基于CMM的曲面反求夹具设计

Design of Surface Reverse Clamp Based on CMM

用三坐标测量机反求曲面,读取曲面上的点在空间位置坐标时,如果不按曲面矢量方向接触曲面会出现测量误差。针对这一问题,提出测量曲面的关键是按矢量方向接触曲面,减小测量余弦误差,基于此设计一个测量曲面的夹具,通过改变测量夹具三坐标板角度使测量方向和曲面法向重合,达到减少测量误差的目的。以鼠标曲面轮廓为例,用设计的夹具反求曲面,实验的结果表明,夹具起到了方便取曲面上的点,且不用改变侧头角度的效果,减少了测量误差。

Reverse surfaces with three coordinate measuring machine,readed the points on the surface coordinates in space,if not follow the direction of surface vector contact surfaces,measuring errors appeared.To solve this problem,proposed the key technique for the measurement of surface of three coordinate measuring machine according to vector direction of the contact surface,reducing the measuring error.Based on this,designed a fixture for measuring surfaces,made measurements directions and normal coincide by changing angle of measuring clamp plate to redude errors.Took the mouse surface profiles for example,designed the fixture for reverse surface.Experimental results show that the fixtures play the effects of pick up point easily on the surface and without changing lateral head angle,and reduce measurement error.