目的 使给袋式包装机实现更加精确、平稳的取袋送袋。方法 通过建立取袋机构的数学模型，得到包装机允许空间内大、小臂铰链点的位置可行域及初始安装角范围；以封闭矢量法计算出末端执行器运动学参数解析式；应用Matlab编程得到其运动学曲线图谱并进行分析。结果 优化后当大臂长l1=360 mm、小臂长l2=200 mm、安装角=30时末端执行机构的运动学曲线轨迹过渡平稳、没有突变。结论 采用结构参数优化后的取袋机构具有良好的运动特性，能够实现更加平稳的取送袋。

The work aims to enable the bag-delivering packaging machine to pick up and deliver the bags in a more precise and stable manner. By establishing the mathematical model for the bag-picking mechanism, the feasible region of big and small arm hinge coordinates and the initial installation angle range in the allowable space for the packaging machine were obtained. The kinematical parameter analysis formula of the end effector was calculated in the closing-vector-circle method. Its kinematical curve spectrum was obtained and analyzed with Matlab program. After the optimization, when the big arm length l1=360 mm, small arm length l2=200 mm and installation angle =30, the kinematical curve track of the end effector was in a stable transition without sudden change. The bags can be picked up and delivered more stably by adopting the bag-picking mechanism with the optimized structure parameters.