Biomechanical analysis on Japanese woodworking work

对两名熟练木工和多名非熟练木工的日本手工刨削动作进行了生物力学分析。熟练的木工表现出一些优秀的技能点如下。即手工刨削开始时刀刃对木材的起始位置、姿势位置、左右手臂的推拉力条件、腰部的水平移动以及刨削结束时刀刃对木材的停止位置。从生物力学的角度，我们可以找到这些优秀的技术点，并建立了五个分类项目，对熟练和非熟练木工的日本手刨动作进行分类。第一项是木质材料的顶部与手刨底部之间的位置关系。第二项是主体姿势与木质材料端部的位置关系。第三项是通过肌电图测量的四块肌肉的操作。第四项是腰部水平移动距离。第五项是木材端部与手刨刃口和底面的位置关系，从生物力学角度对日本熟练和非熟练木工的各种手刨动作进行了分类，形成了由五项组成的类型图。并从生物力学和分析学的角度验证了教学对型图的影响。

We analysed the Japanese hand planing motion about two skilled woodworkers and many unskilled woodworkers on the type chart biomechanically. The skilled woodworkers showed some excellent skilled points as follows. Those are the start position of the knife edge to wood material at the beginning of hand planing, the position of posture, the condition of push force and pull force by right and left arms, the horizontal moving of waist and the stop position of the knife edge to wood material at the end of planing. We could find these excellent skilled points biomechanically.And we established five classificaton items to classify the Japanese hand planing motion about skilled and unskilled woodworkers. The first item is the relation of the position among the top of wood material and the bottom of hand plane. The second item is the relation of the position between the posture of subject and the end of wood material. The third item is the operation of four muscles measured by the electromyogram. The fourth item is the horizontal moved distance of waist. The fifth item is the relation of position among the end of wood material and the knife edge and the bottom of hand plane.The various Japanese hand planing motion about skilled and unskilled woodworkers could be classified on the type chart composed by five items biomechanically. Also we could confirm the effect of teaching on the type chart analytically and biomechanically.