本文介绍了自调整比例因子Ｆｕｚｚｙ－Ｐ控制理论，及非接触超声传感焊缝跟踪的原理．在理论分析和试验的基础上，确定焊缝跟踪系统的模糊控制规则，研制出焊缝跟踪系统中的自调整比例因子Ｆｕｚｚｙ－Ｐ控制器，并设计了控制器的硬件及软件．实验证明，该控制器提高了焊缝跟踪系统的响应速度和跟踪精度，可以满足实际工程应用的需要 This paper introduces the self-adjusting proportional-factor Fuzzy-P control theory, and the principle of non-contact ultrasonic welding seam tracking. Based on the theoretical analysis and experiments, the fuzzy control rules of the welding seam tracking system are determined, and a self-adjusting proportional factor Fuzzy-P controller in the welding seam tracking system is developed. The hardware and software of the controller are designed. Experiments show that the controller improves the response speed and tracking accuracy of the weld tracking system to meet the needs of practical engineering applications