Magnetostrictive actuator

BE-1372 Magnetostrictive actuators for damage analysis and vibration control Pr. U. Lacce UnN. Napoli... 

One of the main drawbacks of the magnetostrictive actuators is their fliermal drift. For the bulk Terfenol-D actuators, it has been known that the thermal expansion (10 K ) develops strains comparable to the magnetostrictive ones for AT=150K. For a simple... 

Eda, H. et al.. Study on giant magnetostriction actuator—Development of device with high power and ultra precision positioning. Bull JSPE (in Japanese), 57,3 (1991) 532. 

Fig. 6.28. View of the piezo actuator and its payload equipped with a position sensor and an accelerometer - the piezo actuator right) is excited with a magnetostrictive actuator (left)...

Although there is no large-volume application for magnetostrictive actuators at the moment, some are already used for specific applications in domains such as pumps, micropositioners, and transducers, and research into... 

Fig. 6.36. Reluctance description of the magnetic circuit of a magnetostrictive actuator with N coil turns and a magnetostrictive rod reluctance Rr...

T. Fukuda [65] has opened the field of miniature magnetostrictive actuators and motors taking advantage of wireless magnetic excitation. He has experimented with two small self-moving hnear motors (some of cubic centimeter dimensions) based on a conversion-mode principle. 

The following sections focus on the self-sensing effect in piezoelectric and magnetostrictive actuators. Therefore, the most important and basic principles of this group of solid-state actuators will be given below from the standpoint of system theory. 

Piezoelectric and magnetostrictive actuators in particular, as well as actuators with electrically controllable fluids, are coimted among the unconventional actuators. Actuators with shape memory alloys and polymers as well as other, less common actuators sometimes require very simple and sometimes fairly complex amplifiers, which have to be timed to the actuator and the signals that are to be processed. However, we will not go into the details of such special cases. 

Solid-state actuators and actuators with controllable fluids show certain similarities piezo actuators and electrorheological fluids are driven with electrical fields whereas magnetostrictive actuators and magnetorheological fluids draw their actuation energy from a magnetic field. We will therefore consider the power electronics of these two superordinate groups, but still we will mention the differences between the two different actuator types of each group. 

Power Electronics for Magnetostrictive Actuators and Actuators with Magnetorheological Fluids... 

Engdahl, G. Loss simulations in magnetostriction actuators. J. Appl. Phys. 79 (8) (1996)... 

Claeyssen, F. State of the art in the field of magnetostrictive actuators. Proc. Actuator 94 Conf., Axon, Bremen, Gemany (1994), pp. 203-209... 

ETREMA Terfenol-D Magnetostrictive Actuators Information. Etrema Products, USA (1993), p. 6... 

Honda, T. Fabrication of Magnetostrictive Actuators Using Rare-Earth (Tb, Sm)-Fe Thin Films. J. Appl. Phys. 76 (10), 15 Nov 1994, pp. 6994-6999... 

FoUinger, O. Regelungstechnik. Oldenbourg-Verlag, Miinchen, Wien (1990) Kuhnen, K. Janocha, H. Schommer, M. Exploitation of inherent sensor effects in magnetostrictive actuators. Proc. 9th Int. Conf. on New Actuators, Bremen (2004), pp. 367-370... 

Pratt, J. Flatau, A.B. Developement and analysis of a self-sensing magnetostrictive actuator design. Proc. SPIE Smart Structures and Mater. 1917, Albuquerque (1993) pp. 952-961... 

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