中文摘要：

以现有NuVinci无级变速器为研究对象，对其传动特性进行分析。建立其运动学和动力学数学模型，得到传动比、滑动率、传动效率和承载转矩等各项传动特性与各结构参数之间的关系式，并利用MATLAB语言编程计算得到各特性随结构参数的变化规律三维曲面图。研制无级变速传动试验台进行试验研究，试验结果表明所建立的理论模型是可靠的，为Free-Ball型无级变速器的结构参数优化设计打下了基础。

英文摘要：

In order to design the Free-Ball type CVT more reasonably and rapidly, the analysis of the transmission characteristic for the NuVinci CVT has been carried out. The mathematical models for Nu- Vinci CVT kinematics and dynamics analysis of NuVinci CVT have been established, and the relations be- tween the transmission ratio, sliding ratio, transmission efficiency, load torque and the structural parame- ters have been obtained. The three dimensional surface diagrams of these relations have been got through using Matlab language. Besides, the test-bed of this CVT has been developed. The experimental results show that the established theoretical models are correct, which has laid foundation for the selection of the structural parameters and optimization design for the Free-Ball type CVT.