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PolyU builds advanced human-robot collaboration system, empowering high-end manufacturing tasks

With human-robot collaboration at the core of Industry 5.0, a research team at The Hong Kong Polytechnic University (PolyU) has made significant progress in this field, developing a new generation of “human-machine symbiotic” collaborative manufacturing systems. In addition to perceiving complex environments in real time and accurately interpreting operators’ intentions, the system can achieve skill transfer and self-learning via simple demonstration, while carrying out autonomous process code generation and automatic adjustment for highly accurate task execution. It has been successfully applied to high-end manufacturing tasks such as autonomous drilling on large aircraft and the disassembly of electric vehicle batteries, laying a solid foundation for a new model of human-centric smart manufacturing. The goal of human-robot synergy is to combine the adaptability and responsiveness of humans with the precision and stability of machines. Led by Prof. ZHENG Pai, Endowed Young Scholar in Smart Robotics and Associate Professor of the PolyU Department of Industrial and Systems Engineering, the research team has developed the “Mutual Cognitive Human-Robot Collaboration Manufacturing System” (MC-HRCMS). With a shift away from pre-programmed operations, this system is centred upon holistic scene perception—by collecting and analysing multimodal sensing data including vision, haptics, language and physiological signals, it enables highly accurate and comprehensive environmental analysis, while carrying out autonomous decision-making and flexible task execution. The system features advanced machine learning and 3D scene perception capabilities that deliver efficiency and safety, greatly enhancing fluid human-robot interaction in complex manufacturing scenarios. Through industry collaboration projects, the team has tailored human-robot collaboration systems for multiple leading enterprises and successfully deployed them across various scenarios that involve precision and/or complex work procedures. Prof. Zheng said, “The global manufacturing industry is shifting towards a human-machine symbiotic paradigm that emphasises more flexible automation. Our research aims to develop a paradigm that offers multimodal natural perception, cross-scenario skill transfer and domain foundation-model autonomous execution, so that robots are no longer just tools, but intelligent agents that can evolve with human operators. This provides smart factories with a new path beyond pre-programmed automation.” Semi-structured and unstructured production scenarios, such as personalised manufacturing, often involve large-scale, complex assembly, disassembly and inspection processes that demand high cognition and rapid adaptation. In this regard, the team introduced a “novel vision-language-guided” planning framework that combines Large Language Models (LLMs), Deep Reinforcement Learning (DRL), and Mixed-Reality Head-Mounted Displays (MR-HMD), enhancing the ability to execute personalised and other unpredictable production tasks. A key innovation of the framework is the combination of a vision-language-guided target object segmentation model with language-command-driven task planning, allowing the system to integrate visual information with language-based instructions. This enables robots to comprehend complex task semantics, interpret dynamic scenes and collaborate efficiently with human operators. In particular, the head-mounted device enables real-time data acquisition and provides immediate, intuitive guidance to operators, redefining the human-machine interaction interface. Prof. Zheng said, “The future of smart manufacturing is not about machines getting smarter to replace humans, but about creating systems where humans and robots learn, adapt and succeed together to achieve higher productivity and flexibility. To meet this need, the next-generation robot manipulators should be capable of continual learning and optimisation under human guidance, enabling efficient and natural human-robot interaction.” To further advance human-robot collaboration, Prof. Zheng will also lead his team in exploring self-configurable human-robot networks, skill transfer mechanisms and autonomous multi-agent task execution. By building a deeply human-centric intelligent manufacturing system and expanding it into more key domains, the team strives to guide society towards a technology-empowered, empathetic and human-oriented smart era. With his dedication to researching “human-machine symbiotic” collaborative manufacturing systems, Prof. Zheng was awarded funding from the Excellent Young Scientists Fund by the National Natural Science Foundation of China in 2024. He now leads the RAIDS research team on the above projects. For more details, please visit: https://www.raids.group/ 

PolyU and RGC jointly hosted the RGC Research Summit, spearheading the Research and Innovation in Hong Kong

PolyU is proud and honoured to join hands with Research Grants Council (RGC) and the University Grants Committee (UGC) to co-host the RGC Research Summit on 11 December at Hong Kong Science Park. Celebrating the RGC 35th Anniversary with the theme “Forging Frontiers: Shaping the Future of Knowledge and Discovery”, this landmark event gathered over 700 leading researchers, academics and industry experts from Hong Kong and around the world, fostering dialogue on impact research and global collaboration.  We were privileged to have Dr Choi Yuk-lin, the Secretary for Education, HKSAR Government, as our Guest of Honour, who highlighted Hong Kong’s readiness to become a strategic hub for innovation, backed by a strong research track record and commitment to nurturing emerging talent. PolyU was honoured to feature an exceptional line-up of distinguished keynote speakers from home to aboard for this full-day programme, sharing insights that underscored Hong Kong’s potential as a global innovation hub driven by interdisciplinary collaboration and fresh research perspectives. The summit also featured the Presidents’ Roundtable session, bringing together leaders from all eight UGC-funded universities to explore Hong Kong’s role in shaping the future of research. PolyU President Prof. Jin-Guang Teng joined as one of the panellists.  Prof. Christopher Chao, Senior Vice President (Research and Innovation) and Prof. Hongxia Yang, Associate Dean (Global Engagement) of the Faculty of Computing and Mathematical Sciences, and Executive Director of the PolyU Academy for Artificial Intelligence, contributed to the summit as the speakers of thematic session. They shared valuable insights on global collaboration, particularly between the Chinese Mainland and beyond, as well as research trends and impact. To encourage forward-thinking dialogues, the summit’s breakout sessions also brought together top academics from seven countries, including China, the US, the UK, Singapore, the UAE, and Switzerland. PolyU remains committed to advancing knowledge, driving innovation, and fostering global partnerships to address pressing challenges and create a better future for society.

PolyU develops ultra-stable, mucus-inspired hydrogel to boost gastrointestinal wound healing

The Hong Kong Polytechnic University (PolyU) has developed an acid-resistant “ultra-stable mucus-inspired hydrogel” (UMIH), marking a breakthrough in the field of gastrointestinal medicine. Traditional hydrogels—gelatin-like materials that absorb and retain water—are widely used to aid wound healing and extend drug release. However, they usually break down in acidic environments like the stomach. Inspired by the natural properties of gastric mucus, a PolyU research team has developed UMIH, a hydrogel that adheres 15 times more strongly than conventional gastric mucosal protectants, showing considerable potential for wound repair and targeted drug delivery and promising large‑scale commercialisation. The research was carried out by the PolyU team in collaboration with researchers and clinicians from Sichuan University. The research showed that UMIH significantly improved gastrointestinal wound healing in animals and outperformed a clinically approved mucosal protectant used to protect the stomach lining. The study, “Mucus-inspired hydrogels with protonation-driven adhesion for extreme acidic conditions,” has been published in Cell Reports Physical Science. Prof. WANG Zuankai, Associate Vice President (Research), Dean of the Graduate School, Kuok Group Professor in Nature-Inspired Engineering, Chair Professor of the Department of Mechanical Engineering, Director of Research Center for Nature-Inspired Science and Engineering at PolyU, who led the study, said, “UMIH shows promise in treating gastroesophageal reflux and gastric ulcers, and in protecting post-surgical wounds. It can also be combined with endoscopic drug delivery for minimally invasive therapy. This research establishes UMIH as a transformative, extremely acid-tolerant platform, with immediate applications in gastrointestinal repair and targeted drug delivery, while also opening avenues for next-generation implantable devices to accelerate translation to the clinic.” Prof. Wang explained that aluminium phosphate gel (APG)—a clinically approved mucosal protectant and antacid—has long been used to treat gastric ulcers and gastro‑oesophageal reflux. The experimental data show that, under simulated gastric conditions (pH 2), UMIH achieved a wet adhesion strength of 64.7 kilopascals (kPa), 15-fold higher than APG; APG fully degraded after three days, whereas UMIH retained about 50% of its structural integrity after seven days. In vitro tests on cultured gastrointestinal cells found no signs of toxicity, while UMIH also inhibited the growth of Escherichia coli and Staphylococcus aureus, indicating antibacterial potential. Like conventional hydrogels, UMIH consists of a meshwork of polymers that absorb water to create a strong but jelly-like consistency. To enhance its acid resistance, the research team integrated three key molecular components into UMIH’s structure: ELR-IK24, a protein that binds hydrogen ions under acidic conditions to reduce local acidity; tannic acid, which boosts adhesion of hydrogel; and HDI, a molecule that stabilises the hydrogel’s structure under acidic conditions. “Our hydrogel is a synergistic combination of three essential molecular components. This multi-crosslinking architecture keeps UMIH firmly intact in strong acid while maintaining softness and injectability—qualities well suited to clinical use,” said Ms Yeung Yeung CHAU, a Research Associate of the PolyU Department of Mechanical Engineering and a member of the research team. “We tested UMIH in pig and rat models of esophageal injury. Compared with control animals and APG‑treated animals, UMIH adhered more firmly to wound faces and improved healing. UMIH reduced  tissue damage and inflammation and promoted the growth of new blood vessels, which is essential for healing,” explained Dr Xiao YANG, a Postdoctoral Fellow of the PolyU Department of Mechanical Engineering and a member of the research team. While clinical trials will be needed to validate UMIH’s safety and efficacy in humans, it holds strong potential for commercialisation. It is low-cost, easy to mass-produce and developed from components with established safety profiles. The material is ready to use both in operating room and on the production line. Looking ahead, the research team plans to integrate UMIH with drug release systems and implantable flexible electronics to create smart gastrointestinal devices capable of real-time treatment and monitoring.

PolyU hosts Quantum HK 2025, convening global experts to probe frontier advances in quantum technologies

As a pivotal hub fostering international research collaboration between the Greater Bay Area and the rest of the world, Hong Kong serves as a unique intermediary in driving the innovation and translation of quantum technologies. The “International Conference on Quantum Technology 2025” (Quantum HK 2025), hosted by The Hong Kong Polytechnic University (PolyU), has recently concluded, having attracted more than 200 experts, scholars, researchers and industry leaders. The Conference fostered in-depth discussion on cutting-edge breakthroughs and future developments in quantum technologies, further expanding the breadth and depth of academic exchange and academia-industry collaboration. The event’s co-organisers were The University of Hong Kong (HKU), The Chinese University of Hong Kong (CUHK), The Hong Kong University of Science and Technology, City University of Hong Kong (CityUHK), the Physical Society of Hong Kong, and the Beijing-Hong Kong Academic Exchange Centre. Prof. Christopher CHAO, PolyU Senior Vice President (Research and Innovation) remarked, “As this year marks the International Year of Quantum Science and Technology, quantum technologies have become a key agenda item of global interest. Over the past year, breakthroughs in quantum computer, quantum communication and quantum metrology have laid important foundations for the application of artificial intelligence and secure communications. PolyU has successfully established Hong Kong’s first quantum chip-based communication network, completing a quantum encrypted transmission test that spanned a 55km-long optical fibre network—demonstrating Hong Kong’s leadership in quantum innovation. Looking ahead, PolyU will continue to nurture talent, foster interdisciplinary collaboration and accelerate the translation of quantum technology scientific achievements into societal applications, contributing to global quantum development.” Prof. Ai-Qun LIU, the Conference Co-Chairman, Director of the Research Institute for Quantum Technology, Chair Professor of the Department of Electrical and Electronic Engineering, and Hong Kong Global STEM Scholar, noted, “This conference gathered experts bringing insights from academia and industry, building an interdisciplinary platform for exchange and collaboration in quantum technologies. Moving forward, it will continue to unite diverse stakeholders to expedite research translation and industrialisation, injecting new momentum into the development of quantum technologies in Hong Kong, the Greater Bay Area and the Nation.” The Conference was co-chaired by Prof. Ai-Qun Liu, Prof. Oscar DAHLSTEN and Prof. Din-Ping CAI from CityUHK, as well as Prof. Giulio CHIRIBELLA from HKU. There were also multiple keynote talks aimed at facilitating in-depth discussions on quantum computing, quantum information security and metrology. The speakers included: Academician Dapeng YU from the Shenzhen Institute for Quantum Science and Engineering; Prof. Xicheng ZHANG from the University of Rochester; Prof. Guilu LONG from Tsinghua University; Prof. Leong Chuan KWEK from Nanyang Technological University; Prof. Abolfazl BAYAT from the University of Electronic Science and Technology of China; Prof. Tim BYRNES from NYU Shanghai; Prof. Yanoar P. SARWONO from the Agency for Science, Technology and Research, Singapore; Prof. Qi ZHAO from HKU; and Prof. Haidong YUAN from CUHK. Meanwhile, representatives from other leading organisations and companies—including Huawei, QBosoN, SpinQ, Tencent Quantum Lab and Xuntai Quantum Technology—engaged in roundtable discussions, focusing on industrialisation of research outcomes. They also offered forward-looking recommendations on standardisation, modularisation and scalability in quantum technologies, while also emphasising the need to accelerate the development of a stable and multi-tier talent pipeline to effectively support innovation and growth in the quantum industry.

PolyU secures funding for five projects in Germany/Hong Kong Joint Research Scheme 2025/26

The Hong Kong Polytechnic University (PolyU) is committed to cultivating a world-class academic environment and enhancing international research collaboration. Demonstrating the University’s research excellence and global vision, five PolyU projects have been awarded funding under the Germany/Hong Kong Joint Research Scheme 2025/26. Led by scholars from the Faculty of Business,  Faculty of Construction and Environment, and Faculty of Engineering, the awarded projects span diverse fields, reflecting PolyU’s strength in interdisciplinary research and its commitment to tackling global challenges.  The awarded projects include advancements in mechanism design for urban air mobility operators, exploration of cointercalation chemistry in next-generation energy storage technologies, reassessment of entrepreneurial narratives through podcasts, improvements in parking space efficiency in dense urban environments, and the development of solar-driven carbon‑neutral technologies to convert food waste into value‑added products.  The five PolyU-awarded projects: Principal Investigator Project Title Awarded Amount Prof. Ang LI Assistant Professor of the Department of Aeronautical and Aviation Engineering Mechanism Design and Resource Allocation under Strategic Behavior of Urban Air Mobility (UAM) Operators HK$89,600 Prof. XU Zhenglong Associate Professor of the Department of Industrial and Systems Engineering Decipher cointercalation chemistry of graphite anodes in post-lithium ion batteries HK$89,600 Prof. Amy OU Yi Associate Professor of the Department of Management and Marketing The Humble Founder? Rethinking Entrepreneurial Narratives Through Podcasts HK$44,800 Prof. Sunghoon JANG Assistant Professor of the Department of Civil and Environmental Engineering (PACE) Parking Space Efficiency: Making the Most of Urban Space through Shared Use HK$82,400 Prof. Ren Jingzheng Associate Professor of the Department of Industrial and Systems Engineering Converting food waste into value-added products in Germany and Hong Kong: Solar-driven carbon-neutral technology development, feasibility analysis, and policy implications HK$89,600   Collectively, these initiatives highlight PolyU’s role as a bridge between Hong Kong and international partners in addressing sustainability, innovation, and societal transformation. The Research Grants Council (RGC) and the German Academic Exchange Service (DAAD) have collaborated since 1996 to promote research collaboration between Hong Kong and Germany by providing researchers in both locations with travel grants ranging from one to two years.

PolyU Hosts Its First Technology Achievement Transformation Conference

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Media interview: PolyU’s HEROCARE eases anxiety and enhances care in paediatric cancer treatment

In the RTHK TV programme "MagaSenior," Prof. Helen Law Ka Wai, Associate Head and Associate Professor at the Department of Health Technology and Informatics (HTI), and Dr Vincent Leung Wan Shun, Associate Professor of Practice at HTI at The Hong Kong Polytechnic University (PolyU), shared insights about the HEROCARE programme, which improves the experiences of paediatric cancer patients undergoing radiotherapy. The HEROCARE programme utilises the Hybrid Immersive Virtual Environment (HiVE) at PolyU to create positive experiences for both patients and caregivers, helping reduce fear and anxiety during treatment. Through personalised sessions and on-site hospital support, the programme enhances radiotherapy preparation and supports the physical and emotional well-being of its participants. Prof. Law highlighted that the success of the HEROCARE programme extends beyond reducing reliance on anaesthesia. It also combines compassionate learning with clinical service, providing valuable practical experience for future radiographers. The initiative aims to establish itself as the standard service model for paediatric radiotherapy in Hong Kong, garnering broad support from hospitals, experts, and the academic community. HEROCARE was developed during the challenging circumstances of the COVID-19 pandemic when caregivers and social workers faced restriction in accessing hospital areas. By leveraging PolyU’s research facilities and expertise, the research team successfully developed this innovative initiative to support the clinical preparation for paediatric patients.  

PolyU establishes Academy for Artificial Intelligence to develop a world-class AI innovation hub

The Hong Kong Polytechnic University (PolyU) today held the PolyU Academy for Artificial Intelligence (PAAI) Inauguration, demonstrating its support to the Nation’s “Artificial Intelligence (AI) Plus” initiative under the 15th Five-Year Plan to support high-quality development across industries. Leveraging PolyU’s cross-disciplinary strengths in computer science, mathematics and data science, the PAAI strives to foster international collaboration and help position Hong Kong and the Greater Bay Area as a globally influential AI innovation hub. On the same day, PolyU hosted a series of forums, bringing together experts from around the world to advance cutting-edge AI technologies and their innovative applications in healthcare. The Inauguration took place at the PolyU Chiang Chen Studio Theatre, officiated by Prof. SUN Dong, Secretary for Innovation, Technology and Industry of the HKSAR Government of the People’s Republic of China, and Prof. Jin-Guang TENG, President of PolyU. Prof. Sun Dong remarked, “The country’s Recommendations for Formulating the 15th Five-Year Plan reaffirm Hong Kong’s strategic position as the international innovation and technology centre. Our vision to become a global hub for AI development was underscored in the 2025 Policy Address delivered by our Chief Executive, with promotion of AI being top of our agenda, taken forward through multi-pronged measures on key enablers, including talent, data and industry applications.” “The inauguration of the PAAI marks not just a milestone, but a new chapter in our city’s united efforts to expedite the AI development. This Academy will inspire ideas, foster collaboration and fuel Hong Kong's AI ecosystem,” he added. Prof. Jin-Guang Teng elaborated: “Leveraging PolyU’s strong foundation in AI, computer science, mathematics, data science and other globally recognised disciplines, the PAAI will foster interdisciplinary and international collaboration to drive AI development, positioning Hong Kong and the Greater Bay Area as a leading AI innovation hub. It will deliver sustainable, efficient and impactful solutions for key sectors – ranging from healthcare and finance to education and beyond. It will also cultivate a talent ecosystem that can drive future innovation by leveraging Hong Kong’s international research environment and its government-industry-academia-research network.” Prof. Qiang YANG, PAAI Director, and Prof. Hongxia YANG, PAAI Executive Director, delivered keynotes on “The AI Revolution: Challenges and Opportunities” and “Co-Generative AI (Co‑GenAI)” respectively, elaborating on the University’s key tasks in advancing AI and how related projects are being translated into real-world applications that benefit diverse industries. Addressing future AI challenges, Prof. Qiang Yang noted that the PAAI will continue to advance key technologies including Co‑GenAI, Federated Learning and Edge Foundation Models, while setting out robust technological roadmaps in the priority fields of healthcare, education, finance and robotics. He highlighted Hong Kong’s dual positioning as an international financial centre as well as an international innovation and technology hub. Together with the extensive clinical networks and strong industry demand in the Guangdong-Hong Kong-Macao Greater Bay Area, the PAAI will seek to expand decentralised AI infrastructure, enabling more institutions to use advanced AI technologies under safe and controllable conditions. Prof. Hongxia Yang added that traditional AI training faces hurdles such as high thresholds for computing capacity and data privacy protection. By aggregating the strengths of hundreds of industry-specific models, Co‑GenAI can reduce reliance on centralised computing resources and build high-quality foundation models that better reflect real-world application scenarios. The PAAI is working with various medical institutions to implement the “Cancer GenAI” project, while also exploring the potential of AI in infectious disease prevention and control, robotic systems and finance. In the “International Forum on AI 2025”, moderated by Prof. Qiang Yang and the “Intelligent Oncology Forum” moderated by Prof. Jing CAI, Head of the PolyU Department of Health Technology and Informatics, convened leading experts from academia and clinical medicine. Participants engaged in in-depth discussions on the deep integration of AI and healthcare, innovative applications and cross-disciplinary technological breakthroughs, contributing insights to further propel AI technologies. The PAAI will contribute to building Hong Kong into a global testing ground that drives AI innovation in healthcare and smart city development, fostering world-class technologies and talent. It will also strengthen collaboration with industry, medical institutions, schools and government departments to apply AI solutions in public health and education systems. In ShanghaiRanking’s Global Ranking of Academic Subjects announced last month, PolyU ranked first in Hong Kong and 16th worldwide in the newly introduced “Artificial Intelligence” subject area, underscoring the University’s forward-looking strategy and achievements in facilitating AI in education. Officiating the PAAI Inauguration, Prof. Sun Dong, Secretary for Innovation, Technology and Industry of the HKSAR Government of the People's Republic of China, said that the PAAI marked not just a milestone, but a new chapter in the city’s united efforts to expedite the AI development. PolyU President Prof. Jin-Guang Teng said that the PAAI would cultivate a talent ecosystem to drive future innovation by leveraging Hong Kong’s international research environment and its government-industry-academia-research network. During the media interview session, PolyU Senior Vice President (Research and Innovation) Prof. Christopher Chao (2nd from left); PAAI Director Prof. Qiang Yang (2nd from right); PAAI Executive Director Prof. Hongxia YANG (1st from left); and Prof. Jing Cai, Head of the Department of Health Technology and Informatics (1st from right), outlined the PAAI’s strategy and the development and applications of AI across industries.

PolyU distinguished scholar Prof. Yang Chai receives Croucher Senior Research Fellowship 2026 for revolutionising AI computation

Prof. Yang CHAI, Associate Dean (Research) of the Faculty of Science and Chair Professor of Semiconductor Physics at The Hong Kong Polytechnic University (PolyU), has been awarded the prestigious Croucher Senior Research Fellowship 2026 in recognition of his outstanding achievements in revolutionising artificial intelligence (AI) computation at the sensor level. Each recipient of the Senior Research Fellowship receives funding up to HK$3 million to support their research. Prof. Christopher CHAO, Senior Vice President (Research and Innovation) of PolyU, congratulated Prof. Chai on this prestigious honour, “PolyU scholars are dedicated to world-leading research and innovation. This award not only recognises Prof. Chai’s pioneering work but also highlights PolyU research excellence in the field of AI computing. As an innovative world-class university, PolyU will continue to pursue excellence in education, research and knowledge transfer for the benefit of Hong Kong, the Nation and the world.” Prof. Chai’s research focuses on bioinspired computing and semiconductor devices. He has pioneered a disruptive in-sensor computing paradigm that revolutionises AI computation at the sensor level and has actualised this paradigm through hardware implementation for vision sensors. His innovative research on sensory AI contributes to the advancement in machine visions with enhanced image recognition, visual adaptation in extremely dim or bright lighting, and agile perception of dynamic motion. Expressing his gratitude for the award, Prof. Chai said, “I am deeply grateful to the Croucher Foundation for recognising my research in bioinspired computing and semiconductor devices. This award is not only an encouragement for me personally, but also a recognition of the PolyU research team. We will continue to pursue innovative research to create a positive impact on society.” Prof. Chai is a distinguished academic in the field of nanoelectronic devices and emerging computation paradigms. He earned his Bachelor’s degree at Nanjing University and his Master’s at Peking University, completing his PhD at The Hong Kong University of Science and Technology. His research on in-sensor motion perception was selected as one of the “China Chip10 Sciences”. He also received the 2024 Falling Walls Science Breakthrough in Engineering & Technology, funding from the National Science Fund of China for Distinguished Young Scholars, as well as the BOCHK Science and Technology Innovation Prize in the field of AI and Robotics.

A New Paradigm for Account-Based Blockchains

As financial technology matures and cryptocurrencies become increasingly popular, the security of blockchains used to process these transactions has emerged as a significant concern. Prof. Allen Men Ho AU, Associate Head (Research and Development) and Professor of the Department of Computing at The Hong Kong Polytechnic University, has introduced the Regulatable Privacy-Preserving Smart Contracts (RPSC), a smart contract system that effectively balances privacy with public transparency. RPSC’s compatibility has been demonstrated on Ethereum smart contract.  Smart contracts have become the backbone of decentralised finance, enabling automated transactions and the development of complex applications on blockchain platforms. As the technological foundation of Web3.0, smart contracts are increasingly relied upon to facilitate a wide range of financial and governance activities.    However, the transparency that makes blockchain technology so powerful also introduces significant privacy challenges. Every transaction and contract execution are recorded on a public ledger, exposing sensitive user data and transactional details to anyone with access to the network.    The tension between privacy and regulation has emerged as a central issue in blockchain research. Early privacy-preserving solutions, such as Zerocash and Hawk, leveraged advanced cryptographic techniques to anonymise transactions and user identities. These approaches, while effective in protecting privacy, often lacked the flexibility to selectively reveal private data when required for regulatory compliance or dispute resolution.    Ethereum, with its account-based structure, has become the dominant platform for smart contracts, hosting the majority of decentralised applications and managing billions in transaction value annually. Yet, the absence of robust privacy solutions tailored to account-based blockchains has left a critical gap in the ecosystem.   Led by Prof. AU, his research team has introduced RPSC system, a novel framework that combines fine-grained privacy controls, regulatory traceability and full compatibility with account-based blockchains, to address the above-mentioned problems.   The design of RPSC is rooted in a sophisticated system model that brings together three principal entities: users, regulators and the blockchain itself. Users are the primary participants, each equipped with a unique public-private key pair. Their public keys serve as identifiers within the system, while private keys enable the generation of privacy-preserving transactions. Depending on the application context, users may assume specialised roles, such as voters in an electronic voting system or bidders in an auction.  Regulators, typically government agencies or designated authorities, are granted the ability to view private data and trace transactions when necessary, using their own cryptographic key pairs. Importantly, regulators are restricted to observational and investigative functions. They cannot alter data on the blockchain. The blockchain, in turn, acts as a transparent, append-only ledger, hosting smart contracts that execute autonomously upon user interaction. Central to the RPSC system is the introduction of a multi-layer record commitment structure, which enables fine-grained privacy protection and flexible data state transitions. This multi-layer approach allows users to selectively disclose private data by replacing commitment values with actual data when necessary. For instance, in the event of a dispute or regulatory investigation, a user can reveal specific transaction details without compromising the privacy of unrelated data.   The construction of a transaction within RPSC is both rigorous and flexible. Each transaction consumes existing records and generates new ones, with the process governed by cryptographic protocols to ensure privacy and correctness.  To meet the regulatory traceability requirements, RPSC integrates public-key encryption and zero-knowledge proofs, specifically zk-SNARKs (Zero-Knowledge Succinct Non-Interactive Arguments of Knowledge). Users encrypt transaction details using the regulator's public key, ensuring that only authorised entities can decrypt and access sensitive information. Zero-knowledge proofs are employed to verify the correctness of transactions without revealing underlying data, thereby maintaining both confidentiality and integrity.  Transaction regulation in RPSC is achieved through a two-layer encryption mechanism. When a user initiates a transaction, a copy of the private transaction data is encrypted using the regulator's public key. This allows the regulator, and only the regulator, to decrypt and access the detailed data for oversight purposes.    The RPSC system represents a significant advancement in the design of privacy-preserving smart contracts for account-based blockchains. By combining multi-layer commitments, zero-knowledge proofs and regulatory traceability, RPSC offers a balanced solution that addresses the needs of privacy, programmability and accountability in decentralised applications. The system’s ability to reconcile the demands of privacy and regulation, without sacrificing efficiency or programmability, marks a new paradigm in the development of smart contracts and decentralised applications.    Source: Innovation Digest