Prestrainend shape memory alloys (SMA) change their length when heated above their transformation temperature. Based on this property this paper presents the design of macroscopic SMA actuators scalable in force and length that keeps up a short cool down time to guarantee a high frequency of contraction/stress cycles and the possibility of arranging the fixings in any direction. A new model of ...

One of the research goals in robotics is the development of home-help robots. The development of a control approach for a novel lightweight and multifunctional shape memory alloy (SMA) actuator scalable in force and length for robots is presented in this paper. The SMA actuator is based on lightweight bundles of thin wires of prestrainend shape memory alloy that change their length when heated ...

As a rst step towards the design of a high frequency, high force, large strain shape memory alloy(SMA) actuator, we model in this work a thermoelectrically cooled thin SMA layer linear actuator. The SMA is subjected to cyclic phase transition between the martensitic and austenitic phases by alternate heating/cooling, achieved with the thermoelectric Peltier e ect of a pair of P/N semiconductors...

In this paper, a modular microactuator based on shape memory alloy (SMA) actuation to drive the joints of a microgripper is described. Its design is a combination of two SMA actuators installed on the links of a special mechanism : one of them drives the rotation of the joint and the other one produces the necessary force to manipulate objects. An accurate model of the thermo-mechanical behavio...

Shape Memory Alloys (SMA's) are generally considered to be a slow and imprecise means of actuation. With the SMA actuator designed at McGill University we wish to show the contrary. In this paper, several SMA actuators are used to actively damp an external impulse disturbance on a mass to be isolated from vibrations. The vibration isolation testbed consists of a `strong' actuator to low-pass th...

− A new type of actuator is presented where Shape Memory Alloy (SMA) wires are embedded within artificial “blood vessels.” Fluid flowing through vessels allows the SMA wires to be rapidly cooled by convection, resulting in greater bandwidth than ordinarily possible. Combinations of electric, fluidic, and thermal inputs can be used to control the contraction/extension of the SMA wires within the...

In this paper, the design and control of a novel shape memory alloy (SMA) actuator that possesses impressive payload lifting capabilities are presented. The actuator consists of 48 nickel-titanium SMA wires mechanically bundled in parallel forming one powerful artificial muscle. This new linear actuator can apply up to 100 lbf (445 N), which is approximately 300 times its weight, over a maximum...

A simulator is developed to model and design high strain shape memory alloy (SMA) tension actuators. The simulator may be used predict characteristics of a given actuator, or to design its geometry under speci cations such as force, speed, stroke and size. The accuracy of the model is veri ed experimentally in reference to an existing NiTi shape memory alloy prototype actuator. Having developed...

In recent years, the Preisach hysteresis model has emerged as the model of choice for the behaviour of many smart materials, such as shape memory alloys (SMA). This research treats the identi cation of Preisach models for a di erential SMA actuator. The traditional identi cation technique is applied, and several models are derived for the actuator. It is seen that the classical Preisach model i...

This present paper will study the requirements for development of a new Automatic Rotor Blades Folding (ARBF) system that could possibly solve the availability, compatibility and complexity issue of upgrading a manual to a fully automatic rotor blades folding system of a helicopter. As a subject matter, the Royal Malaysian Navy Super Lynx Mk 100 was chosen as the baseline model. The aim of the ...