Application of smart material-hydraulic actuators

Abstract

The application of a new class of actuators is considered. The actuators under development combine a high energy density smart material, specifically a piezoelectric material, with internal servohydraulic components. Large displacement outputs are produced, while the high force capacity of the stiff smart material is retained, for a net highenergy output. The actuator is considered "power-by-wire" because only electrical power is provided from the vehicle or system controller. A primary motivating application is in unmanned combat air vehicles (UCAVs). The particular actuation needs of these vehicles, in flight control and other utility functions, are described and distilled to a set of relevant device requirements. Other potential applications, such as flight motion simulation, are also highlighted. The new actuation architecture offers specific advantages over centralized hydraulic systems and has capabilities not present in ekctromechanical actuators (EMAs). The main advantage over centralized hydraulic systems is the elimination of the need for hydraulic lines. Compared to motor-driven ball screw type EMAs, the new actuators offer higher frequency response, and a larger peak-to-average output. A laboratory test facility designed to represent the loading experienced by a UCAV control surface is described. Key steps necessary to flight qualify the actuator are introduced.

Design, analysis and simulation of magnetostrictive actuator and its application to high dynamic servo valve

“…are reported in Refs. [5,6]. Material selection for mechanical design of micro sensors and micro actuators are discussed in Ref.…”

Characteristic investigations on magnetic field and fluid field of a giant magnetostrictive material-based electro-hydrostatic actuator

“…[7][8][9][10] To realize these improvements, there is a need to develop new actuators to replace the function of the centralized hydraulic components; accordingly, smart material electro-hydrostatic actuators (SMEHAs) can be used to do this work. 5,7,11 Recently, substantial research has been completed on the development of electro-hydrostatic actuators (EHAs) driven by various smart materials as follows: 5,12 Konishi et al 13 in 1993 developed one of the first reported hybrid hydraulic actuators. The maximum output power of the piezoelectric stack-based actuator was 34 W at a working frequency of approximately 300 Hz and a static bias pressure of 3 MPa.…”

“…Various smart materials have been developed for potential use in aerospace, automotive, and robotic applications. [1][2][3]5,7,10,11,[26][27][28] However, piezo-stacks generate significant heat mainly due to the hysteresis losses that can deteriorate their performance and permanently damage the piezomaterial at high driving frequencies. In contrast, a giant magnetostrictive material (GMM) are more robust than piezo-stacks, especially at high temperatures, while offering approximately the same bandwidth and higher maximum induced strain compared with the piezoelectric stacks.…”

Design and testing of piezoelectric-hydraulic actuators

“…9 The primary advantage compared to traditional hydraulics is the power-by-wire aspect, i.e. the elimination of hydraulic distribution lines.…”

“…Electronic drive of the actuator is also a consideration, though it is discussed elsewhere. 9 Like many systems, the overall design is an integrated and iterative one, where individual components can be designed, but then require redesign to work well with other subsystems. Testing at the component, subsystem and system level aids in The remainder of the paper describes basic concepts in solid-fluid actuation, illustrating operation and highlighting limitations.…”