Prof. Zheng Hong (George) Zhu, H-index: 40 (Scopus)

York University, Canada

MRSC, FCAE, FEIC, MIAA, AFAIAA, FCSME, FASME, SMIEEE, MAAS

Zheng Hong Zhu (Senior Member, IEEE) received the B.Eng., M.Eng., and Ph.D. degrees in engineering mechanics from Shanghai Jiao Tong University, Shanghai, China, in 1983, 1986, and 1989, respectively, the M.A.Sc. degree in robot control from the University of Waterloo, Waterloo, ON, Canada, in 1998, and the Ph.D. degree in mechanical engineering from the University of Toronto, Toronto, ON, in 2004.,He is currently a Professor and Tier I York Research Chair in Space Technology with the Department of Mechanical Engineering, York University, Toronto. He has authored and coauthored more than 250 articles. His research interests include dynamics and control of tethered space systems and visual servo space robotics.,Dr. Zhu is a Member of the College of the Royal Society of Canada and a licensed Professional Engineer. He is a Fellow with the Engineering Institute of Canada, the Canadian Society for Mechanical Engineering, and the American Society of Mechanical Engineers, and an Associate Fellow with the American Institute of Aeronautics and Astronautics. 

Speech Title: Exploring Effects of Microgravity on FDM-Based Additive Manufacturing in Space.

Abstract: Additive manufacturing (AM) in space overcomes launch vehicle limitations of space and weight, expanding the feasible domain of space structure design. Space AM involves melting and forming materials in microgravity, where controlling liquid and powder materials is challenging. Consequently, Fused Deposition Modelling (FDM), which uses filament materials, is currently the primary technology for space AM. Factors such as surface tension, gravity, and atmospheric pressure in FDM influence layer deposition, affect the dimensional precision and mechanical properties of printed structures.  

This study conducted experimental investigation on the effect of gravity on interlayer fusion and mechanical properties. The gravity effect on the AM make structures are simulated by printing specimens at angles ranging from 0° to 90° relative to the gravity direction in 15° intervals. Here, 0° simulates zero gravity (gravity parallel to the deposition layer interface), while 90° represents Earth-like gravity effects. All specimens were printed with a 90° raster pattern. Tensile and compressive specimens were manufactured and tested at constant strain rates of 5 mm/min and 1.3 mm/min, respectively. Mechanical properties such as Young’s modulus, ultimate strength, yield strength, and fracture stress and strain were derived from stress-strain curves. Tensile tests showed a decline in ultimate tensile strength, fracture stress, and fracture strain as the print orientation increased from 0° to 75°, with a recovery at 90°, possibly due to a change in failure mode. Compression tests indicated significant improvements in mechanical properties at higher print orientations, particularly between 0° and 15°. Fracture and densification strains remained stable across orientations, indicating consistent ductility. Dimensional analysis revealed that higher print orientations led to smaller tensile specimen dimensions and slight reductions in compression specimen diameters, underscoring gravity's influence on dimensional accuracy. The findings suggest that while zero-gravity conditions weaken interlayer bonds, microgravity has a lesser impact on material strength compared to Earth-bound conditions. These insights are valuable for optimizing polymer 3D printing techniques for in-space additive manufacturing.

Prof. Yaolong Liu, Zhejiang University, China

Yaolong Liu, researcher of Zhejiang University's Hundred Talents Plan, doctoral supervisor, member of the working committee of the Ministry of Education's Virtual Teaching and Research Office of Air Vehicle Design and Engineering, member of the Aerospace Special Committee of Virtual Simulation Experimental Teaching and Learning Innovation Alliance, and expert of doctoral dissertation evaluation of the Academic Degree Centre of the Ministry of Education. His main research interests include the overall design methodology and software of aircraft, the design and verification of new concept new energy vehicles, etc. He has published more than 20 papers in Progress in Aerospace Sciences and other important aerospace journals and conferences, and has also published a monograph in English, co-edited a book in English, and co-edited a textbook. He has served as a member of the editorial board of several international journals, a guest editor, and the chairman of several international aerospace conferences. He has been invited to give presentations at the COMAC Masters' Forum, the 20th National Conference on Computational Fluid Dynamics, and the Aeronautical Society of China (ASOC) 2023 Binzhou Aerospace and Aeronautics Innovation Forum.

Speech Title: Towards Green Aviation: Status and Challenges of New Technologies in Aircraft, Propulsion, and Operations.

Abstract: The annual aviation carbon emission is about 900 million tons.To reduce the carbon emission of aviation, a lot of research on new aircraft airframe technologies, energy systems and operations has been carried out. This report includes the following aspects: 1. To sort out the work of adopting new energy systems for aviation emission reduction; 2. To summarize the current status of new energy systems represented by electric propulsion, hydrogen combustion and hydrogen fuel cell; 3. To analyze the feasibility of new energy systems for emission reduction of existing and future aircraft; 4. To propose possible future development directions and research needs of new energy systems for aviation in view of the scientific problems and technical challenges involved.

Assoc. Prof. Huang Weimin, H-index: 55 (Scopus)

School of Mechanical & Aerospace Engineering, Nanyang Technological University, Singapore

Dr. Wei Min Huang is currently an Associate Professor at the School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore. He has 17 years of experience on shape memory materials (alloy, polymer, composite and hybrid) and technologies. He has published two books (Thin Film Shape Memory Alloys [co-ed., Cambridge University Press, 2009]; Polyurethane Shape Memory Polymer [co-au., CRC, 2011]) and over 100 papers in journals, such as Materials Today, Soft Matter, Journal of Materials Chemistry etc,  and has been invited to review manuscripts from over 60 international journals and proposals from American Chemical Society etc. He is currently on the editorial board of four journals.

Speech Title: Rapid manufacturing anywhere, anytime.

Abstract: Rapid manufacturing on space/air/sea/land missions, where either gravitational force is missing or severe random disturbance may present continuously, is highly in demand. However, till today, there is no reliable technique for such working environments. The purpose of this study is to develop a technology for rapid 3D printing in the solid state of polymeric materials to get rid of the problems in harsh working environments.

The basic concept is via UV cross-link polymeric materials in the solid state for rapid volumetric additive manufacturing. However, the uncross-linked parts must be easily removed in a convenient manner, i.e., by heating or cooling for melting, or washing away by solvents or even by water. In addition, excellent shape memory effect (SME) of the cross-linked polymers is required to ensure high accuracy of the printed items.

Proof-of-the-concept has been done using a thermal gel, UV cross-linkable vitrimer and dual cross-linkable resin.