Commercial multi-degrees-of-freedom (multi-DOF) myoelectric hand prostheses can perform various hand gestures and grip motions using multiple DOFs. However, as most upper limb amputees have less than two electromyogram (EMG) signals generated at the amputation site, it is difficult to control various hand gestures and grip motions using multi-DOF myoelectric hand prostheses. This paper proposes a multifunctional myoelectric hand prosthesis system that uses only two EMG sensors while improving the convenience of upper limb amputees in everyday life. The proposed system comprises a six-DOF myoelectric hand prosthesis and an easy and effective control algorithm that enables upper limb amputees to perform various hand gestures and grip motions. More specifically, the hand prosthesis has a multi-DOF five-finger mechanism and a small controller that can be mounted inside the hand, allowing it to perform various hand gestures and grip motions. The control algorithm facilitates four grip motions and four gesture motions using the adduction and abduction positions of the thumb, the flexion and extension state of the thumb, and three EMG signals (co-contraction, flexion, and extension) generated using the two EMG sensors. Experimental results indicate that the proposed system is a versatile, flexible, and effective hand prosthesis system for upper limb amputees.

This study aims to develop a controller and graphical user interface for validating the gait performance of a prototype knee prosthesis. Current research on knee prostheses focuses on developing hybrid systems that combine passive and active walking modules. Therefore, it is essential to conduct gait function validation experiments for modules, and clinical gait trials. Previous studies have validated the gait function of assistive devices through simulations or conducted clinical trials where patients wore backpacks containing the controller, instrumentation, and batteries. However, validating gait performance in virtual reality has limitations, and studies have shown that wearing a backpack during walking can affect gait. This study aims to address and improve upon these limitations. The controller developed in this study includes five essential experimental functions. First, it measures the response time of the passive walking module to validate its performance in adapting to changes in gait events. Second, it evaluates the initial assembly condition of the active walking module. Third, it measures the maximum degrees per second of the active walking module, assessing speed at different knee angles during the swing phase. Fourth, it measures the maximum torque of the active walking module to pre-assess its ability to provide the necessary torque for transfemoral amputees when descending stairs or slopes. Finally, the gait algorithm is validated in a real walking environment. These five experiments validate the mechanical gait performance and the software-based gait algorithm of the knee prosthesis, promoting the development of high-quality knee prostheses and improving the quality of life for knee amputees.

This paper proposes a myoelectric hand prosthesis with an easy control strategy to apply more conveniently with just two EMG sensors. The myoelectric hand prosthesis is composed of a multi-DOF finger mechanism, a controller, and an intuitive control algorithm. The developed hand prosthesis has 6-DOFs and can perform eight hand motions using the intuitive control algorithm. The proposed intuitive control algorithm classifies four grip motions and four gesture motions; we used the thumb position of the hand prosthesis and three EMG signals (Co-contraction, flexion, and extension) generated from the two EMG sensors. From the experimental results, we demonstrated that the proposed myoelectric hand prosthesis is applicable to amputees as a hand prosthesis.

This study introduces an electronically controlled pneumatic knee (ECPK) prosthesis designed to enhance gait adaptability and stability in transfemoral amputees. While pneumatic prostheses are lightweight and cost-efficient, they often lack responsiveness and stability. Therefore, a 4-bar linkage mechanism with a pneumatic cylinder is implemented, along with a motor-driven control algorithm using a unipolar Hall sensor to adjust damping based on real-time gait phase detection. A dedicated PC application is also developed to monitor gait parameters and configure control settings. Gait experiments with a transfemoral amputee demonstrate that an ECPK prothesis improves step length symmetry, dynamic stability, and responsiveness over fixed-nozzle and conventional pneumatic prostheses. These findings suggest that the ECPK prosthesis effectively bridges the gap between simple mechanical design and adaptive performance, providing a practical and scalable solution for improving prosthetic gait support.