Papers by Keyword: Actuator

Abstract: Electromagnetic actuators are used in a variety of technical applications especially in the automotive industry. In-line process control methods are an essential component of the Lean and Six Sigma methodology to ensure process quality. However, the current state of the art in process and quality control is largely limited to end-of-line measurements of the force output. Analysing the magnetic stray field is a promising method that can be used to draw conclusions on the properties and defects of the flux-conducting magnetic materials. This phenomenon can potentially be used to identify defects in magnetic actuators thus allowing inline quality-monitoring. In order to realize this feature, patterns in the magnetic stray field of an actuator have to be identified and linked to a specific defect. The resulting challenge is the analysis of large datasets in order to characterize the stray field anomalies. This paper summarizes the results of a study on linear magnetic actuators trying to prove a relationship between parasitic magnetic stray field and the overall force output of an actuator by analysing the data with statistical methods. The findings of this study suggest that certain statistical methods, like regression, are not well suited to build a prediction model for defects in actuators using a similar approach of measuring stray field outside the actuator. This is mainly due to the fact that prerequisites for model building are difficult to full fill within the context of stray field analysis. Nevertheless, the findings also suggest that methods of exploratory data analysis can be used to derive quality relevant information from data of stray field measurements. The paper elaborates on the problem of defining a population, choosing variables for model building, as well as model error.

Abstract: Very generally material science could be divided into two groups: scientists who try to invent new materials or improve existing ones and those who work on finding the best applications for the modern materials. Among them there is group named “smart materials” or “active materials”, which have ability to change theirs properties according to the external stimulation. One of the relatively most recent smart material is magnetic shape memory alloy, MSMA in abbreviation. The authors of the article focus on testing samples of this material and try to adapt them to use in fluid devices. The paper mentions about some most interesting valves’ designs equipped with smart materials and summaries the previous MSMA research of the authors. It begins with literature overview of smart material applications in pneumatic or hydraulic valves. There is only one example of MSMA application in valve, therefore the overview concerns mainly the use of piezoelectric, thermal shape memory alloys and giant magnetostrictive materials. Next section describes general properties of the magnetic shape memory alloys and underlines the differences between more widely known Thermal Shape Memory Alloys and MSMA materials. One of the most important property is wide, nonsymmetrical hysteresis in static characteristics of the material, which can be seen as advantage or disadvantage, depending on the application. The material preserves its shape until perpendicular magnetic field or additional force appear. The authors mention about modeling MSMA hysteresis aspect. Three different hysteresis models were briefly described: Generalized Prandtl-Ischlinski, Preisach and Krasnosel'skii-Pokrovskii. The last section treats about the current MSMA based valve design concept. It assumes usage of two identical pieces of MSMA materials and energize them oppositely. There is flapper mounted between MSMA samples, which displacement depends on the MSMA elongations. This actuator type is called “push-push” type. Lack of the return spring result in remaining of the flapper in its final position after decreasing of the supply current. The advantage of the solution could be lowering energy consumption of the valve, when the valve setting changes relatively rare during its work. In the future, the presented hysteresis models could improve the work of such MSMA based valve.

Abstract: Shape Memory Alloy is a material used to designing actuators. These actuators have many advantages. They are light, strong and silent. They are building in laboratory and tested because beside advantages they have disadvantages too. SMA actuators have nonlinear characteristics with hysteresis loop.In the first part of the paper Shape Memory Alloys are shortly described. Next mathematical model was formulated. In the paper the Preisach model was developed. Discrete form of the model was considered and implemented. After parameter identification model was implemented in LabView. Tests of the model were conducted and results were worked. Obtained characteristics of the SMA actuator are shown in the paper. At the end of the paper the conclusions were formulated.

Abstract: The report provides designs of actuators from the shape memory material-nitinol. It is proposed to use rods, wire, sheets and tape as working elements of the actuators. Special attention is paid to the designs of composite multil-element actuators, working elements of which are connected in parallel or in series. The experimental technique and results of experiments on evaluation of stresses developed by such actuators are given. It is shown that using the composite actuators from thin working elements facilitates control over their heating and cooling.

Abstract: Our article deals with the possibility of using shape memory material (SMA − Shape Memory Alloy) to create an actuator of the mechanical element. The biggest advantage of the SMA actuators compared to those made of conventional materials is that they have the ability to generate relatively great force, are of low weight and small size.

Abstract: This paper deals with the possibility of controlled deformation of the actuator of a flexible system. In the solution, large deformations of the actuator have been assumed. The model was made of a material capable of large deformations caused by internal pressure. The internal pressure was let into the cavities located in the actuator. The solution was realized analytically and numerically. The results show the relevance of the stated proposal.

Abstract: This research stems from the problematic present in many places in the World and more specifically where the members of this work lives: Tamaulipas (in the North of Mexico), it is one of the most important agricultural area in the country, but a serious problem in the region are the high temperatures around 40-45 Celsius degrees and the long periods of drought due to lack of rain [1], which is why a low-cost irrigation system for domestic crops based on rainwater storage is proposed using Arduino Uno as a control device for the electronic driver´s with the LabView as monitoring platform

Abstract: The work presented a research method of using the external magnetic field to do a numerical simulation of micro bionic fish. The fishtail skeleton was made of alloy sheet and the fish tissue was stuck on the alloy sheet with giant magnetostrictive material (GMM). Then the mechanical model of bionic fish was established. By controlling the swaying of fishtail through external magnetic frequency adjustment, it is possible to make the fish move about just like a natural fish. The statistics show that the average driving force when the bionic fish is switched on largely depends on the material parameter, blood viscosity and external magnetic frequency. The average driving force will increase with the growing elasticity modulus (EM) of fishtail material and blood viscosity. The bionic fish can get a quite large driving force particularly when the external magnetic frequency is getting close to the natural frequency of the system. Thus, these findings can serve as a major train of thought and gist for the design and control of micro bionic fish in vessel.

Abstract: This contribution deals with the control of a robot arm using a data glove. To construct the data gloves were used bend sensors and sensor of acceleration. Robotic arm was built using the modular actuators Dynamixel. Control program for controlling a robot arm using a data glove was created in Matlab.

Abstract: In this paper Switched reluctance motors are proposed for high temperature automotive applications due to the absence of magnets in comparison to conventional DC or brushless DC motors. The improvement in converter efficiency by the use of a current source converter in the front end simplifies the current control strategy that is otherwise required to be implemented in each phase coil winding. The analysis of the converter will be supported with simulation and the results for converter efficiency will be calculated. The proposed strategy will be suitable for implementation using a microcontroller based control mechanism for position control in an automotive application such as throttle control.