Abstract: A mathematical model of the limited angle steel belt transmission system is established to analyze its transmission characteristics and the influence of pre-tension on its output characteristics，and the influencing factors of the limited angle steel belt creep rate and transmission ratio are studied. Based on the rigid-flexible coupling dynamics model and the mathematical model for calculating the pre-tension force of steel belt，the influence of pre-tension force on the output characteristics of the transmission system is studied through the multi-body dynamics simulation software and the physical prototype experiment.The results show that the thickness of steel belt，the rolling angle，the ratio of rolling angular velocity to steel belt transmission speed，the transverse displacement and the radius of friction wheel are the main factors affecting the creep rate and transmission ratio of steel belt. The larger the pre-tension force is，the smaller the deviation of output angle is，the higher the output precision is，and the more stable the transmission is. When the pre-tension force is 11 N，the overshoot is 40% and the output angle error is 6.4%. When the pre-tension force increases to 84 N，the overshoot decreases to 1%，the response time decreases to 20%，and the output angle error decreases to 1.4%.The mathematical model of creep rate，transmission ratio and pre-tension force can provide theoretical basis and effective reference for the research on limited angle steel belt transmission system.

Key words: limitedanglesteelbelt, pre-tensionforce, transmissioncharacteristic, creeprate, rigid-flexiblecoupling