Coordiate Meassuring Machine and Reverse Engineering.pptVIP

CMM and Reverse Engineering CMM Reverse Engineering CMM-Introduction Flexible dimensional measuring device Contact-sensitive and non-contact principle. Measuring procedures Variant level of CMM automation Application occasions Quality inspection Digitizing device for reverse engineering CMM construction Three main types bridge type gantry type ： greater rigidity, but smaller slide acceleration, restricting access for automatic loading of components cantilever type: shorter measuring time A granite surface plate as a base Air bearings is used to ensure smooth motion of the slide Different way of movement of the machine axes Lower-priced: entirely manual; handweels; More expensive: motor-powered DCC CMM: by programming Operational cycle description Preprogrammed inspection programs for each different workpiece reside at the host computer; downloaded on demand to the CMM computer Could you imagine and describe the inspection procedures of CMM Importance to Flexible cells and systems Inspection routines are done swiftly and automatically Control the overall process so that it makes only quality parts Reverse Engineering CMM—traditional solution for 3D measurement contact digitisation Small triangulators, auto-focusing device and laser stripes integrated in CMMs; wide area laser scanners and whole-field optical digitisers—optical gauges non-contact not a very high measurement accuracy A limited invasiveness higher speed of measurement a lower cost Definition of reverse engineering 三维激光扫描仪 Reverse engineering system for rapid manufacturing of complex object the way后面的定语从句 例1： ①　I dont like the way in which you speak to her. ②　I dont like the way that you speak to her. ③　I dont like the way you speak to her. 解析： 在句1中，which代指先行词the way，定语从句的逻辑语序为you spark to her in which，意为“你用那种方式和她说话”。因which代指the way，故用in和which搭配。分析从句的成分可知，in which在从句中为方式状语。 根据定语从句的句法规则，in which引导定语从句作方式状语时，in which也可使用that代替，或者省略引导词，也就是句2和句3的表达方式都是正确的。需要注意的是，句2中的that并非前文所说的代词性的th