Professor Liao Wei-hsin, Chairman of The Chinese University of Hong Kong (CUHK)’s Department of Mechanical and Automation Engineering, recently won the 2023 Leonardo Da Vinci Award from the Design Engineering Division of the American Society of Mechanical Engineers (ASME). Professor Liao is the first scholar from Hong Kong to win the ASME Leonardo Da Vinci Award in its 45-year history.

The ASME commended Professor Liao for his outstanding contributions to the design and invention of machines and devices for human motion assistance, with applications in prostheses, exoskeletons and wearables such as smartwatches and wristbands.

Professor Rocky S. Tuan, Vice-Chancellor and President of CUHK, congratulated Professor Liao, remarking, “This prestigious accolade is a fine tribute to Professor Liao’s contributions to the design and invention of machines and devices for human motion assistance. His commitment to technological advancement has been a great inspiration to the global community. The University and I are proud of his achievements and passion for innovation.”

Professor Liao said, “I am honoured to have received the award from the ASME. This is a recognition of our research and achievement in machine design, and I am grateful to the University for all the support over the years. I hope our invention will make an impact on society and inspire the next generation of youngsters.”

Inventions that get people moving

Professor Liao has led his team to important advances in machine design over the years, in particular three inventions for human motion assistance: a powered ankle-foot prosthesis, a magneto-rheological series elastic actuator for robotic exoskeletons, and human motion energy-harvesting apparatus and conversion.

The powered ankle-foot prosthesis developed by the team can provide net power to the wearer. The wearer can use it to regain a gait that is smoother and more natural, and the human effort in walking can be reduced by 15% or more compared with commercially available passive prostheses. The magneto-rheological (MR) series elastic actuator for exoskeletons can generate large controllable braking torque while consuming little energy. Novel MR actuators can improve energy efficiency by 53% and prolong the working time of batteries by up to 112%. The output power and power density of the embedded generator are more than 10 times higher than those of the existing products.

Furthermore, the lightweight energy harvester was developed to capture biomechanical energy from the motion of the human knee and convert it to electricity that can be used to power wearable electronics such as smart watches. This revolutionary device made possible the dream of generating an inexhaustible and sustainable power supply just from walking.

These innovative designs won three gold and three silver medals at the International Exhibition of Inventions Geneva between 2018 and 2022.