downhand

(非标准术语“平”麽意思？

What does the nonstandard term “downhand” mean ?

The concept of motion planning for welding positioner is discussed, and the mathematical model of rotating/tilting positioner under the downhand welding position is created.

对接变位运动规划的任务行了分解,建立了旋转倾斜型接变位使待点处于最佳接位置时的数学模型,并编制了求解程序,对空间螺旋线型行了模拟。