John P. T. Mo is Professor of Manufacturing Engineering and former Head of Manufacturing and Materials Engineering at RMIT University, Australia, since 2007. He has been an active researcher in manufacturing and complex systems for over 35 years and worked for educational and scientific institutions in Hong Kong and Australia. From 1996, John was a Project Manager and Research Team Leader with Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) for 11 years leading a team of 15 research scientists. John has a broad research interest and has received numerous industrial research grants. A few highlights of the projects include: signal diagnostics for plasma cutting machines, ANZAC ship alliance engineering analysis, optimisation of titanium machining for aerospace industry, critical infrastructure protection modelling and analysis, polycrystalline diamond cutting tools on multi-axes CNC machine, system analysis for support of complex engineering systems John obtained his doctorate from Loughborough University, UK and is a Fellow of Institution of Mechanical Engineers (UK) and Institution of Engineers Australia.

Speech Title: Machining of Hard-to-cut Materials by Robots

Abstract: Compared to CNC machine tools, multi-axes Industrial Robots (IRs) suffer from significant vibration and instability if they are required to do machining of metals, due to high forces during cutting and their relatively weak structure. Research has shown that while CNC machines often have stiffness greater than 50 N/μm, IRs usually have less than 1 N/μm. Furthermore, even IRs with a large mass have a natural frequency of around 10Hz and cannot be compared with hundreds to thousands of hertz of CNC machines. On the other hand, due to the IRs’ high degrees of freedom, they can perform machining trajectories in ample 3-dimensional space while keeping an arbitrary position and orientation for any cutting tool. However, the lack of stiffness of IRs have been severely limiting the use of IRs as machining tools for objects with complex shapes.
While conventional CNC machine tools dominate in cutting processes, they do have limitations, especially with hard-to-cut materials such as polycrystalline diamond or boron nitride. Unfortunately, the aerospace and automotive industries are fast adopting high strength to weight ratio materials which are typical much more difficult to be cut or shaped. A new electric discharge machining method has been developed on a conventional tool and cutter grinder machine. The success of machining the hardest materials on earth has revealed several advantages of the new manufacturing process, one of which is the non-touching machining operation. This new finding sparks a new line of research into integrating electric discharge machining process with IRs spatial flexibility while the system does not create any contacting forces that the IRs are most disadvantaged.

Yu-Lung Lo received his B.S. degree from National Cheng Kung University (NCKU), Tainan, Taiwan, and his M.S. and Ph.D. degrees in Mechanical Engineering, University of Maryland, College Park, USA. He has been faculty of the Mechanical Engineering Department, NCKU, since 1996, where he is now a University Chair professor and Vice Dean of College of Engineering / Academy of Innovative Semiconductor and Sustainable Manufacturing. He was Director of Instrument Development Center and Chairman of Department of Mechanical Engineering in NCKU. Also, He was a visiting scientist in University of Michigan, Ann Arbor. Dr. Lo received Research Excellence Award, Ministry of Science and Technology (MOST) in Taiwan, 2018, 2021; Fellow of Chinese Society of Mechanical Engineers (CSME) in Taiwan, 2019; Fellow of Society for Experimental Mechanics (SEM) in USA, 2018; ASE Scholar in Research Excellence, Taiwan, 2017; and Outstanding Award for Professor in Engineering, Chinese Society of Mechanical Engineers in Taiwan, 2013. Also, he received the First-Class Research Award from National Science Council (NSC), 2005/2006, and the Dr. Ta-You Wu Award for Young Researchers from NSC, 2002. He was invited to be an invited speaker, keynote speaker, and plenary speaker in the optics and 3D printing related international conferences, and also organized and chaired section of international conferences, especially General Chair of International Symposium on Optomechatronic Technology in 2017. Now he is Chairman of Asian Society of Experiment Mechanics (ASEM) and executive council member of The American Society of Mechanical Engineers (ASME), Taiwan Section. His research interests include biophotonics, 3D printing on metal powder, and laser machining on semiconductor materials. He has authored over 190 journal publications and has filed for several patents. One of his articles is included in Spotlight on Optics by OSA in 2015. Also, he is included in Analysis of 2023 Stanford University’s Top 2% Scientists (Career Impact) (1960 - 2022) and Top 2% Scientists in 2021/2022.

Speech Title: Optimal Parameters for Selective Laser Melting in Additive Manufacturing for Green Design

Abstract: Optimizing Selective Laser Melting (SLM) parameters is crucial for enhancing the efficiency and precision of additive manufacturing for green design. This study focuses on refining process parameters for Ti6Al4V and IN718 using a dimensionless model, melting pool geometry model, energy-saving index, and maximum hatching space. The proposed optimization strategy effectively reduces energy consumption while increasing throughput, ensuring superior mechanical properties of the fabricated components.
Furthermore, processing maps for IN713LC and AA6061 were developed to characterize crack-free conditions in 3D printing. By defining optimal process windows based on specific criteria, these maps contribute to improving material performance and structural integrity. The integration of these findings enhances manufacturing reliability, making SLM more viable for industrial applications. This study provides valuable insights into energy-efficient and high-precision metal additive manufacturing.

Prof IR Lim is currently a registered professional engineer (RPE). He received a first degree from Universiti Teknologi Malaysia, a Master's Degree and PhD from National University of Singapore and Nanyang Technological University, respectively. Prior to joining CityU, he was a post-doctoral research fellow at Department of Civil Engineering, The University of Queensland and Department of Mechanical Engineering, The University of Hong Kong. Prof. Lim is also a visiting professor at various universities including the University of Western Sydney, Dalian University of Technology, etc. He has expertise in vibration of plate and shell structures, dynamics of smart piezoelectric structures, nanomechanics and symplectic elasticity. He is the Editor for Journal of Mechanics of Materials and Structures (JoMMS), Associate Editor (Asia-Pacific Region) for Journal of Vibration Engineering & Technologies (JVET), Associate Editor for International Journal of Bifurcation and Chaos (IJBC), International Subject Editor for Applied Mathematical Modelling (AMM), and also on the editorial board of some other international journals. He has published among one of the well-selling titles in Engineering Mechanics entitled "Symplectic Elasticity", co-authored with W.A. Yao and W.X. Zhong, as recorded in April 2010 by the publisher, World Scientific. He has published more than 300 international journal papers, accumulated more than 3000 independent citations, and one of the papers was granted the IJSS 2004-2008 most cited article award. He was also awarded Top Referees in 2009, Proceedings A, The Royal Society.

Speech Title: Polarization-dependent Elastic Wave Control by A Novel Honeycomb Topological Metamaterial

Abstract: Elastic wave manipulation by topological metamaterial has always been a hot research topic due to its great application potential. However, the rich polarization makes elastic wave more complicated than other waves and restricts the development of topological elastic metamaterial within mono-polarized waves. This paper introduces a frame structure in hexagonal lattice which can separately control the in-plane and out-of-plane polarized bandgap by utilizing the accidental Dirac cone. Further investigations reveals that the in-plane and out-of-plane accidental Dirac cone divide the parametric space into four regions, where each region has distinct valley Chern numbers. The combination of unitcells from different regions enable polarization-dependent topological protected interface modes, where some cases only support in-plane or out-of-plane mode while some cases support both. By employing such a peculiar property, this paper demonstrates polarization-dependent waveguiding and wave separation. One of the designed modes is manufactured by 3D printing and experiment validation of wave separation is conducted. Further study shows that the in-plane and out-of-plane waveguiding is independent of each other even if there are intersections on the waveguiding paths. Therefore, some interesting elastic devices which can carry and encrypt messages can be designed, and several examples are demonstrated. The presented work in this paper helps expand applications of topological elastic metamaterial from dealing with mono-polarized waves to both in-plane and out-of-plane polarized wave, which holds great potential in exploring more advanced elastic devices.