ANISMA: A Prototyping Toolkit to Explore Haptic Skin Deformation Applications Using Shape-Memory Alloys

We present ANISMA, a software and hardware toolkit to prototype on-skin haptic devices that generate skin deformation stimuli like pressure, stretch, and motion using shape-memory alloys (SMAs). Our toolkit embeds expert knowledge that makes SMA spring actuators more accessible to human–computer interaction (HCI) researchers. Using our software tool, users can design different actuator layouts, program their spatio-temporal actuation and preview the resulting deformation behavior to verify a design at an early stage. Our toolkit allows exporting the actuator layout and 3D printing it directly on skin adhesive. To test different actuation sequences on the skin, a user can connect the SMA actuators to our customized driver board and reprogram them using our visual programming interface. We report a technical analysis, verify the perceptibility of essential ANISMA skin deformation devices with 8 participants, and evaluate ANISMA regarding its usability and supported creativity with 12 HCI researchers in a creative design task.

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The Dynamic of an Autoparametrical System With Two Coupled Pendulums Connected by SMA Spring

Volume 2: Automotive Systems; Bioengineering and Biomedical Technology; Computational Mechanics; Controls; Dynamical Systems ◽

10.1115/esda2008-59202 ◽

2008 ◽

Author(s):

Danuta Sado ◽

Krzysztof Gajos

Keyword(s):

Shape Memory Alloys ◽

Shape Memory ◽

Equations Of Motion ◽

Type System ◽

The Body ◽

System Response ◽

Influence Of Temperature ◽

Influence Of Temperature On ◽

Resistive Forces ◽

Sma Spring

The nonlinear dynamics of a three degree of freedom autoparametric system with two pendulums connected by SMA (Shape Memory Alloys) spring in the neighborhood internal and external resonance is presented in this works. The system consists of the body of mass m1 which is hung on a spring and a damper, and two connected by SMA spring pendulums of the length 1 and masses m2 and m3 mounted to the body of mass m1. It is assumed, that the motion of the pendulums are damped by resistive forces. Shape memory alloys have ability to change their material properties, for example stiffness. The equations of motion have been solved numerically and there was studied the influence of temperature on the energy transfer between modes of vibrations. Solutions for the system response are presented for specific values of the parameters of system. It was shown that in this type system one mode of vibrations may excite or damp another mode, and that except different kinds of periodic vibrations there may also appear chaotic vibrations. It depends on various amplitudes of excitation, frequencies ratio and different system parameters. Also fundamental is the influence of temperature on response of the system. For the identification of the responses of the system various techniques, including chaos techniques such as bifurcation diagrams and time histories, power spectral densities (FFT), Poincare` maps and exponents of Lyapunov may be use.

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Random Vibration Studies of a SDOF System With Shape Memory Restoring Force

Volume 7B: 17th Biennial Conference on Mechanical Vibration and Noise ◽

10.1115/detc99/vib-8084 ◽

1999 ◽

Author(s):

Luis Duval ◽

Mohammad N. Noori ◽

Zhikun Hou ◽

Hamid Davoodi ◽

Stefan Seleecke

Keyword(s):

Shape Memory Alloys ◽

Shape Memory ◽

Random Vibration ◽

Strong Dependence ◽

Random Excitation ◽

Restoring Force ◽

Wide Range ◽

Force Element ◽

Sma Spring ◽

Energy Dissipation Devices

Abstract Intelligent and adaptive material systems and structures have become very important in engineering applications. The basic characteristic of these systems is the ability to adapt to the environmental conditions. One of the new class of materials with promising applications in structural and mechanical systems are Shape Memory Alloys (SMA). The mechanical behavior of shape memory alloys in particular shows a strong dependence on temperature. This property provides opportunities for the utilization of SMAs in actuators or energy dissipation devices. However, the behavior of systems containing shape memory components under random excitation has not yet been addressed in the literature. Such study is important to verify the feasibility of using SMAs in structural systems. In this work a non-deterministic study of the dynamic behavior of a single degree-of-freedom (SDOF) mechanical system, having a Nitinol spring as a restoring force element is presented. The SMA spring is characterized using a one-dimensional phenomenological constitutive model based on the classical Devonshire theory. Response statistics for zero mean random vibration of the SDOF under a wide range of temperature is obtained. Furthermore, nonzero mean analysis of these systems is carried out.

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