On-going Research Projects

Design of a Product Platform to Improve Commonality for Local Electronic and Home Appliance Industry

(ITF Project)

Industrial collaborator : Mr. P. Leung (IDT International Ltd);
Academic collaborators : Lorraine Justine (Head, School of Design, HKPolyU); Prof. N. Jun (University of Michigan,USA)

Many local and Mainland’s product design and engineering companies find it difficult to maintain commonality and economies of scale in products with strict customer design requirements that may vary greatly from contract-to-contract or piece-to-piece. These strict and varied requirements typically results in highly customized products that are costly to manufacture, involve small production runs, and require long delivery times.

In this research project, we target on developing a product family-based design platform to facilitate the design and manufacturing process of electronic and home appliances using product family design concept, for our local and Mainland’s product design and manufacturing industry using a novel SMARTEAM technology. This platform is a base of collecting, consolidating and analysing all necessary information including components, knowledge, requirements, technologies and standards for a series of products, to build product architectures that can reduce the number of parts in products and time to manufacture and assemble the products, and streamline and simplify the conceptual design and embodiment design phases through the reuse of previous parts, components and ideas.


Design of a multifunctional sensory product for stroke patients

Academic collaborator: Prof. C.W. Chan (Head, Department of Rehabilitation Scineces, HKPolyU)

This project aims at designing a multifunctional sensory product for stroke patients in order to enhance their rate of recovery by going through different stages of physical sensory treatments. According to an annual statistic data from the Hong Kong Department of Health, stroke is one of the most serious problems starting from the middle age people to elderly in Hong Kong. It deprives 3,000 to 3,500 people’s lives every year, and also brings on many other social problems due to malfunction of some muscular tissues and nerve cells in human body. To alleviate the burden of the society and also assist the stroke patients to recover, it is necessary to design some portable multi-functional products for the patients to conduct regularly sensory exercise. This product can irritate the nerve cells and tissues of the patients in order to enhance their sensitivity of the sensory system in the body.


Computational and Experimental Study on the Design of Composite Guardrail Structures for Highway Safety Applications

Industrial collaborator : Mr. C. K. Chan (Highways Department Hong Kong)
Academic collaborator : Prof. K. Y. Fung (Department of Mechanical Engineering, HKPolyU)

This project aims to design and fabricate roadside safety guardrails using advanced composite materials through computational and experimental approaches. The guardrails are designed to avoid an impacting vehicle penetrating the rails, overturning or having its speed abruptly reduced. This demands that the rails must carry the applied loads for the time duration of the impact without the occurrence of catastrophic failure. At the same time, the rail needs to dissipate the vehicle’s kinetic energy in a controlled fashion. In the current study, a series of impact and quasi-static tests on several laboratory-size composite guardrail structures will be conducted. The computational simulation will be used to simulate the crashworthiness behaviour of safety rail systems to assist the design of the rails’ configuration and dimension. Different types of composite preform systems will be considered to avoid delamination, surface spallation and laminate penetration that constitute various modes of failure after resulting from impact loads.


Development of a high-strength nanoclay reinforced advanced composite material for product and engineering applications (ITF Project)

Industrial collaborator: Alvin M. Cheng (CHEMATCO Ltd.)

Advanced composite materials, such as glass fibre and carbon fibre reinforced polymers has been widely adopted by different engineering industries for many years. The major drawback of these materials to be used as primary and secondary structural components is their poor interlaminate shear strength. Debonding between plies may occur easily when they are subjected to external impact. As the crisis of fuel price escalation continues, many structural components, particularly those used inside automobiles (hybrid cars) and aircraft (Boeing 787 and Airbus 380) are increasingly made by light and strong materials. Therefore, this project aims at developing a high delamination and impact resistant, and high strength glass fibre reinforced polymer composite by using nanoclay acted as nano-fillers to enforce the bonding strengths between the glass fibre and polymer matrix, and plies. Since nanoclay is a very light and low cost material and can be obtained naturally, the use of this material will not give any weight penalty to final products, while at the same time the strength of the products is substantially increased.


Damage detection of composite structures using acousto-ultrasonic and embedded fibre-optic sensor mapping technology.

Industrial collaborator: Mr. Peter K. C. Chan (Photonics Instruments Limited, Hong Kong)

In recent years, embedded fibre-optic sensors as structural health monitoring devices have been widely used in both civil and aerospace applications. Their small physical size and ability to immunize electromagnetic interference lead these sensors to be ideal sensing devices with providing accurate and reliable strain and temperature measurement of structures. Most of the previous works were mainly focused on the static, or at very low vibration frequency strain measurements, and the type and location of damage of the structures could be estimated only when these parameters are initially identified. However, it is hardly applied this technology for structures that are subjected to dynamic loading. In this project, a multiplexed fibre-optic Bragg grating (FBG) sensor mapping system will be developed for composite structures to monitor the health condition of structures basing on their dynamic responses. Any damage, such as delamination may influence the natural frequency and strain mode shape of the structures. The location and size of delamination inside the structures could be estimated by using acouto-ultrasonic technique associated with the sensor mapping system. In this approach, only small volume inside the structures is used to accommodate the FBG sensors. Ultrasonic wave (Lamb wave) will therefore be emitted from the surface of the structures once damages are suspected. The location and size of the damages will then be estimated according to the signal received by the embedded sensors inside the mapping system. Genetic Algorithm (GA) will be used to determine the optimal placement of the multiplexed sensors.


Enhancement of fracture toughness of advanced composite materials using multiwalled coiled carbon nanotubes (MCCNTs).

Academic collaborators: H. L. Li (LanZhou University, China); Prof. D. Hui (University of New Orleans, USA)

Since a strong carbon-carbon bond exists among carbon atoms in carbon nanotubes (hereafter called “nanotubes”), a perfect chemical bonding that would not influence the mechanical properties of the nanotubes, between the nanotubes and polymer matrix is hardly achieved. The latest literature has reported that the interfacial shear stress between the nanotubes and matrix is basically due to the mechanical interlocking, and van der Waals and electrostatic interactions. The Principal Investigator (PI) found that the outermost layer of multiwalled nanotubes that were used to make nanotube/polymer composites was almost pulled out after the composites were subjected to a tensile load. Although nanotubes possess many superior mechanical and electrical properties, a weak-bonding interface between the nanotubes’ surface and matrix makes these nano-fillers ineffective when used for composite structures. This project aims to develop multiwalled coiled carbon nanotubes (MCCNTs) as nano-fillers to enhance the fracture toughness of polymer-based composites. The configuration of the nanotubes’ surface should generate mechanical interlocking between the nanotubes and matrix when the composites are subjected to different mechanical loadings. Desirable MCCNTs with specified coil diameter, number of wall layers and pitch length can be obtained by controlling their growth conditions. Experimental investigations and molecular dynamic simulations will be conducted to perform a detailed study of the interfacial bonding strength and mechanical performance of MCCNT/polymer composites.

 

Micro-mechanical properties of carbon nanotube/polymer composites subjected to cryogenic environment.

Academic collaborators: Prof. D. Hui (University New Orleans, USA); Dr. K. Liao (Nanyang University, Singapore)

Due to the increasing need of micro- and nano-scale devices and structural members in the nano-tech and space industries, the development on polymer-based nanotube composites becomes a great challenge in a coming decade. The nanotubes could be buried into polymer matrix to form high strength materials with providing certain degrees of electrical and thermal conductivity in order to avoid electrostatic charging for aircraft and space applications. This research project aims to study the mechanical performance of nanotube/polymer composites subjected to cryogenic environment through experimental and theoretical approaches. The influences on the mechanical performance and structural stability of the composites, due to the existence of microcrackings initiated from micro/nano-voids inside the composites after cryogenic cycling will be experimentally studied. The phenomenological observation on the crack propagation among the micro/nano-voids and structural integrity inside the composites after cryogenic cycling will be conducted by using electronic microscopes. Theoretical approaches will centre on the understanding the different cracking mechanisms of the composites subjected to cyclical cryogenic contraction.

Product and Engineering Design:
Smart Structures, Nanocomposites and Biocompoosites:

Emerging Computer-aided Technology for Supporting the Growth of Automotive Engineering Industry in China (article)

 

Industrial collaborators: Ms. Fanny Lau and Han Li (ANSYS-China);
Academic collaborators: Augustine Lo (ME, PolyU) and Paul Iliffe (Imperial College London, UK)

The demand on developing advanced technology to support the growth of the Automotive Engineering industry is in urgent need. Since Hong Kong has not been a manufacturing hub of Asia for quite a while with most manufacturing works being shifted up into China, the dependence on production of automotive parts and components has become unrealistic in maintaining the past profits of local automotive engineering and design related companies. The development of high technologies through collaborative research and/or adopting up-to-date computer-aided facilities to support the design of automotive parts and components will become the future course of this area. In this project, much effort has been put into the use of computer modelling, simulation and analysis to study the crashworthiness and safety of a vehicle. The integration of knowledge among structural design, fracture mechanics, materials sciences, biomechanics and physiology is needed. This project is mainly focused on two aspects on the safety of vehicle design, they are (i) airbag design and (ii) vehicle safety and crashworthiness.

 

Development of a high-strength and eco-friendly CFF/PEC composite (ITF Project)

Industrial collaborator: Clement Lu ( EBM Biodegradable Bags Co., Ltd.)

Recently, the mankind has realized that unless environment is protected, he himself is threatened due to the run out of natural resources. Conservation of forest and optimal utilization of agricultural and other renewable resources like solar energy and seawater has become compulsion. In this view, the use of renewable resources becomes an important design criterion for all kinds of bio-medical and engineering applications. The usage of disposed raw materials into useful products will be an additional advantage to save the environment from pollution. Animal based natural materials such as silks (from cocoons), wool and chicken feather fibers (CFFs) have attracted much attention to all researchers. CFFs are composed of keratin and protein that are found similar to wool. A recent survey has reported that a chicken processing plant produces about 4000 pounds of chicken feather every hour, which is either used as feather meals or directly-disposed away. CFFs are low density, good thermal and mechanical properties which make them becoming a potential reinforcement for producing high-strength polymer-based composites. In this project, a comprehensive study on the interfacial bonding characteristics, dispersion and mechanical properties of CFF/PEC biocomposites will be conducted through experimental and theoretical approaches.

Development of a high strength biodegradable composite using natural silk fibres

With the strong emphasis on environmental awareness, it has brought much attention in the development of recyclable and environmentally sustainable composite materials since the last decade. Environmental legislation as well as consumer demand in many countries is increasing the pressure on manufacturers of materials and end-products to consider the environmental impact of their products at all stages of their life cycle, including recycling and ultimate disposal. Natural fibres, because of their naturally renewable, imbedded into bio-degradable polymeric materials, can produce a new class of biocomposites. Recently, animal-based natural fibres, such as silk, from cocoons and wool have attracted much attention to all researchers. Silk fibres spun out from silkworm cocoons, consist of a fibroin core surrounded by a protein layer called “sericin”, and these fibres are biodegradable and highly crystalline. It has known that these fibres have higher tensile strength than glass and synthetic organic fibres. Recently, few preliminary studies have reported that the use of these silks, as micro-reinforcements for polymeric materials to form biocomposites can enhance their mechanical and thermal properties, without inducing any un-decomposable wastes and pollutants. In this project, a comprehensive study on the interfacial bonding characteristics, dispersion and mechanical properties of silk fibre/Poly(butylenes succinate)(PBS) biocomposites, at both nano and micro scale levels, will be conducted.