IntroductionMachining aims to generate the shape of work-piece form a solid body，or to improve the tolerances and surface finish of a previously formed work-piece，by removing excess materials in the form of Machining is capable of creating geometric configurations，tolerances， and surface finishes often unobtainable by any other However， machining removes materials， which has already been paid for， in the form of relatively small particles that are more difficult to recycle and are in greater danger of becoming Therefore，developments often aim at reducing or-if at all possible-eliminating machining， especially in mass For these reasons， machining has lost some important markets， yet， at the same time， it has also been developing and especially having captured new markets with the application of numerical Some feel for the important of machining may be gained from the observation that in 1983 there were about 2 million metal-cutting machine tools in the unite states ( of which some 5% were numerically controlled ) and that labor and overhead costs amounted to $125 billion， or 3% of the GNP
electrical and hydraulic compound nanopositioner This design is in the motor - driven magnetroheological on the basis of the installation of hydraulic system so that it is common to give impetus to magnetroheological line round feed the design of complex nanopositioner motor part by the ball screw drives hydraulic part by hydrocylinder actuaton magnetroheological， by the second part of the design of the main stage of the mechanical structure design， appreciating and hydraulic system There are several aspects: magnetroheological of the transmission mechanism design， mainly the application of the ball screw; magnetroheological blockmodel laryngofibroscopy design， understanding， take full account of the main controdiction， grpwth ystems; control system design， familiarize its application stepmotor feed can be accurate location but there are shortcomings is inadequate， so the output will be considered as a hydraulic motor power source and stepmotor of compound feed system hydraulic feeding， although they could not be located， but with high output force， pre-language educatiuon， so that the feed motion can accurately so that productivity has risen
