A two-way architectural actuator using NiTi SE wire and SME spring

Nematollahi, Mohammadreza; Mehrabi, Reza; Callejas, Miguel A; Elahinia, Hedyeh; Elahinia, Mohammad

doi:10.1117/12.2299817

Cited by 12 publications

(7 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nitinol (NiTi), is a biocompatible, low stiffness, shape memory alloy, which benefits from interesting features such as superelasticity and shape memory. Nitinol has been already used in many industrial applications as well as biomedical applications [8][9][10][11][12][13][14]. In addition to the inherent low stiffness, NiTi superelastic behavior can be made to be very similar to bone tissue.…”

Section: Introductionmentioning

confidence: 99%

Design, Modeling, Additive Manufacturing, and Polishing of Stiffness-Modulated Porous Nitinol Bone Fixation Plates Followed by Thermomechanical and Composition Analysis

Jahadakbar

Nematollahi

Safaei

et al. 2020

Metals

Self Cite

View full text Add to dashboard Cite

The use of titanium bone fixation plates is considered the standard of care for skeletal reconstructive surgery. Highly stiff titanium bone fixation plates provide immobilization immediately after the surgery. However, after the bone healing stage, they may cause stress shielding and lead to bone resorption and failure of the surgery. Stiffness-modulated or stiffness-matched Nitinol bone fixation plates that are fabricated via additive manufacturing (AM) have been recently introduced by our group as a long-lasting solution for minimizing the stress shielding and the follow-on bone resorption. Up to this point, we have modeled the performance of Nitinol bone fixation plates in mandibular reconstruction surgery and investigated the possibility of fabricating these implants. In this study, for the first time the realistic design of stiffness-modulated Nitinol bone fixation plates is presented. Plates with different levels of stiffness were fabricated, mechanically tested, and used for verifying the design approach. Followed by the design verification, to achieve superelastic bone fixation plates we proposed the use of Ni-rich Nitinol powder for the AM process and updated the models based on that. Superelastic Nitinol bone fixation plates with the extreme level of porosity were fabricated, and a chemical polishing procedure used to remove the un-melted powder was developed using SEM analysis. Thermomechanical evaluation of the polished bone fixation plates verified the desired superelasticity based on finite element (FE) simulations, and the chemical analysis showed good agreement with the ASTM standard.

show abstract

Section: Introductionmentioning

confidence: 99%

Design, Modeling, Additive Manufacturing, and Polishing of Stiffness-Modulated Porous Nitinol Bone Fixation Plates Followed by Thermomechanical and Composition Analysis

Jahadakbar

Nematollahi

Safaei

et al. 2020

Metals

Self Cite

View full text Add to dashboard Cite

show abstract

“…The mentioned traits have been making them appealing to scientists from an eclectic realm including automotive, 3–9 robotics, 10–14 and medicine. 15–23 More specifically, SMAs are used in the development of mechanical couplings, 24 mechanical actuators, 25–29 grippers, 30–33 micro-pumps, 34 microvalves, 35 control 36–42 and vibration of structures, 43–46 sensors, 47 and the like.…”

Section: Introductionmentioning

confidence: 99%

Adaptive predictive control of a novel shape memory alloy rod actuator

Hoseini

MirMohammadSadeghi

Fathi

et al. 2020

Proceedings of the Institution of Mechanical Engineers, Part I:

View full text Add to dashboard Cite

Shape memory alloys are among the highly applicable smart materials that have recently appealed to scientists from various fields of study. In this article, a novel shape memory alloy actuator, in the form of a rod, is introduced, and an adaptive model predictive control system is designed for position control of the developed actuator. The need for such an advanced control system emanates from the fact that modeling and controlling of shape memory alloy actuators are thwarted by their hysteresis nonlinearity, dilatory response, and high dependence on environmental conditions. Real-time identification and dynamic parameter estimation of the model are addressed according to orthogonal Laguerre functions and recursive least square algorithm. In the end, the designed control system is implemented on the experimental setup of the fabricated shape memory alloy actuator. It is observed that the designed control system successfully tracks the variable step and sinusoidal control references with startling accuracy of ±1 μm.

show abstract

“…NiTi is a shape memory alloy (SMA) with unique properties, such as biocompatibility, wear, and corrosion resistance, low modulus of elasticity, and high actuation work output [1][2][3][4]. These characteristics make NiTi useful for functional and smart structures in primary areas of biomedical and aerospace applications.…”

Section: Introductionmentioning

confidence: 99%

Additively Manufactured NiTi and NiTiHf Alloys: Estimating Service Life in High-Temperature Oxidation

et al. 2020

Self Cite

View full text Add to dashboard Cite

In this study, the effect of the addition of Hf on the oxidation behavior of NiTi alloy, which was processed using additive manufacturing and casting, is studied. Thermogravimetric analyses (TGA) were performed at the temperature of 500, 800, and 900 °C to assess the isothermal and dynamic oxidation behavior of the Ni50.4Ti29.6Hf20 at.% alloys for 75 h in dry air. After oxidation, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy were used to analyze the oxide scale formed on the surface of the samples during the high-temperature oxidation. Two stages of oxidation were observed for the NiTiHf samples, an increasing oxidation rate during the early stage of oxidation followed by a lower oxidation rate after approximately 10 h. The isothermal oxidation curves were well matched with a logarithmic rate law in the initial stage and then by parabolic rate law for the next stage. The formation of multi-layered oxide was observed for NiTiHf, which consists of Ti oxide, Hf oxide, and NiTiO3. For the binary alloys, results show that by increasing the temperature, the oxidation rate increased significantly and fitted with parabolic rate law. Activation energy of 175.25 kJ/mol for additively manufactured (AM) NiTi and 60.634 kJ/mol for AM NiTiHf was obtained.

show abstract

A two-way architectural actuator using NiTi SE wire and SME spring

Cited by 12 publications

References 20 publications

Design, Modeling, Additive Manufacturing, and Polishing of Stiffness-Modulated Porous Nitinol Bone Fixation Plates Followed by Thermomechanical and Composition Analysis

Design, Modeling, Additive Manufacturing, and Polishing of Stiffness-Modulated Porous Nitinol Bone Fixation Plates Followed by Thermomechanical and Composition Analysis

Adaptive predictive control of a novel shape memory alloy rod actuator

Additively Manufactured NiTi and NiTiHf Alloys: Estimating Service Life in High-Temperature Oxidation

Contact Info

Product

Resources

About