This article analyzed the preparation methods of ferroelectric photovoltaic thin films. This article analyzed the modeling of impact mechanics, including mass distribution, boundary conditions, and loading conditions, to ensure appropriate load transfer and joint stability; in the simulation, it was found that the material properties included photovoltaic and ferroelectric properties, which were suitable for the production of knee joint protectors. From these data, it could be found that the deformation of protector 2 was smaller than that of protector 1, indicating that the PZT material in protector 2 could better fix the protector and prevent significant deformation due to impact behavior. It had a higher hardness value, representing higher wear performance. The results of this article highlighted that sports knee joint protectors based on PZT materials could better cope with impact behavior, extend the lifespan of the protector, and protect the wearer's knee joint.