摘要
介绍了一种新型的用于纳米坐标测量机的三维微纳米接触触发式测头机构.本测头以灵敏度高、抗干扰性强的布拉格光纤光栅(FBG)为测量的敏感元件,根据FBG对轴向应变变化敏感的特点,开发了一套有效触发测量力小的柔性悬架机构,该机构为三悬丝-六边中心连接体的悬架结构,相间隔的3边延伸悬臂与3根布拉格光纤光栅相连,当测球发生预行程变化时,由测杆带动柔性悬架机构产生偏摆,从而带动3根FBG发生轴向的拉伸或压缩,进而产生传感信号的输出.由于测头结构复位性是衡量测球和工件分离后能否回到初始位置的标准,是测头其他各项指标的基础,因此结合激光干涉仪和精密微动平台,采用光学非接触干涉测量方法对该测头机构的实际复位性能进行了测量.结果表明,测头系统采用15 N的预紧力安装悬丝,可得到较好的复位性和灵敏度,该测头机构复位性精度在20 nm以内,满足微纳米量级高精度测量的需要.
A novel micro-nano touch trigger 3D probe of coordinate measuring machine（CMM） was proposed.Based on the high sensitivity and good anti-interference of fiber Bragg grating（FBG） sensor,FBG sensors were used as sensitive elements for the probe to measure the strain produced along the fiber.As FBG sensors were more sensitive to axial strain than to lateral strain,a flexible structure consisting of the three-wire and six-side connecting hanging structure with interval cantilevers connected with three FBG sensors was developed,which could be triggered by small strain produced by effective axial force.In case of pre-travel changes,flexible suspension caused deflection,leading to axial stretch or compression of the three FBG sensors,and thus the sensor signal output.The reposition performance of the probe mechanism is the criteria for judging whether it can go back to the initial location after measuring and is the basis of other performances of the probe.Therefore the actual reposition performance of the probe was tested with laser interferometer and precise micro-motion platform.Experimental results show that the application of the wire of 15 N pre-tighten force to the probe system can result in good reposition performance and sensitivity,with the reposition accuracy of the probe less than 20 nm,which meets the needs of micro-nano measurement.
出处
《纳米技术与精密工程》
EI
CAS
CSCD
2011年第3期249-252,共4页
Nanotechnology and Precision Engineering
基金
国家自然科学基金资助项目(50805043)
清华大学国家重点实验室开放基金资助项目(DL-002)
