ME Staff Honoured for 2020 Long Service Award

Colleagues of the PolyU Department of Mechanical Engineering (ME) have always been devoting themselves to the development of ME. This year, the Department Head, on behalf of the University, paid tribute to long-serving staff members for their loyal and committed service over the years. Congratulations to the awardees and heartfelt thanks for their years of dedication and devotion which have marked the achievements of the Department. Long Service Award 2020 Award Recipients   Length of Service 　Name   　Post Title 30 years 　Dr W.O. Wong 　黃偉安 　Associate Professor 30 years 　Ms Irene Ngai 　魏愛玲 　Clerical Officer II 25 years 　Mr Raymond Chan 　陳孝曾 　Scientific Officer II 20 years 　Prof. Li Cheng 　成利 　Chair Professor of Mechanical Engineering 20 years 　Ms Merlin Wong 　王倩卿 　Clerical Officer II 15 years 　Prof. Wallace Leung 　梁煥方 　Distinguished Research Professor

ME wins Gold Award at 2021 Inventions Geneva Evaluation Days

Ir Dr Curtis NG (Department of Mechanical Engineering, The Hong Kong Polytechnic University) collaborated with Ir William AU (General Legislation Division of Electrical and Mechanical Services Engineering, HKSAR Government) (EMSD), Avaron Technologies Limited and Anlev Elex Elevator Limited to develop a smart mechanism of “Artificial Intelligent Nylon Optical Fibre Sensing Escalator Combs”.  The project achieved an outstanding result at the 2021 Inventions Geneva Evaluation Days, winning a Gold Medal.  By making use of 3D scanning and printing technology, a conventional escalator metal comb has been transformed into an A.I. monitor using optical fiber sensing and artificial intelligence cloud analysis technology. This real-time detection technology via mobile applications has greatly reduced the occurrence of escalator accidents. Safe and reliable escalators are essential to maintain efficient accessibility and functional vertical transportation in Hong Kong.  Escalators offer tremendous convenience to our society. Breakdowns in escalator operation induce unexpected delays in daily activities and user discomfort.  Therefore, ensuing escalator safe operation is of premier concern.  According to the statistics of escalator incidents, apart from passenger behaviour, the major factor in most of the cases is the intrusion of small foreign objects such as screws and coins into gaps between combs and step treads, causing collision damages and injuries.  The objective of this project is to reduce unnecessary escalator incidents and passenger injuries. The project started with re-engineering the escalator comb design by 3D scanning technology, then the simulation and adoption of new nylon material by multi-jet fusion (MJF) 3D printing technology to enhance its mechanical properties, especially for its ductility and resilience.  The feature of the warning message “Mind the Steps” has been printed on the comb surface to attract public safety awareness.  In a pilot test, the excellent resilience nylon combs successfully bounced all 8 screws from the escalator step to the platform.  In the test, the intrusion of screws did not cause any failure of the nylon combs. To summarize, the main advantages of the re-engineered 3D printed nylon combs are: less possibility of intrusion or trapping of foreign objects due to redesign for minimizing comb clearance; lower risk of high-energy fracture and ejecting of broken metallic pieces because of the use of ductile and compliant MJF 3D-printed nylon; and additional freedom (with almost negligible cost) to have tailor-made features (e.g., reduced clearance, different colors, the addition of alert message) due to the MJF 3D printing technology. The recognition ME achieved is not only a testament to the Department’s research excellence, but also demonstrates the strength of ME in transforming research breakthroughs into real-world solutions.

Dr Yao Haimin receives Materials Genome Engineering Outstanding Reviewer Award 2020

Dr Yao Haimin, Associate Professor of the Department of Mechanical Engineering, has been named the recipient of the Outstanding Reviewer Award 2020 for Materials Genome Engineering by the Universal Wiser Publisher. The Materials Genome Engineering (MGE)  Outstanding Reviewer recognition is given annually to commend the top reviewers for their outstanding reviewing work over the past year. The award recognizes individuals who have provided exemplary efforts to assess the validity, quality and originality of manuscripts published by MGE. Outstanding Reviewers are those who provide excellent, prompt and productive feedback to authors for further improvement. Outstanding Reviewers are also those who frequently review for the journal, and who provide the Editors with constructive advice about the submissions they review. Recipients of the MGE Outstanding Reviewer Award are recognized by the Editorial Office of Universal Wiser Publisher, Outstanding Reviewer Certificates are granted in recognition of their invaluable contribution to the progress of science. Learn more … https://ojs.wiserpub.com/index.php/MGE/announcement/view/100 https://ojs.wiserpub.com/index.php/MGE/

ME Student and Graduate Teams scored Champions at Hong Kong Techathon 2021

Mechanical Engineering (ME) undergraduates and research postgraduates together with students/graduates from other department or university have formed 2 teams to join a start-up competition, the Hong Kong Techathon 2021. There were 4 divisions at the competition, and ME won in 2 divisions. Team ‘ing” with graduates from PolyU ME (Mohammad Shehzaad, Rudra Someshwar) and School of Design, and HKU with the topic of “Feelit” won the Overall Champion and Champion (Health and Social Impact). Team “FJ005” with PhD and MSc students from PolyU ME (Wen Weisong, Ng Hoi Fung) and graduates from Department of Aeronautical and Aviation Engineering with the topic of “Indoor visual positioning system for IoT applications” won the Champion (Smart City). Hong Kong Techathon is a competition for programmers, engineers, designers, marketers, and entrepreneurs to present their business solution ideas and prototypes. Competitors of over a hundred groups from different universities pitched for seed fund and incubation support. This year, the Division has provided one-week online workshops and programmes (2-9 January 2021) guiding participants to brainstorm new business solutions and presenting their ideas to renowned academic and industrial panelists.

ME researchers’ innovative micro-manufacturing as the cover feature on the top journal IJMTM

Prof. Mingwang Fu’s recent paper, co-authored with Chair Prof. Sanqiang Shi and postdoctoral researcher Dr XF Tang as the first author, was featured as the cover of the International Journal of Machine Tools and Manufacture (IJMTM) for three issues from January to March of 2021. IJMTM is the top one journal in manufacturing with the impact factor of 8.019. The paper entitled “interactive effect of grain size and crystal structure on deformation behavior in progressive micro-scaled deformation of metallic materials” was published in IJMTM in January 2020 and reported the findings of the interactive effect of grain and geometry sizes and crystal structure on the process behavior, performance and the quality and properties of the parts made by the unique deformation-based micro-manufacturing process. It also summarizes the development of an innovative process and the scientific understanding and insight into the nature of the effects of microstructure and geometrical sizes and the crystal structure of materials to provide a basis for process innovation and process and quality optimization. This research is a hot topic in micro-manufacturing as it involves multi-disciplines covering micro-mechanics, materials and manufacturing sciences. The journal of IJMTM selects four best papers from all the papers published in the journal each year to be featured as the cover of the journal and each cover is used for three months. The paper to be featured by the journal comes from the NSFC key project with the funding of RMB 3 million of which Prof Mingwang Fu is the principal investigator of the project. Nowadays, micro-manufacturing has become an important manufacturing process for making micro-scaled parts and structures to meet the huge demands from different industrial clusters due to the upward trend of product miniaturization. Micro-forming is one of the micro-manufacturing processes to be widely used in industries for its high productivity, low cost and good properties of the fabricated parts and structures. However, there are many unfathomable and bottlenecked issues from different aspects including innovative process development, process parameter optimization, product quality assurance and properties tailoring. On the other hand, it is very difficult, if not fully impossible, to leverage the data, information and knowledge developed in the traditional macro-scaled manufacturing to micro/nano-manufacturing since they are not fully valid in the downscaled domains. Successfully addressing these issues needs to have an in-depth understanding and scientific insight into the physical essence and nature of the process. The paper published in IJMTM aims at addressing these issues and providing a basis for large-scale application of the process. Read more at https://doi.org/10.1016/j.ijmachtools.2019.103473. XF Tang, SQ Shi, MW Fu, Interactive effect of grain size and crystal structure on deformation behavior in progressive micro-scaled deformation of metallic materials, International Journal of Machine Tools and Manufacture 148 (2020) 103473.

Professor Li Cheng elected Distinguished Fellow of IIAV

Prof. Li Cheng, Chair Professor of Mechanical Engineering of the ME department has recently been elected a Distinguished Fellow of the International Institute of Acoustics and vibration (IIAV). IIAV Distinguished Fellowship is awarded to those individuals who have distinguished careers in acoustics and/or vibration. Receiving a such title, Prof. Cheng becomes one of the eleven outstanding individuals that IIAV has ever elected to such a prestigious grade. IIAV is an international society with members from all over the world. The purpose of the IIAV is to advance the science of acoustics and vibration by creating an international scientific society that is responsive to the needs of scientists and engineers in all countries whose primary interests are in the fields of acoustics and vibration. IIAV organizes an annual premier world event, the International Congress on Sound and Vibration (ICSV), which combines all areas of acoustics, noise and vibration. ME department was the host of 8th edition of the ICSV in 2001. Through his work, Prof. Cheng is recognized by IIAV as an internationally renowned researcher and engineering practitioner. He made seminal contributions to the advancement of knowledge in the area of acoustics and vibration. In addition to a large number of high-quality scientific contributions, his research has had direct impact on solving engineering problems through close collaboration with industry. Prof. Cheng has a prolific record of contributions to scholarly and professional organizations including IIAV as a former Fellow and a current Board Director. Another recent appointment: Prof. Li Cheng was appointed as the Vice-President Asia Pacific by the I-INCE board (International Institute of Noise Control Engineering).

ME researchers developed new alloys with ultrahigh strength and large ductility published in Nature Communications

Advanced structural materials with ultrahigh strength and excellent ductility are highly desirable for a wide variety of technological applications, including aerospace, transportation, and energy industries. However, ultrahigh-strength materials typically suffer from low tensile ductility, which severely limits their practical utility. Recently, a research team led by Dr JIAO Zengbao, assistant professor of PolyU Department of Mechanical Engineering, developed an innovative design concept for high-performance materials by engineering nanolamellar architectures, which leads to the development of new bulk nanostructured materials with an unprecedented combination of over 2 GPa yield strength and 16% uniform tensile ductility at ambient temperature. The extraordinary mechanical properties of the newly developed alloys offer tremendous potential for structural applications in aerospace, automotive, and energy industries. In addition, the fundamental concept of lamellar architecture engineering can be applied to many other metallic materials, including new-generation superalloys, titanium alloys, and advanced steels, to achieve enhanced properties for specific applications. This work has been recently published in Nature Communications [“Ultrahigh strength and ductility in newly developed materials with coherent nanolamellar architectures”, https://www.nature.com/articles/s41467-020-20109-z]. Mr FAN Lei, PolyU ME PhD student is the first author, and Dr JIAO Zengbao is one of the corresponding authors.

Benchmark advance in vehicle suspension control: Better vibration suppression & Less energy cost

PolyU research team led by Dr XJ Jing from the Laboratory of Nonlinear Dynamics, Vibration and Control, Department of Mechanical Engineering, takes further steps into critical industrial issues with benchmark advance achieved recently of increasing industrial impact. A series of benchmark results are recently developed and some of them have been accepted and published in: IEEE Transactions on Industrial Electronics (IF7.515, Rank 1/64 in Instrument and Instrumentation), which is a flagship journal in the area of industrial electronics and control: https://ieeexplore.ieee.org/abstract/document/9280376 IEEE Transactions on Cybernetics (IF11.079, Rank 1/63 in in Control and Automation), which is a flagship journal in the area of control theory and methods): https://ieeexplore.ieee.org/abstract/document/9013024   In the past several decades, suspension systems, as a critical part of vehicle chassis, which can perform significant influence on the ride comfort and vehicle manoeuvrability, obtained more and more popularity and attention in automotive industry. Compared with passive and semi-active suspension systems, an extra actuator is installed in an active suspension system to generate or dissipate energy; and thus, much better vibration isolation effect can be obtained. However, the energy cost and tough requirements on efficiency, robustness and reliability of actuation systems are becoming more and more critical issues in practical application (Figure 01). Traditional control methods usually only target at high performance without sufficient consideration on the energy cost, and thus have obvious limitation in various practical applications. To solve the problem, Dr Jing’s research team established a unique adaptive and robust control scheme for active suspension systems with neural networks, fuzzy logic and/or others. The new control scheme can intentionally employ inherent nonlinear dynamics of vehicle systems and address several critical engineering issues simultaneously, including energy efficiency, input delay/saturation, loading change, and/or unknown/uncertain dynamics etc, which are all challenging problems in engineering practices. The significant difference from most existing controllers lies in that, the designed controller can effectively utilize beneficial nonlinear stiffness and damping characteristics introduced by a novel bioinspired reference model (Figure 02), and thus purposely achieve superior vibration suppression and obvious energy-saving performance simultaneously. Theoretical analysis and experimental results vindicate that the proposed controller can effectively suppress vibration with much more improved control performance and considerably reduced control energy consumption up to or more than 44% (Figure 03, Table 01). This should be for the first time to reveal both in theory and experiments that a superior suspension performance is obtained with simultaneously an obvious control energy saving, by employing beneficial bioinspired nonlinear dynamics, compared to most traditional control methods. It also provides a unique insight into many other robust controller designs in various engineering issues. Table 01: RMS OF THE ENERGY CONSUMPTION WITH RESPECT TO DIFFERENT ROAD PROFILES (W) 　Controller 　Sinusoidal road profile 　Random road profile 　ESOT controller 　0.031 　0.0027 　Proposed controller 　0.0264(↓14.84%) 　0.0021(↓22.22%) 　Proposed tracking controller 　0.0125(↓59.68%) 　0.0015(↓44.44%)   The industrial potential will be further explored by collaborating with automobile companies from mainland of China, including the GAC Group, which is a Chinese automobile maker headquartered in Guangzhou, Guangdong, and a subsidiary of Guangzhou Automobile Industry Group. Detailed technical collaboration is under negotiation.

Nurturing Young Researchers in ME

The Department is one of the most research-active departments in the PolyU, excelling in a number of research areas of strategic importance germane to Hong Kong. We aspire to carry out high quality research of both fundamental and applied nature, nurturing researchers and striving for building up expertise in emerging areas. Around 250 research students or personnel led by 30 academic supervisors, ME researchers are dedicating themselves to a wide spectrum of research areas including Advanced Materials and Processing, Aerospace Engineering, Clean Energy and Energy Storage, Robotics and Control, Sound and Vibration, Thermofluids and Combustion. Every year, the Department organizes the Research Presentation Competition for the ME research students to share their research project insights with their peers and the PolyU community, and let their talents be known. In Nov 2020, two research students were awarded the Champions for their excellent research works and fabulous presentations in the 6th ME Research Presentation Competition. Research Stories of 2 Champions FANG Jieyichen PhD in Mechanical Engineering Supervisors: Dr JIAO Zengbao & Prof. FU Mingwang Research interest: High-temperature alloys Research work: High-entropy alloys (HEAs) are newly emerging advanced metallic materials with unique microstructure and excellent mechanical properties. In contrast to conventional alloys with one primary element and several minor alloying dopants, HEAs typically contain four or more multiple principal elements. Precipitation-hardened HEAs, especially those strengthened by coherent L12-nanoparticles, have enabled a new space for the development of advanced structural materials with superior mechanical properties at both room and high temperatures. From the application and processing points of view, there is a temperature-rise and down period which will affect the entropy contribution and solid solubility. Therefore, understanding phase stability and transformations at intermediate temperatures is crucial for tailoring microstructures and mechanical properties of L12-strengthened HEAs. In this study, the crystal structure, morphology, chemical composition of nanoscale precipitates and matrix of L12-strengthened HEAs at different temperatures were systematically investigated through scanning electron microscopy, X-ray diffraction, atom probe tomography, and thermodynamic calculations. Our results reveal that L12 precipitates can be formed at all the studied temperatures, but their morphology change as the aging temperatures decreases. In addition, the matrix structure changes from fcc-type to bcc-type upon long-term annealing at relatively low temperatures. The microstructural evolution and phase transformations of these alloys were discussed from the thermodynamic and kinetic points of view. This research not only sheds light on fundamentals of phase stability and transformations at intermediate temperatures but also provides guidance for microstructural control of L12-strengthened high-entropy alloys. SHI Xingyi PhD in Mechanical Engineering Supervisor: Dr AN Liang Research interest: Fuel cells Research work: In the last decade, the rising demand for the utilization of renewable energy has drawn more and more attention to energy conversion and storage systems. Among various energy conversion systems, direct liquid fuel cells (DLFCs) with their high energy density and facile fuel storage have received increasing attention. However, most of DLFCs must use noble metal catalysts for liquid fuel oxidation reactions, but yield limited fuel cell performance, greatly hindering their widespread application. Recently, an electrically rechargeable liquid fuel (e-fuel) system, typically consisting of an e-fuel charger for energy storage and an e-fuel cell for power generation, has attracted worldwide attention.1 Compared to the conventional alcoholic liquid fuels, this liquid e-fuel offers three major advantages including: i) good rechargeability, ii) high electrochemical reactivity even on carbon-based materials; and iii) good cost-effectiveness and durability. Here, we report a power generation system, direct liquid e-fuel cell,2 consisting of a catalyst-free graphite-felt anode and a conventional oxygen cathode separated by a proton exchange membrane, resulting in a maximum current density of 750 mA cm−2, a peak power density of 293 mW cm−2, and an energy efficiency of 42.3% at room temperature, which is much higher than the performances achieved by conventional direct liquid fuel cells, as shown in Fig. 1. This emerging technology, capable of fast recharging, could be a powerful, efficient, cost-effective, and durable power generation device, showing great potential for commercialization in the future fuel cell electric vehicle industry (Fig. 2).      

The 6th ME Research Presentation Competition 2020

The 6th PolyU Mechanical Engineering Research Presentation Competition was successfully held at the Lecture Theatre in the Jockey Club Innovation Tower, PolyU, on 19 Nov 2020. It is an annual event for research students to display their research project results and share knowledge with the PolyU community. This year, it was an unprecedented period to organize the event. Considering the social distancing measures on COVID-19, the function was confined to the competition participants and the department staff. It was not open to others. Instead of voting for the competition based on popularity, we formed a panel of judges by ME academic staff. Twenty-three research student participants each delivered a high-impact brief presentation within 3-minute. With their professional and animated presentation materials, most of the participants demonstrated good academic pitching skills. The panel of judges was impressed by the performance of the participants this year. After the oral presentations, participants interacted with the panel individually in the research posters exhibition. Displayed posters not only highlighted their research project results, but it was also an occasion for participants to convey their ideas, communicate with professionals, and let their talents be known. Congratulations to their fabulous presentations and excellent research work! Champion Student: Miss FANG Jieyichen Supervisor: Dr JIAO Zengbao Title: Stability of precipitation strengthened high-entropy alloys at intermediate temperatures Champion Student: Mr SHI Xingyi Supervisor: Dr AN Liang Title: Energizing Fuel Cells with an Electrically Rechargeable Liquid Fuel 2nd Runner-Up Student: Mr ZHAO Qingxiang Supervisor: Dr Henry CHU Title: A Soft Pipe-Climbing Robot Merit Student: Mr ARIF Muhammad Irsalan Supervisor: Dr Randolph LEUNG Title: Study of Passive Methods for Airfoil Tonal Noise Reduction using Fluid-Structure Interactions Merit Student: Mr WEN Weisong Supervisor: Prof. WEN Chih-Yung Title: 3D LiDAR Aided GNSS and Its Tightly Coupled Integration with INS Via Factor Graph Optimization Merit Student: Mr ZHOU Pengyu Supervisor: Prof. SU Zhongqing Title: An inkjet-printed, flexible, ultra-broadband nanocomposite film sensor for ultrasonics-based health monitoring More photos on PHOTO GALLERY