J. Y. H. Fuh

National University of Singapore | NUS · Department of Mechanical Engineering

In the field of complex systems, self-organization magnifies the compounding effects of element interactions by propagating, modifying, and enhancing functionality, ultimately leading to emergent system properties. The intricacies of self-organization make unveiling the elusive link between element interactions and emergent system properties akin t...

This paper delves into the potential of Large Language Model (LLM) agents for industrial robotics, with an emphasis on autonomous design, decision-making, and task execution within manufacturing contexts. We propose a comprehensive framework that includes three core components: (1) matches manufacturing tasks with process parameters, emphasizing th...

As the influence of Incremental Sheet Forming (ISF) grows in manufacturing sectors, so does the demand for precise and updated knowledge construction in this domain. In this research, we evaluate the capability of Large Language Models (LLMs) to capture domain-specific knowledge, using ISF as a case study. Recognizing common LLMs' limitations such...

Surface microscopic characterization of additive manufacturing samples is necessary because of unavoidable defects in the as-printed components. However, the samples are inevitably damaged during characterization when using current methods. Herein, we propose a measurement method using a digital microscope to obtain three-dimensional (3D) morpholog...

Purpose To develop a novel 3D printable polyether ether ketone (PEEK)-hydroxyapatite (HA)-magnesium orthosilicate (Mg2SiO4) composite material with enhanced properties for potential use in tumour, osteoporosis and other spinal conditions. We aim to evaluate biocompatibility and imaging compatibility of the material. Methods Materials were prepared...

Purpose To manufacture and test 3D printed novel design titanium spine rods with lower flexural modulus and stiffness compared to standard solid titanium rods for use in metastatic spine tumour surgery (MSTS) and osteoporosis. Methods Novel design titanium spine rods were designed and 3D printed. Three-point bending test was performed to assess me...

Bioelectricity has been a fundamental property of all living organisms. With electrical stimulation, living cells can interact with their microenvironments, which makes electrical stimulation highly beneficial for various biomedical applications. However, traditional electrical stimulation mainly relies on bulky and complex equipment, which may not...

4D printing of metallic shape‐morphing systems can be applied in many fields, including aerospace, smart manufacturing, naval equipment, and biomedical engineering. The existing forming materials for metallic 4D printing are still very limited except shape memory alloys. Herein, a 4D printing method to endow non‐shape‐memory metallic materials with...

Additive manufacturing of metallic glass has attracted great attentions from researchers owing to the prospect of free-form fabricating high-performance bulk amorphous alloy parts. The characteristics of additive manufacturing from points to tracks, tracks to layers, and layers to parts are suitable for forming complex bulk metallic glass parts, wh...

Leaf photosynthesis, coral mineralization, and trabecular bone growth depend on triply periodic minimal surfaces (TPMSs) with hyperboloidal structure on every surface point with varying Gaussian curvatures. However, translation of this structure into tissue-engineered bone grafts is challenging. This article reports the design and fabrication of hi...

Micro-selective laser melting fabricated triply periodic minimal surface sheet lattice and epoxy interpenetrating phase composites (IPCs) are investigated in this paper. To achieve superior specific energy absorption (SEA) enhancements in the composites, an optimised Schwarz primitive lattice (P-lattice) structure is proposed by redefining the shel...

The unique properties of bulk metallic glass (BMG) make it an excellent potential material for bone implant application. It is difficult to directly produce BMG samples due to the critical cooling rate of molding. The advancement of additive manufacturing technologies, such as selective laser melting (SLM), has enabled the development of BMG. The s...

Ti-6Al-4V is one of the popular choices for biomedical implants due to multiple advantages, such as corrosion resistance, high strength-to-weight ratio, biocompatibility, lightweight, durability, and osseointegration properties. However, Young’s modulus (E) of Ti-6Al-4V is much higher than the E of natural human bone, which may lead to stress shiel...

Metallic lattice structures can be fabricated by selective laser melting (SLM) with purposefully designed pores and controlled pore sizes that can bio mimic the natural bone, providing adequate mechanical and biological support for the patients. Strut-based structures, like Cubic, Octet; and sheet-based structures, like triply periodic minimal surf...

Lattice structures are widely used in orthopedic implants due to their unique features, such as high strength-to-weight ratios and adjustable biomechanical properties. Based on the type of unit cell geometry, lattice structures may be classified into two types: strut-based structures and sheet-based structures. In this study, strut-based structures...

Various studies have reported 3D printing of superelastic nitinol parts. However, the sizes of samples are several scales larger than those in the biomedical applications, which provides insufficient values for the industry use. To investigate the feasibility of SLM fabrication of thinner nitinol medical devices, i.e., stent, this study has systema...

Since various build defects in the Selective laser melting (SLM) process are found to be associated with the instability of melt pool, the melt pool monitoring is particularly important for the final product quality control. Previous studies focus on the geometric features to describe the changes of the size and shape of melt pool, which are not su...

3D printing technology has increasing applications in spine surgery due to its many realized and potential benefits. This review aims to explore the current and future potential of 3D printing technology in various aspects of spine surgery. The ability of 3D printing technology to geometrically mimic spinal anatomy enables the manufacturing of real...

Understanding precipitation behaviors of laser directed energy deposition (L-DED) Nb-Si-based in-situ composite is significant to tailor the microstructure and performances. Here, FCC-Ti and α-Nb5Si3 precipitates are formed in Nb-based solid solution(Nbss) of as-built Nb-24Ti-15Si alloy, and the orientation relationships (ORs) between precipitates...

Laser powder bed fusion (LPBF), one of the most powerful additive manufacturing techniques, has attracted broad interests from medical, aerospace and automotive industries. It is a powder bed fusion method, processing metallic and non-metallic materials in a layer-by-layer manner. However, such a layer based manufacturing process introduces interna...

Laser-based Additive Manufacturing System Monitoring and Control: Theory and Applications

Purpose-This study aims to develop a data fusion method for powder-bed fusion (PBF) process monitoring based on process image information. The data fusion method can help improve process condition identification performance, which can provide guidance for further PBF process monitoring and control system development. Design/methodology/approach-Des...

Triply periodic minimal surface (TPMS) sheet lattice structures are composed of continuous and smooth shells, enabling the achievement of a high surface-to-volume ratio and pore interconnectivity, which represent an emerging solution for lightweight applications. In this study, an improved Schwarz primitive lattice (P-lattice) structure was propose...

In recent times, 3D printing has been gaining traction as a fabrication platform for customizable drug dosages as a form of personalized medicine. While this has been recently demonstrated as oral dosages, there is potential to provide the same customizability and personalization as topical applications for wound healing. In this paper, the applica...

The metal-based additive manufacturing (MAM) processes have great potential in wide industrial applications, for their capabilities in building dense metal parts with complex geometry and internal characteristics. However, various defects in the MAM process greatly affect the precision, mechanical properties and repeatability of final parts. These...

Daily walking or exercise of the bone implant recipients may generate particles due to wear and tear. Reports have mentioned that particles could circulate in the human body and trigger aseptic loosening, inflammation, and other potential complications. The mechanism of these phenomena remains mostly unclear. This study is to investigate the cytoto...

Path planning is an important task in laser aided additive manufacturing (LAAM). The sliced 2D layers usually need to be partitioned into sub-regions such that appropriate filling toolpaths can be designed for different sub-regions. However, reported approaches for 2D layer segmentation generally require manual interaction that is tedious and time-...

Considering the variations in burns depending on the circumstances that caused them, the need for personalized medicine and care for burn victims is vital to ensure that optimal treatment is provided. With the level of accuracy and customization that 3D printing brings as a technology, there is potential in its use to fabricate wound dressings that...

The complex and hierarchical structure with high vascularization of human bone limits the applications of traditional bone tissue engineering, especially in large bone defects. Progress in nanotechnology and 3D printing has opened new opportunities for bone tissue engineering. Nanoparticles possess unique size-dependent physicochemical and mechanic...

The cover image is based on the Article 3D bioprinting and microscale organization of vascularized tissue constructs using collagen‐based bioink by Senthilkumar Muthusamy et al., https://doi.org/10.1002/bit.27838.

“Metastatic Spine Disease” (MSD) often requires surgical intervention and instrumentation with spinal implants. Ti6Al4V is widely used in metastatic spine tumor surgery (MSTS) and is the current implant material of choice due to improved biocompatibility, mechanical properties, and compatibility with imaging modalities compared to stainless steel....

The additive manufacturing (AM) has met a big challenge on account of customized shapes, especially complex and articulated models, designed by traditional approaches. For realizing AM processing, the reuse, matching, and modifications of the existing 3D digitized models are prerequisite to the applications which also avoid designing from start. In...

Bioprinting three‐dimensional (3D) tissue equivalents have progressed tremendously over the last decade. 3D bioprinting is currently being employed to develop larger and more physiologic tissues, and it is of particular interest to generate vasculature in biofabricated tissues to aid better perfusion and transport of nutrition. Having an advantage...

Heat accumulation is a critical problem in continuous multi-layer laser aided additive manufacturing (LAAM) process, resulting in inhomogeneous mechanical properties and non-uniformity in the deposited height which can deteriorate the deposition process. This work presents a new integrated finite element (FE) simulation and machine learning approac...

Additive manufacturing (AM) technology has rapidly evolved with research advances related to AM processes, materials, and designs. The advantages of AM over conventional techniques include an augmented capability to produce parts with complex geometries, operational flexibility, and reduced production time. However, AM processes also face critical...

As a promising additive manufacturing method, direct energy deposition has been widely used to fabricate complex thin-walled parts. However, some defects such as uneven layer surface and excessive build-ups always occur in this process. In this study, a high-fidelity model adopting a novel laser/powder source is developed to simulate the detailed m...

Compared with other additive manufacturing processes, the metal-based additive manufacturing (MAM) can build higher precision and higher density parts, and have unique advantages in the applications to automotive, medical, and aerospace industries. However, the quality defects of builds, such as dimensional accuracy, layer morphology, mechanical an...

Importance: Three-dimensionally printed nasopharyngeal swabs (3DP swabs) have been used to mitigate swab shortages during the coronavirus disease 2019 (COVID-19) pandemic. Clinical validation for diagnostic accuracy and consistency, as well as patient acceptability, is crucial to evaluate the swab's performance. Objective: To determine the accur...

In recent years, metal cellular structures have drawn attentions in various industrial sectors due to their design freedoms and abilities to achieve multi-functional mechanical properties. However, metal cellular structures are difficult to fabricate due to their complex geometries, even with modern additive manufacturing technologies such as the d...

In the selective laser melting process, the molten pool flow, particularly the keyhole phenomenon, plays an important role in the pore formation and then influences the mechanical properties. In this study, we develop a 3D numerical model to simulate the keyhole mode in SLM. The transient evolutions of the temperature field, fluid flow, molten pool...

Instrumentation during metastatic spine tumor surgery (MSTS) provides stability to the spinal column in cases of pathological fracture or iatrogenic instability produced while performing extensive decompression. Titanium is the current implant material of choice in MSTS. However, it hinders radiotherapy (RT) planning and generates artifacts with ma...

With the recent advancement in nanotechnology, nanoparticles (NPs) offer an ample variety of smart functions than conventional materials in various aspects. As compared to larger particles, NPs possess unique characteristics and excellent abilities, such as low toxicity, chemical stability, surface functionality, and biocompatibility. These advanta...

Selective laser melting (SLM) is a promising additive manufacturing technology, which involves complex physics such as heat and mass transfer, phase transformation and molten pool flow. In this study, a three dimensional numerical model is developed to model the thermal-fluid flow and to predict the surface morphology for the SLM process. Particula...

Skin regeneration through tissue engineering combines biomaterials compatible with living cells to build a niche of limited duration that can support recapitulating reconstruction of the key features of native human skin. Reconstructed full thickness human skin is a promising platform for studying skin biology and assessing the safety and efficacy...

3D printing is known as a cost-effective technique that shows huge potential in fabrication of graft substitutes for bone tissue regeneration. However, the tradeoff between 3D printability, mechanical strength and bioactivity of the printed materials (i.e., inks) remains a challenge. In this work, we present a novel photocrosslinkable nanocomposite...

Bone defects and diseases are devastating, and can lead to severe functional deficits or even permanent disability. Nevertheless, orthopedic implants and scaffolds can facilitate the growth of incipient bone and help us to treat bone defects and diseases. Currently, a wide range of biomaterials with distinct biocompatibility, biodegradability, poro...

Hybrid implants combine both Titanium (Ti) and Magnesium (Mg) are prevalent nowadays. The long-term implications of Ti and Mg implants within the human body are not yet fully understood. Many implant failure cases due to inflammation, allergic responses, and aspect loosening have been reported frequently. Particles generated through daily wear and...

Path planning is an important task in laser aided additive manufacturing (LAAM).The sliced 2D layers usually need to be partitioned into sub-regions such that appropriate filling toolpaths can be designed for different sub-regions. However, reported approaches for 2D layer segmentation generally require manual interaction that is tedious and time-c...

In this study, reverse electrodialysis (RED) and driven RED (dRED) experiments were performed for a wide range of conditions, encompassing different inter-membrane distances (or spacer thicknesses), spacer shadow factors, salinity gradients and flow velocities. A resistances in series (RIS) model was proposed based on average concentrations in the...

Additive manufacturing (AM) is regarded as one of the breakthrough innovations since the 19th century, whose impact on the manufacturing world is recognized as the same with the impact of airplane on the transportation industry [1]. Selective laser melting (SLM), one of the most popular AM techniques for processing metallic materials, has demonstra...

The inkjet 3D printing has been one of the most studied and applied additive manufacturing (AM) processes in electronic industry. In this AM process, the forming quality is greatly influenced by the micro-droplet deposition and substrate temperature. While most studies focus on the formation mechanism of droplets, there are few studies on the quant...

Laser aided additive manufacturing (LAAM) is a key metal 3D printing and remanufacturing technology for fabrication of near-net shape parts. Studying thermal field induced by different scanning strategies is important to evaluate and optimize the resultant residual stress and distortion distribution. However, it is very computationally expensive to...

Numerous bioactive molecules produced in cells are involved in the process of bone formation. We consider that appropriate, simultaneous application of two types of bioactive molecules would accelerate the regeneration of tissues and organs. Therefore, we combined aspirin‐loaded liposomes (Asp@Lipo) and bone forming peptide‐1 (BFP‐1) on three dimen...

A method of hybrid convolutional neural networks (CNNs) was proposed for powder-bed fusion (PBF) process monitoring in this work. The proposed method can learn both the spatial and temporal representative features from the raw images automatically based on the advantages of the CNN architecture. The results demonstrated the superior performance of...

Conductivity is a desirable property of an ideal nerve guide conduit (NGC) that is being considered for peripheral nerve regeneration. Most of the conductive polymers reported in use for fabrication of tissue engineering scaffolds such as polypyrrole (PPy), polyaniline, polythiophene, and poly(3,4-ethylenedioxythiophene) are non-biodegradable and p...

Bioprinting is a novel technology that has a greater potential to revolutionize the field of tissue engineering and regenerative medicine. The growth of this technology is commendable and the applications explored are far and wide, including skin printing, orthopedics, cardiovascular applications, dental and maxillofacial applications, cancer resea...

Ultrasonic vibrations were applied to weld Ni-based metallic glass ribbons with Al and Cu ribbons to manufacture high-performance metallic glass and crystalline metal composites with accumulating formation characteristics. The effects of ultrasonic vibration energy on the interfaces of the composite samples were studied. The ultrasonic vibrations e...

Laser aided additive manufacturing (LAAM) is one of the key metal 3D printing technologies for surface cladding or fabrication of near-net shape parts. The study of LAAM scanning pattern is important to understand their relationship with residual stress and part distortion. This paper proposed a framework to both simulate and evaluate laser scannin...

Bioprinting is increasingly being used for fabrication of engineered tissues for regenerative medicine, drug testing and other biomedical applications. The success of this technology lies with development of suitable bioinks and hydrogels that are specific to the intended tissue application. For applications such as neural tissue engineering, condu...

Over the past decade, 3D printing has been explored as a means of producing human skin mimics for applications such as cosmetics testing, drug screening and wound healing. When it comes to the post-processing step of bioprinting skin, choices in recent times have mainly been the static culture of constructs or the use of perfusion and rotatory bior...

Transdermal drug delivery is widely investigated as an alternative drug administration route to oral delivery and hypodermic injections. Owing to the availability of human skin samples, in vitro tests are used to predict the in vivo delivery of transdermal drugs. The most widely used validation method is skin permeation using diffusion cells. Tradi...

The nine papers in this special section focus on Big Data analytics in intelligent manufacturing systems. These systems can automatically adapt to changing environments and varying process requirements with minimal supervision and assistance from operators. It is essentially a cyber–physical production system that has enhanced intelligence due to l...

It is difficult to produce bulk blanks directly from metallic glass, which limits its application. Ni-based metallic-glass thin strips that can be manufactured easily were used to manufacture bulk metallic glass additively by ultrasonic bonding. The effects of ultrasonic vibration energy on the quality of the additive manufacturing of bulk Ni-based...

Specific structures of esophagus play an important role in specific functions. However, current esophageal tissue engineering scaffolds replicate them poorly. To address this issue, the objective of this study is to fabricate a hierarchical PCL/F127 scaffold inspired by the natural esophageal structure. The hierarchical scaffold consists of aligned...

Bone defects are some of the most difficult injuries to treat in clinical medicine. Evidence from cellular and animal studies suggests that aspirin exhibits protective effects on bone by promoting both the survival of osteoblast precursor stem cells and osteoblast differentiation. However, acquired resistance to aspirin and its cytotoxicity signifi...

Laser deposition strategies can have significant effect on the temperature distribution for multi-bead multi-layered additive manufacturing. Its influence on thermal field will affect the induced residual stress and distortion. In this paper, a computationally efficient numerical model for Laser Aided Additive Manufacturing (LAAM) process was devel...

NGCs are considered as an alternative treatment method for treating peripheral nerve injuries in place of nerve autografts. Biomimicry, conductivity, and biodegradability are the properties expected of an ideal NGC. PCL/PAA NGCs with three different concentrations of PAA (2.5, 5 and 7.5%) were fabricated using EHD-jet 3D printing. The mechanical pr...

Defects among the selective laser melting(SLM) part hinder the development of the SLM process. This work provides an approach to conduct the monitoring and defect diagnosis by support vector machines (SVM) model using extracted features from acoustic signals. After training and testing with the linear SVM model, the result from the Fisher discrimin...