• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.4 s.121
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• pp.356-362
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• 2007

Magnetostrictive materials have been used for linear actuators due to its large strain, large force output with moderate frequency band in the presence of magnetic field. However their performance analysis is difficult because of nonlinear material behaviors in terms of coupled strain-magnetic field dependence, nonlinear permeability, pre-stress dependence and hysteresis. This paper presents a finite element analysis technique for magnetostrictive linear actuator. To deal with coupled problems and nonlinear behaviors, a simple finite element approach is proposed, which is based on separate magnetic field calculation and displacement simulation. The finite element formulation and an in-house program development are illustrated, and a simulation model is made for a magnetostrictive linear actuator. The fabrication and performance test of the linear actuator are explained, and the performance comparison with simulation result is shown. Since this approach is simple, it can be applied for analyzing magnetostrictive underwater projectors and ultrasonic transducers.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.4
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• pp.308-316
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• 2003

Terfenol-D is one of magnetostrictive materials which have the property of converting the energy in magnetic fields into mechanical movement and vice versa. We designed and fabricated a linear magnetostrictive actuator using Terfenol-D. It has 25 mm diameter and 100 mm long. To grasp the characteristics of it, a series of tests were performed in the range of 50 Hz below. Induced-strain actuation displacements of the actuator measured by test and predicted by magnetic analysis agreed well. And blocked forces according to the input currents were estimated from the testing results. Modelling method representing the exerting force of a linear magnetostrictive actuator was confirmed through some testing results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.17-24
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• 2002

Terfenol-D is one of magnetostrictive materials which have the property of converting the energy in magnetic fields into mechanical movement and vice versa. We designed and fabricated a linear magnetostrictive actuator using Terfenol-D. It has 25mm diameter and 100mm long. To grasp the characteristics of it, n series of tests were performed in the range of 50Hz below. Induced-strain actuation displacements of the actuator measured by test and predicted by magnetic analysis agreed well. And blocked forces according to the input currents were estimated from the testing results. Modelling method representing the exerting force of a linear magnetostrictive actuator was confirmed through some testing results.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.5
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• pp.289-293
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• 2000

This paper presents a study on the linear compensation of nonlinear hysteric actuators using the highly magnetostrictive film pattern as a strain sensor. Elements had a hybrid structure, in which thin soft glass substrate with the highly magnetostrictive amorphous FeCoSiB film was bonded on the PZT piezoelectric substrate. The magnetostrictive film as a strain sensor detects the deflection of an actuator, and a voltage signal from the strain sensor related to the deflection of an actuator is used for the linear control of an actuator.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.310.2-310
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• 2002

Terfenol-D is one of magnetostrictive materials which have the property of converting the energy in magnetic fields into mechanical movement and vice versa. We designed and fabricated a linear magnetostrictive actuator using Terfenol-D. It has 25mm diameter and 100mm long. To grasp the characteristics of it, a series of tests were performed in the range of 50㎐ below. Induced-strain actuation displacements of the actuator measured by test and predicted by magnetic analysis agreed well. (omitted)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1841-1844
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• 2005

A linear motor makes a long stroke by accumulating short steps, which is based on the quasistatic deformation of a magnetostrictive material in a magnetic field. It's also called as inchworm effect. The application areas of linear motors are an adaptive and active optics, X-Y positioning, precision alignment, etc. It is found that control of the frequency and current inputs are all that is necessary to control the speed handling ability of the linear motor. In inchworm mode, linear speeds of up to $500{\mu}m/s$ are achieved resulting from the accumulation of $25{\mu}m$ steps at 1.4A.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.69-71
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• 1994

In fabricating linear actuator using the GMA(Giant Magnetostrictive Alloy : Terfenol-D). the clamping unit is needed to accumlate each displacement from the GMA rod. Two types of the clamping unit (one is using piezoelectric device and the other electromagnetic farce) were made and tested. From the result of the experiment, we conclude that the electromagnetic clamping unit has advantages over the piezoelectric clamping unit.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.433-438
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• 2003

In this paper we explore the effectiveness of a magnetostrictive actuator(MSA) as a structural control device. A series of numerical and experimental tests are carried out with a simple aluminum beam only supported at each end by the actuator. After the equation of motion of the controlled system is obtained by the finite element method, a model reduction is performed to reduce the numbers of degree of freedom. A linear quadratic feedback controller is realized on a real-time digital control system to damp the first four elastic modes of the beam. Through some tests, we confirmed the possibility of this actuator for controlling beam-like structures.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.2
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• pp.26-30
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• 2001

This paper deals with the feasibility assessment of hybrid linear motor that operates based on self-moving cell concept. The moving cell is composed of Magnetostrictive actuator and a ring structure, and a cell train is constructed by connecting two cells in series. Since this motor uses strong push force of Terfenol-D actuators and friction of the cells, it can essentially produce long stroke and large force. The overall performance of the motor was measured in terms of speed and force.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.419-421
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• 1994

A linear actuator using Terfenol-D rod which can accumulate displacement of the rod was fabricated. The diameter of used rod is 12[mm] and the length of it is 75[mm]. It adopts the electromagnetic units as the clamping units. Basic characteristics of the linear actuator such as displacement vs. current, velocity vs. frequency, step size vs. frequency were experimented. When the driving current is 1[A] and 100[Hz], the velocity of the actuator is about 3.5[mm/s]. We discussed the cause of step size's decrease as increasing driving frequency and the solution to the problem.