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 ...

A recently developed constitutive model and a finite element formulation for predicting the thermomechanical response of SMA hybrid composite (SMAHC) structures is briefly described. Attention is focused on constrained recovery behavior in this study, but the constitutive formulation is also capable of modeling restrained or free recovery. Numerical results are shown for glass/epoxy panel speci...

Experimental results are presented to show that SMA actuators are able to control forces both rapidly and precisely. An antagonistic pair of constrained actuators is shown to be capable of rapidly changing the setpoint throughout a 7.00 N range. Although the system entered into a limit cycle at the setpoint, the limit cycle magnitude was small. The peak to peak amplitude of the limit cycles was...

This paper presents a nonlinear control scheme for position control of a flexible beam system using Shape Memory Alloy (SMA) actuators. Due to their interesting properties such as force generation capacity, possibility of miniaturization, and power consumption, these devices have been gaining increased popularity in the past few years. However, SMA actuators possess undesirable characteristics ...

In some systems with hysteresis behavior like Shape Memory Alloy (SMA) actuators and Piezo actuators, we essentially need an accurate modeling of hysteresis either for controller design or performance evaluation. One of the most interesting Hysteresis non-linearity identification methods is Preisach model in which hysteresis is modeled by linear combination of elemental operators. Despite good ...

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...

Position control of Shape Memory Alloy (SMA) actuators has been a challenging topic during the last years due to their nonlinearities in the governing physical equations as well as their hysteresis behaviors. Using the inverse of phenomenological hysteresis model in order to compensate the input–output hysteresis behavior of these actuators shows the effectiveness of this approach. In this pape...

In this paper, two diierent control technics for SMA actuators are presented depending on the nature of the robotic application. The rst one based on a position feedback loop permits to control accurately the phalanx joint position for manipulation application. The second one is based on a temperature feedback loop to remotly steer an endoscope by a joystick. Their simplicity permits to integra...

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...

A common problem with space suit systems is overly rigid gloves that resist astronaut finger motion and gripping. In this paper, the design of a mechanism is considered that exploits the small-scale nature of shape memory alloys for actuating glove fingers to assist hand gripping. The design problem is introduced by considering the objectives, constraints, and variables relevant to a spacesuit ...