Design and modelling of a reversible shape memory alloy torsion hinge actuator

Conventional hinge actuators often face limitations including excessive weight, large size and unpleasant noise. Shape memory alloys (SMAs) offer a solution to address these issues due to their favorable characteristics, such as lightweight, high actuation force and small form factor. However, most existing SMA-based hinge actuators rely on...

Designing an interactive hinge with shape memory alloys and polymers

This research aims to design and simulate a hinge consisting of shape-memory alloys and polymers, which can be actuated along two axes. The hinge consists of a shape-memory body that is actuated externally by shape-memory alloy springs. To achieve maximum deformation, two small single hinges are made, of which the body has the shape of a plate...

Effect of Heat Treatment on Microstructure and Mechanical Behavior of Additively Manufactured Nitinol Shape Memory Alloys

Nitinol shape memory alloys (SMAs) have a unique combination of shape memory capability, making it an attractive material for various engineering and biomedical applications. Additive manufacturing (AM) by laser powder bed fusion (L-PBF) allows to produce Nitinol net shape parts, which broadens its applications. Due to the high heating and...

A new bone-cutting approach for minimally invasive surgery

Aims: Resection of bone is performed in over 75% of all orthopaedic procedures and the electrically powered oscillating saw is commonly used to cut bone. Drawbacks are relatively large incisions and tissue damage due to overshooting often occur. Therefore, the goal of this study is to develop an improved bone-cutting system that has minimally...

Predictive analytical modelling and experimental validation of processing maps in additive manufacturing of nitinol alloys

Nitinol (NiTi) shape memory alloys fabricated by Laser Powder Bed Fusion (L-PBF) Additive Manufacturing (AM) have attracted much attention in recent years, as compared with conventional manufacturing processes it allows to produce Nitinol parts with high design complexity. Avoidance of defects during L-PBF is crucial for the production of...

Design of compliant joints for large scale structures

Large scale structures can benefit from the design of compliant joints that can provide flexibility and adaptability. A high level of deformation is achieved locally with the design of flexures in compliant mechanisms. Additionally, by introducing contact-aided compliant mechanisms, nonlinear bending stiffness is achieved to make the joints...

Design and Computational Modelling for a Shape Memory Alloy-based Adaptronic Architecture

In the EU, the heating and cooling of buildings consumes 14% of all energy. This is a major consumer for one type of activity, and it is compounded by the fact that 75% of it is sourced from fossil fuels. The thoughtful design of facades play a major role in the reduction of heating and cooling energy loads, and the reduction of both...

An Instrument for Matching Defect and Implant Size in Matrix-induced Autologous Chondrocyte Implantation

Cartilage defects in the knee lead to limitations in the daily life of a large group of people in the worldwide population. Research on the treatment of cartilage injuries has lead to various clinical procedures, one of them being Matrix Induced Autologous Chondrocyte Implantation (MACI). MACI surgery consist of two procedures. During the first...

Nitinol Drug Eluting Surfaces for Coronary Stents

Nowadays, drug eluting stents (DES) are the treatment of choice for de novo atherosclerotic lesions. Novel DES are shifting to polymer-free (PF) drug delivery in order to avoid the problem of late stent thrombosis associated with long term polymer presence in the vessel lumen. The scope of this study was to assess the potential of a microporous...