Research HighIights

Dr Weisong WEN, a research assistant professor in the Department of Aeronautical and Aviation Engineering (AAE) and a member of the Research Centre for Unmanned Autonomous Systems (RCUAS), has established a research collaboration with Meituan Inc. on the development of autonomous parcel delivery using unmanned aerial vehicles (UAVs) in urban environments. The collaboration, which is supervised by Dr WEN, involves AAE and the Meituan Academy of Robotics Shenzhen (MARS) and aims to develop reliable and safety-certifiable perception technology for UAVs operating in urban canyons.

The project will focus on vision-aided GNSS-RTK positioning for UAV systems in urban canyons. Dense urban canyons pose a challenging problem for UAV navigation, which has so far prevented the widespread deployment of UAV systems. However, Dr Guoquan HUANG, Associate Professor at the University of Delaware and the technical lead of Meituan UAV, believes that this research has the potential to improve the UAV's perception of safety and unlock a series of UAV applications in dense urban canyons.

Professor Chih-yung WEN, Head of AAE, commented on the department's collaboration with Meituan as one of the successful examples of knowledge transfer within the RCUAS.

The Aviation Research Consortium (ARC) has been established under the Department of Aeronautical and Aviation Engineering (AAE) at the University on June 10, 2022. The formation of ARC aligns with the University's strategic research areas and is focused on conducting comprehensive research and analysis on aviation-related issues, and exploring solutions to address key social, economic, and environmental challenges faced by the aviation industry.

The members of ARC conduct research in a wide range of aviation-related fields, including air transport operations, air traffic management, airline and airport operations management, air mobility, sustainable air transport systems, aviation safety and reliability, and human factors and ergonomics. The consortium aims to nurture aviation research talent and establish a strong academic hub for aviation research through internal and external collaborations. ARC also aims to develop impactful applied research in air transport operations and aviation engineering that addresses societal challenges, with the support of research grants.

The ultimate goal of ARC is to set up a dedicated research center, the Aviation Research Centre, with all the research achievements of the consortium as its foundation. Additionally, ARC aims to become an influential think tank in the Greater Bay Area for the aviation industry. It will provide public services in aviation-related programs with a focus on education, research, and training, and offer innovative solutions in aviation research to the industry and government bodies.

The consortium is currently collaborating with major players in the aviation industry including Cathay Pacific Airways, Hong Kong Airlines, Hong Kong Express Airways, and the Hong Kong Observatory. These collaborations indicate that the establishment of ARC comes at an opportune time, as the aviation industry is recovering from the impact of the COVID-19 pandemic.

The Hong Kong Polytechnic University (PolyU) is collaborating with the Academy of Aerospace Propulsion Technology (AAPT) to establish the Joint Research Centre of Advanced Aerospace Propulsion Technology. The signing ceremony was held on July 4, 2022.

The collaboration, led by PolyU's Department of Aeronautical and Aviation Engineering (AAE), is part of a five-year plan and includes various joint research and development projects. The focus of these projects will be on researching and developing key technologies related to aerospace propulsion, with the goal of enhancing engineering research and production capabilities in the field. Additionally, the partnership aims to cultivate a group of high-level interdisciplinary experts for future applications. This long-term, comprehensive partnership will support China's major technology projects.

The first phase of the collaboration includes four projects:

1. Research on Oblique Detonation Engine Technology (斜爆轟發動機技術研究)
2. Research on the Influence of Propellant Temperature on the Performance of Space Propulsion Engine (推進劑溫度對空間發動機性能影響機理研究)
3. Numerical Simulations of Combustion Flow Field of a Torch-Ignition Chamber (火炬點火室燃燒流場仿真計算研究)
4. Numerical Investigations of Flow Field Homogeneities in Injectors’ Chambers of a Hydrogen/Oxygen Engine (氫氧發動機噴注器頭腔流場均勻性仿真分析)

The Research Centre of Unmanned Autonomous Systems (RCUAS) was established at the Hong Kong Polytechnic University (PolyU) on May 12, 2022, with the goal of coordinating research and development efforts related to unmanned autonomous systems (UAS) across different departments, institutes, and centers within the university. The center aims to facilitate internal and external collaborations with leading partners and is expected to have an impact on research institutes such as the Institute for Sustainable Development (RISUD), Smart City Research Institute (SCRI), Research Institute for Artificial Intelligence and IoT (RIAIoT), and the Research Institute for Aging and Mobility (RIAM). The center will provide physical research and development platforms for UAS research and align with PolyU's motto, "to learn and to apply, for the benefit of mankind."

RCUAS also plays an important role by providing physical UAS research and development platforms to synergize the impactful researches conducted in PolyU. The ultimate goal is to collaboratively increase society-oriented research that will have a positive impact on Hong Kong, the Greater Bay Area, and the Asia-Pacific region.

Members of the RCUAS are involved in research projects with governmental departments and the industry, such as the Highways Department, the Innovation and Technology Commission (ITC), the Electrical and Mechanical Services Department (EMSD), the Environmental Protection Department (EPD), and Meituan and Huawei Technologies. The research achievements are aimed to alleviate the stress arising from the global trend of aging populations and facilitate the revolution arising from “Smart City” technologies.

Customized sports equipment has the potential to enhance athletic performance and prevent injury. In an recent interview, Professor ZHANG Ming, head of the Department of Biomedical Engineering at Hong Kong Polytechnic University, shared that his team has been studying the use of additive manufacturing technology (3D printing) to create customized foot orthotics.

According to Professor ZHANG, the current additive manufacturing technology is advanced, but the team is focusing on determining the optimal biomechanical design and printing parameters. Standardized insoles on the market today may not account for the unique characteristics and shapes of an individual's feet. By providing individually designed functional insole support, athletes and the general public can benefit from improved foot support and dynamic body alignment, leading to better footwear comfort and athletic performance.

The research team has been utilizing computational and experimental methods to study the biomechanics of footwear and orthotics, with a particular focus on understanding the interactions between different foot shapes and structures and different footwear designs and materials. In the next stage of the project, Professor ZHANG noted that the 3D-printed insole currently being developed only provides basic support. To support athletic performance, the insole will require additional optimization, such as multi-layers of support for moisture control, breathability, cushioning, rebound, and durability.

Edge computing is a new approach to delivering powerful computing capabilities at the edge of pervasive radio access networks, closer to users. A key research challenge in edge computing is to design an efficient offloading strategy for deciding which tasks should be processed by edge servers with limited resources. While many previous research efforts have aimed to tackle this challenge, they rely on centralized control, which is not practical as users are rational individuals with their own goals and interests.

This study presents a decentralized algorithm for computation offloading, allowing users to make independent offloading decisions. Game theory is used in the algorithm design, and the existence and uniqueness of equilibrium have been established. In contrast to existing research, this study addresses the challenge of users potentially refusing to share private information, such as network bandwidth or preferences, by designing a solution that can make offloading decisions without requiring private information sharing.

The offloading game is formulated as a multi-agent partially observable Markov decision process. An algorithm is proposed that utilizes a combination of policy gradient deep reinforcement learning and differential neural computing to solve this complex problem.

Fig. 1. The system architecture of the proposed approach

Fig. 2 Performance of the proposed approach as compared with Nash equilibrium

Dr Daniel LUO and his PhD students, Mr ZHOU Hao and Mr WU Shuohan, received the ACM SIGSOFT Distinguished Paper Award for their paper titled "NCScope: Hardware-Assisted Analyzer for Native Code in Android Apps." The award was presented at the 31st ACM SIGSOFT International Symposium on Software Testing and Analysis (ISSTA), which is a leading research symposium on software testing and analysis, and is considered a CCF-A conference. The paper was the result of a collaboration between researchers from Pennsylvania State University, Zhejiang University, Tsinghua University, and Washington State University.

The paper presents a novel hardware-assisted analyzer for native code in Android apps. The team leveraged ETM, a hardware feature of the ARM platform, and eBPF, a kernel component of the Android system, to collect real execution traces and relevant memory data of target apps. They also developed new methods to scrutinize the apps' native code based on the collected data. To showcase the unique capabilities of NCScope, the team applied it to four applications that could not be accomplished by existing work. These applications included a systematic study of self-protection and anti-analysis mechanisms implemented in the native code of apps, an analysis of memory corruption in native code, and the identification of performance differences between functions in native code.

The results revealed that only 26.8% of the analyzed financial apps implemented self-protection methods in native code, indicating that the security of financial apps is far from expected. Additionally, 78.3% of the malicious apps under analysis displayed anti-analysis behaviors, suggesting that NCScope is very useful in inspecting sophisticated mobile malware. Furthermore, NCScope was able to effectively detect bugs in native code and identify performance differences.

The miniaturization of biosensors has become increasingly important in recent years, with great potential for in vivo biomarker detection, disease diagnostics, and point-of-care testing during public health crises, such as the ongoing COVID-19 pandemic. In an effort to address this need, Professor Aping ZHANG and his team at the Department of Electrical Engineering have developed an ultraminiature optical fiber-tip plasmonic biosensor for label-free biodetection.

This biosensor is based on plasmonic gold nanoparticles (AuNPs) that are directly printed on the end face of a standard multimode optical fiber in the visible light range. The team developed an in-situ precision photoreduction technique to additively print micropatterns of size-controlled AuNPs. These AuNPs exhibit distinct localized surface plasmon resonance, the peak wavelength of which provides an ideal spectral signal for label-free biodetection.

The resulting optical fiber-tip plasmonic biosensor can detect not only antibodies, but also the SARS-CoV-2 mimetic DNA sequence at a concentration level of 0.8 pM. This ultraminiature fiber-tip plasmonic biosensor provides a cost-effective biodetection technology with a wide range of applications, from point-of-care testing to in vivo diagnosis of stubborn diseases.

The research results have been published in the highly-renowned journal Biosensors and Bioelectronics (IF: 12.54), showcasing the innovative and impactful nature of the work conducted by Professor ZHANG and his team.

Hearing loss is a rapidly growing global health issue that affects people of all ages. According to the World Health Organization, an estimated 1.5 billion people, or one in five people, currently suffer from hearing loss, with that number projected to rise to 2.5 billion by 2050. Hearing loss can have a significant impact on speech recognition and cognitive development, and is also associated with an increased risk of dementia. For individuals with severe to profound hearing loss, cochlear implantation is the only treatment option.

Cochlear implantation is an extremely delicate surgical procedure that involves the precise positioning of a cochlear implant (CI) to stimulate the auditory nerve and restore hearing in deaf patients. However, current approaches to cochlear implantation have several limitations, including a lack of visualization of intracochlear structures during the procedure and a lack of feedback on insertion forces.

In an effort to address these issues, Professor Hwa-Yaw TAM and his research team, in collaboration with the University of Melbourne and the Royal Victorian Eye and Ear Hospital [Fig.1], have developed a smart cochlear implant integrated with a novel type of ZEONEX-based polymeric optical fiber sensors. The sensors were designed and fabricated using PolyU’s in-house fiber drawing facility, and they are able to provide real-time feedback to surgeons when navigating the implant during the procedure. The smart CI is designed to minimize insertion trauma, promoting hearing preservation.

Trials using the sensors have already been carried out on CIs integrated with PolyU’s single core polymeric FBGs inside cochlear phantoms [Fig.2], allowing for detection of contact forces in the scale of millinewtons. The industrial and clinical experience of the researchers involved in the project has paved the way for the clinical translation of these research outcomes, ensuring that the new diagnostic approaches will truly benefit individuals with hearing impairment.

A joint patent between PolyU and the University of Melbourne has been filed, and the University of Melbourne is in discussion with Cochlear Ltd, the largest cochlear implant company in the world, regarding the use of this technology in their products. Cochlear Ltd. annual sales of about HK$ 8.7 billion.

For more information: https://www.sciencedirect.com/science/article/pii/S095656632200906X

Fig. 1. Professor Tam’s team and his collaborators at University of Melbourne, lead by Professor Stephen O’Leary, Head of Department of Otolaryngology.

Fig. 2 Smart cochlear implant with embedded optical polymeric fibre sensors for contact force measurement and trajectory identification, inserted inside a cochlear phantom.

The State Key Laboratory of Ultra-precision Machining Technology (SKL-UPMT) at The Hong Kong Polytechnic University has partnered with the School of Optometry and Vision Science and Technology Co. Ltd. (VST), a start-up supported by PolyU, to develop a new type of spectacle lens for controlling the progression of myopia, or short-sightedness.

The Nano Multi-ring Defocus Incorporated Spectacle Lens has been developed using the Ultra-precision Nano Multi-rings Machining Technology, a patented technology that combines advanced optics design, ultra-precision machining, precision measurement, and precision moulding technology. The research team has successfully applied Defocus Incorporated Soft Contact (DISC) technology, which is typically used for contact lenses, to the production of spectacle lenses.

The new spectacle lens offers added comfort for wearers and more stable vision. Its non-invasive design also makes it more suitable for children of different ages.

Professor Benny CHEUNG, Professor of the Department of Industrial and Systems Engineering and Director of SKL-UPMT at PolyU, said, “We are delighted to extend the locally developed Ultra-precision Nano Multi-rings Machining Technology to fine-tune and manufacture optometric products. We will continue to create new technologies and solutions for diverse industries to benefit society.”

Collaboration leads to success: From left to right, representatives from State Key Laboratory of Ultra-precision Machining Technology (SKL-UPMT), Vision Science and Technology Co. Ltd. (VST) and School of Optometry at The Hong Kong Polytechnic University (PolyU) pose with their revolutionary Nano Multi-ring Defocus Incorporated Lens for myopia progression control.

The Ultra-precision Nano Multi-ring Machining Technology developed by SKL-UPMT at PolyU combines advanced optics, ultra-precision machining and precision measurement to create cutting-edge optometric solutions.