, to identify operating differences between the two classes of machine shops.

IN order to obtain machines of large carrying capacity, there is a tendency to increase the number of power units, and it is of great interest to consider the effect of this policy upon safety in flight. It is obvious that, if all the power units are of the same construction, the possibility of failure of one engine in a machine fitted with two engines is twice that in a machine fitted with one engine, so that in general the probability of one unit going out of action in a multi‐engined machine is proportional to the number of power units employed. In the case of a single‐engined machine horizontal flight cannot be maintained after the engine fails, and unless the failure occurs in the vicinity of a safe landing ground disaster may result. In the case of a multi‐engined machine, however, if level flight can be maintained on the power obtainable from the remaining units, it may bo possible to arrive at a safe landing ground without further trouble. The question, therefore, arises as to which factor is the more important, the increase in the probability of failure, or the ability to fly level with an engine out of action.

The paper develops an algorithm for eliminating bottleneck parts in a cellular manufacturing setting. Bottlenecks are eliminated by determining the machine duplication pattern that minimizes total duplication costs. A unique feature of the algorithm is that it recognizes that under some conditions machine duplication costs can be minimized by increasing the number of machine cells. Examples of such situations are given.

Procedures to reduce set‐up times at individual machines have been well documented; however, very little research has been conducted on developing an effective strategy to prioritize set‐up reduction procedures in a multi‐machine facility. Describes a new and innovative way – a throughput approach – to prioritize set‐up reduction procedures in a multi‐machine production system.