Improving the Force and Time Response of a DC Solenoid Electromagnetic Actuator by Changing the Lower Core Angle

Eduard Plavec,Miroslav Petrini?,Mladen Vidovi? 한국전자파학회JEES 2021 Journal of Electromagnetic Engineering and Science Vol.21 No.2

The aim of almost any electromagnetic actuator development is to increase the electromagnetic force with which an actuator acts on a plunger with as fast a time response as possible while maintaining the dimensions as small as possible. This paper presents research on the impact of the lower core angle on the force and time response of a DC solenoid electromagnetic actuator. The research method is based on the analytical analysis of the magnetic path of the DC solenoid electromagnetic actuator and a comparison with the numerical simulation results. A transient numerical simulation was performed on a 2D axial-symmetric model of the electromagnetic actuator and included simultaneously solving time-dependent partial differential equations of the electromagnetic actuator’s magnetic, electrical, and mechanical subsystems. The magnetic subsystem was analyzed by the finite element method (FEM) using the ANSYS Electronics software package. The three prototype models with different lower core angles were produced and tested in the accredited Laboratory Center of KONČAR Electrical Engineering Institute. The obtained measurements are compared with the analytical results and numerical simulation results.

Design of Compact Electromagnetic Actuator with Permanent Magnet for High Efficiency

이보하(BoHa Lee),이종원(Chong-Won Lee) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

As a dynamic actuator for attenuating the engine-induced vibration transmitted to passenger vehicle chassis or investigating the vibration transfer path of the vehicle. an electromagnetic actuator. consisted of a runner, two stators and pairs of electromagnets and permanent magnets, is developed. It features that it is compact to be fit into the limited space and yet, it possesses high efficiency and wide frequency bandwidth for effective control of engine vibrations in standard size passenger cars. By using the permanent magnets in electromagnetic system, we can increase the actuating force of the electromagnetic system and decrease the total amount of the power consumption of actuator when it operates. In addition an electronic circuit device is developed such that the displacement between the electromagnet pair and the target can be estimated from measurement of flux density of the installed permanent magnet only. It is found that the resolution and frequency bandwidth of the displacement estimator are about 3㎛ and 0 to 4㎑, respectively. The designed electromagnetic actuator is capable of attenuating the vibration over the frequency range of 100 to 400㎐. which is satisfactory for applications of interest.

Updated MinimumWeighted Norm Based Electromagnetic Field Control for a Magnetically Actuated Microrobot

Jayoung Kim,Seonghwan Jeong,Jong-Oh Park,Han-Sol Lee,Cheong Lee,Chang-Sei Kim 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.3

Herein, we present a novel electromagnetic field control methodology against a heating problem that can perform both desired actuation and lower heating of an electromagnet actuator comprising several electromagnets for magnetically actuated microrobot. The proposed method can balance the heating temperature of each electromagnet in a multiple coiled electromagnetic actuator which should be sustained in a similar state to prevent overheating while maintaining a desired magnetic force. Based on the conventional magnetic field model, the controller employs a real-time updated minimum weighted norm of induced currents by considering the physically limited current source and temperature feedback of each coil. The simulation results indicate that the heating temperature is lower than the conventional method during the same operation time. The performance of capsule motion and respective heating temperature through the proposed method was validated in ex-vivo experiments in a pig intestine for the actual clinical application. During the whole motion cycle of a wireless magnetic capsule in the intestine sample, the measured heating temperature could be significantly reduced. Hence, the temperatures of all the electromagnets were balanced at a similar level without any extremely high temperatures for specific electromagnets. Eventually, the proposed control method can extend the operating time of the conventional electromagnetic actuator and enhance the capability of real application.

소형 및 저비용화를 위한 전자석-스프링 구동장치 연구

김세웅,이창섭,최현영 한국군사과학기술학회 2019 한국군사과학기술학회지 Vol.22 No.3

This paper provides a fin actuation system of missile based on electromagnetic-spring mechanism to miniaturize the system and lower the cost. Compared with proportional electro-mechanical actuators, the output of Electromagnetic-Spring Actuators(EMSA) has two or three discrete states, but the mechanical configuration of EMSA is simple since it does not need power trains like gears. The simple mechanism of EMSA makes it easy to build small size, low cost, and relatively high torque actuators. However, fast response time is required to improve the dynamic performance and accuracy of missiles since bang-off-bang operation of EMSA affects the flight performance of missile. In this paper the development of EMSA including parameter optimization and mathematical modeling is described. The simulation results using Simulink and experimental test results of prototype EMSAs are presented.

소형 2 자유도 전자기 구동기 모듈 개발

김영식(Youngshik Kim),심현호(Hyun-Ho Shim),이경민(Kyung-min Lee),신부현(Buhyun Shin) 제어로봇시스템학회 2017 제어·로봇·시스템학회 논문지 Vol.23 No.7

The proposed two degree-of-freedom electromagnetic oscillatory actuator has a novel structure to combine two electromagnetic actuators of the moving-coil type. In order to rotate the actuator, the coil is attached to the moving frame, acting as the moving-coil type. There is three magnets, in the middle and inside each moving frame. The direction of the magnetism is perpendicular to the coil in order to change the direction of current induced to the coil and oscillate the moving frame. There are two types of forces applied to the 2-DoF electromagnetic oscillatory actuator. The magnetic force between the magnets holds the moving frame on the left or right side. That magnetic force is called as a holding force. The electromagnetic force generates the oscillatory motion when the current is applied to the coil. The overall size is 15 mm (W) × 15 mm (D) × 50 mm (H). All frames are made of ABS plastic using a rapid prototyping process to reduce inertia. The magnet material is ND35. The dynamic modeling and electromagnetic simulations and experiments are conducted. Resonance frequency is 18.5 Hz with only moving parts and 15.5 Hz including middle magnet. The laser beam profile shows 2-D motion for swing motion for various applications.

Design of a Moving-magnet Electromagnetic Actuator for Fast Steering Mirror through Finite Element Simulation Method

Yongjun Long,Jinqiu Mo,Xiaohui Wei,Chunlei Wang,Shigang Wang 한국자기학회 2014 Journal of Magnetics Vol.19 No.3

This paper develops a moving-magnet electromagnetic actuator for fast steering mirror (FSM). The actuator achieves a reasonable compromise between voice coil actuator and piezoelectric actuator. The stroke of the actuator is between the strokes of a piezoelectric actuator and a voice coil actuator, and its force output is a linear function of air gap and excitation current within our FSM travel range. Additionally, the actuator is more reliable than voice coil actuator as the electrical connection in the actuator is static. Analytically modeling the actuator is difficult and time-consuming. Alternatively, numerous finite element simulations are carried out for the actuator analysis and design. According to the design results, a real prototype of the actuator is fabricated. An experimental test system is then built. Using the test system, the force output of the fabricated actuator is evaluated. The test results validate the actuator analysis and design.

Modeling and Analysis of a Novel Two-Axis Rotary Electromagnetic Actuator for Fast Steering Mirror

Yongjun Long,Chunlei Wang,Xin Dai,Xiaohui Wei,Shigang Wang 한국자기학회 2014 Journal of Magnetics Vol.19 No.2

This paper focuses on the modeling and analysis a novel two-axis rotary normal-stress electromagnetic actuator with compact structure for fast steering mirror (FSM). The actuator has high force density similar to a solenoid, but its torque output is nearly a linear function of both its driving current and rotation angle, showing that the actuator is ideal for FSM. In addition, the actuator is designed with a new cross topology armature and no additional axial force is generated when the actuator works. With flux leakage being involved in the actuator modeling properly, an accurate analytical model of the actuator, which shows the actuator’s linear characteristics, is obtained via the commonly used equivalent magnetic circuit method. Finally, numerical simulation is presented to validate the analytical actuator model. It is shown that the analytical results are in a good agreement with the simulation results.

A novel design of active accelerator pedal using linear electromagnetic actuator

Lee, Jae-Yong,Kim, Jin-Ho,Woo, Sang-Min,Lee, Jeh-Won 대한기계학회 2010 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.24 No.1

This paper describes a novel design of an active accelerator pedal(AAP) using a linear electromagnetic actuator that transfers warning messages recognized by the automobile from the sensors to the driver. In an emergency driving situation, the electromagnetic actuator creates additional pedal forces such as active pedal force and vibration force. In a passive situation however, the actuator does not produce additional force. In the past, a system with a rotary actuator was developed for AAP but was found to have critical drawbacks such as inaccurate movement by backlash and torque occurrence due to the high gear ratio. This research, therefore, aims to solve these drawbacks and maximize car safety by optimizing the electromagnetic linear actuator. Finite element analysis is performed to analyze the coupled system of electric, magnetic, and mechanical subsystems, and to characterize the dynamic performance of the proposed actuator system. A novel design of the AAP system with the optimized electromagnetic linear actuator is developed. The dynamic characteristics of the AAP system are simulated by a 3D dynamic analysis software program. Satisfactory results were obtained. Finally, the test result and the simulation result of the AAP system are compared.

Shape memory alloy–based biopsy device for active locomotive intestinal capsule endoscope

Le, Viet Ha,Hernando, Leon-Rodriguez,Lee, Cheong,Choi, Hyunchul,Jin, Zhen,Nguyen, Kim Tien,Go, Gwangjun,Ko, Seong-Young,Park, Jong-Oh,Park, Sukho SAGE Publications 2015 Proceedings of the Institution of Mechanical Engin Vol.229 No.3

<P>Recently, capsule endoscopes have been used for diagnosis in digestive organs. However, because a capsule endoscope does not have a locomotive function, its use has been limited to small tubular digestive organs, such as small intestine and esophagus. To address this problem, researchers have begun studying an active locomotive intestine capsule endoscope as a medical instrument for the whole gastrointestinal tract. We have developed a capsule endoscope with a small permanent magnet that is actuated by an electromagnetic actuation system, allowing active and flexible movement in the patient's gut environment. In addition, researchers have noted the need for a biopsy function in capsule endoscope for the definitive diagnosis of digestive diseases. Therefore, this paper proposes a novel robotic biopsy device for active locomotive intestine capsule endoscope. The proposed biopsy device has a sharp blade connected with a shape memory alloy actuator. The biopsy device measuring 12mm in diameter and 3mm in length was integrated into our capsule endoscope prototype, where the device's sharp blade was activated and exposed by the shape memory alloy actuator. Then the electromagnetic actuation system generated a specific motion of the capsule endoscope to extract the tissue sample from the intestines. The final biopsy sample tissue had a volume of about 6mm(3), which is a sufficient amount for a histological analysis. Consequently, we proposed the working principle of the biopsy device and conducted an in-vitro biopsy test to verify the feasibility of the biopsy device integrated into the capsule endoscope prototype using the electro-magnetic actuation system.</P>

Effect of Mechanical Damping and Electrical Conductivity on the Dynamic Performance of a Novel Electromagnetic Engine Valve Actuator

Sang-Shin Park,Jinho Kim,Young Choi,Jung-Hwan Chang 한국정밀공학회 2008 International Journal of Precision Engineering and Vol.9 No.3

We investigate the effect of mechanical damping and electrical conductivity on the dynamic performance of a new electromagnetic engine valve actuator that employs a permanent magnet. The key dynamic performance factors are the transition time and the landing velocity of the armature. Two-dimensional dynamic finite element analyses are performed to simulate a coupled system. The results show that mechanical damping and electrical conductivity have similar effects on the dynamic performance of the engine valve actuator. Subsequently, it is possible to replace the role of mechanical damping by controlling the electrical conductivity through the thickness and number of steel core laminations.