scholarly journals A Tetra-State Hopping Robot Driven by Shape Memory Alloy Spring

2011 ◽  
Vol 2-3 ◽  
pp. 402-407 ◽  
Author(s):  
Tian Qi Liu ◽  
Shu Ping Chen ◽  
Jiang Long Guo ◽  
Zhi Long Dou ◽  
Chun Liu ◽  
...  

According to the characteristics of jumping locomotion, a solution of Tetra-state Hopping Robot (for short: THR) actuated by Shape Memory Alloy Spring (for short: SMAS) is presented in this paper. This article establishes a mechanical model of the jumping robot and analyzes the kinematics and the dynamics of the mechanical model. Lagrange method is applied to analyze the dynamics the mechanical model. Meanwhile, a preliminary explanation of the THR flipping phenomenon during the take-off and flight process is conducted from the perspective of momentum moment.

2014 ◽  
Vol 26 (6) ◽  
pp. 652-662
Author(s):  
Fabrizio Niccoli ◽  
Carmine Maletta ◽  
Emanuele Sgambitterra ◽  
Franco Furgiuele

Actuators ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 8
Author(s):  
Xiangsen Kong ◽  
Yilei Gu ◽  
Jiajun Wu ◽  
Yang Yang ◽  
Xing Shen

In order to alleviate the problems of complex structure and low reliability of traditional Shape Memory Alloy (SMA) rotary actuator, a planar vortex actuator (PVA) based on SMA material was proposed to directly output torque and angular displacement. Based on the calculation method of PVA and the constitutive model of the phase transition equation of SMA, the mechanical model is established, and the pre-tightening torque, temperature, output torque, and rotation angle are obtained. The relationship expression between the tests has verified the mechanical model. The results show that the relationship between the excitation temperature and the output torque, the coefficient of determination between the calculated value and the tested value, is 0.938, the minimum error is 0.46%, and the maximum error is 49.8%. In the relationship between angular displacement and torque, the coefficient of determination between the calculated value and the test value is 0.939, the maximum error is 58.5%, and the minimum error is 28.0%. The test results show that the calculated values of mechanical model and experimental data have similar representation form.


2018 ◽  
Vol 83 (3) ◽  
pp. 30905 ◽  
Author(s):  
S. Dufour ◽  
G. Vinsard

The shape memory alloy heating by eddy currents is a quick solution for the shape change. Then, the analysis of the temperature field as a function of the shape is important to build a mechanical model in large deformation. Even if the temperature can be obtained by experiment, a computational model is useful. The computation of the induced currents in a nickel–titanium shape memory alloy beam is here considered with a T − Ω model adapted to thin shells with the help of a change of coordinates. It allows us to take into account the shape change, without the need of remeshing, as a function of the temperature. Experiments are carried out to validate the model.


2016 ◽  
Vol 725 ◽  
pp. 405-409 ◽  
Author(s):  
Liang Tao ◽  
Chang Luo ◽  
Wei Xuan Li ◽  
Yao Jiang Zhang

NiTi shape memory alloy (SMA) vascular stent, with good bio-compatibility and super-elastic properties, has become an important medical device in clinical treatment of cardiovascular or cerebrovascular diseases. The free expansion of stent in vessel involves the mechanical behavior of geometric large deformation related to the structure of super-elastic. In this paper, the nonlinear mechanical model for the substructure of NiTi shape memory alloy vascular stent is established, and the displacement deformation equation is derived. The geometric non-linearity of the structure is proved. Furthermore, the geometric nonlinear mechanical model is verified by numerical method. The mechanical analysis model of NiTi shape memory alloy vascular stent is widely used in the field of tracheal stent and so on.


2010 ◽  
Vol 44-47 ◽  
pp. 2543-2547
Author(s):  
Yu Kui Wang ◽  
Cheng Guo ◽  
Jian Li ◽  
Zhen Long Wang

This paper discusses a design of a flexible bending biomimetic octopus arm unit. Firstly, bending function of the octopus arm is analyzed. Secondly, the structure of the arm unit driven by shape memory alloy (SMA) is presented which can realize flexible bending. Meanwhile, mechanical model of the arm unit is established to find the proper parameters of the arm unit. Finally, experiments are carried out to demonstrate the feasibility of the structure.


Sign in / Sign up

Export Citation Format

Share Document