Abstract：Objective This work is aimed to providing a new technology for online wear monitoring of artificial knee joint. For this purpose, the stress change during the wear process of the artificial knee joint is studied by using the finite element technology, and a signal acquisition system is designed to capture the vibration signals induced by the wear of knee joint prosthesis. Methods In order to effectively collect the vibration signals, the dynamic model of knee joint prosthesis during motions was analyzed to determine the best installation position of vibration sensor. The dynamic model of the knee femoral prosthesis was solved by the Lagrangian equation to obtain its torque curve. Then the finite element technique was used to analyze the contact mechanics of tibial pad under different degrees of freedom, which can provide a basis for the installation of vibration sensors. Results The stress concentration regions of tibial pads under four degrees of freedom, including buckling, internal and external rotation, anterior-posterior displacement, and up-and-down displacement, were obtained based on dynamic simulation. The analysis results indicate that the stress concentration is obvious in the middle andposterior regions of the tibial pad. Hence, the vibration signal with higher amplitude can be collected when the vibration sensor is installed at the rear end of the tibial pad, which is helpful for the vibration feature extraction of the knee joint prosthesis. Conclusions The vibration signal acquisition system designed based on dynamic simulation analysis can effectively collect the vibration signals generated by the artificial knee joint during the wear process. This investigation provides an important technology to explore the wear mechanisms of artificial knee joints and monitor its full-life health status.