A novel non-circular gear slider-crank mechanism was proposed to make pulsating blood flow generators produce stable pulsations of blood flows.The blood flow pulsations were real-ized by the combination of non-circular gears and slider-crank mechanisms.In order to make the de-signed mechanism run smoothly,the acceleration curves of the output components of the mechanism were fitted by the 2 sections of cubic Hermite interpolation polynomials under the preconditions of satisfying the law of human body blood flow pulsations,and then the equations of velocity,displace-ment and jerk of the output components were deduced according to the equations of the acceleration curves and the boundary conditions.The non-circular gears section curve reverse model was obtained by the output component kinematics curves equations.The 3D solid model of this mechanism was es-tablished based on mechanism parameters obtained from instance analysis and the virtual prototype test was performed after modeling.The comparison between the results of virtual simulation experi-ments and theoretical analyses shows that the designed mechanism may realize the pulsating blood flows according to the laws of expected,and the mechanism has fine kinematics characteristics,also verifies the correctness of the equation of kinematics curves and the kinematic analysis model.%为使脉动血流发生器产生稳定的脉动性血流,提出了一种新型非圆齿轮-曲柄滑块式驱动机构,运用非圆齿轮副和曲柄滑块机构的组合传动来实现血流的脉动.在满足人体血流脉动前提下,为使设计的机构运行平稳,采用2段三次Hermite插值多项式来对该机构输出构件的加速度曲线进行拟合,再由加速度曲线方程及其边界条件推导出速度、位移和跃度曲线方程,运用拟合得到的输出构件运动学曲线方程推导出非圆齿轮副节曲线反求模型.根据实例求解分析得到的机构参数进行三维建模和虚拟样机实验,对比虚拟仿真实验和理论分析结果,发现所设计机构能够按照预期规律实现脉动血流,且该机构具有良好的运动学特性,同时验证了所构建的运动学曲线方程及所建立的运动学分析模型的正确性.
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