Concept of interchangeable of small-sized and mechanical spare parts already became reality namely in 19 centuries (basically be to pass firmer ground to control dimension public errand) . Present task is to want to produce the large whole part that has interchangeability and complex form part (be like aviation spare parts) , decrease major general to these spare partses are aimed and assemble the labor that is a component concentrated model (also be very costly accordingly) working procedure. The development director Jim Dallam of company of United States of MAG of machine tool manufacturer says, "Strict dimension public errand maintains to be accomplished not hard inside very short distance along linear axis, but it make sure along aleatoric contour line and direction dimension precision wants inside the dimensional limits that should be in a few meters is difficult to make sure along aleatoric contour line and direction dimension precision wants inside the dimensional limits that should be in a few meters much. " he points out, although large whole part has interchangeability inside limits of dimension public errand, but this kind of public errand often too big, they realize down to very hard truly but crossing-over (have perfect consistency namely) . What have 1 stere or bigger size range of pipe bent to be in is large it is difficult that this is overcome to plant in treatment of 5 axes machine tool, MAG company rolled out error of a kind of space to compensate (VEC) system, this system can is opposite at the same time the integrated method of all movement rod and position error have the machine tool fast analysis and amend. Error of this kind of space compensates a method to be able to compensate affirmatory error the time of a need to shorten from a few days. VEC system and method are by a government / of industry combine development and test and verify, the algorithm that develops with the Philip Freeman of branch of research and development of company of You Bo news is a foundation. A kind of when VEC system can regard MAG as new machine tool optional configuration is offerred, can carry the technical service department of MAG company, undertake to vintage machine tool with VEC system the spot upgrades transform. Dallam explanation says, VEC system uses laser of a T3 to dog lens of target of an appearance, activity and by automatic and accurate company (Automated Precision Inc.
) the measurement of development software (VEC measurement technique also is offerred by this company) will correct geometrical appearance error. Laser dogs the stimulates beam of light to shoot installation to go up in machine tool main shaft mobile target lens that appearance gives out (illuminator) on, illuminator will stimulate beam of light to reflex an illuminant again. Numerical control program has fixed position to illuminator, create 200 dot cloud of the dot, it represented a series of 5 axes inside limits of machine tool work " pose " (statement position) . Dallam says, "Laser dogs lens locks up appearance and mobile target to stimulate beam of light surely from beginning to end, accordingly, move when the machine tool and stop in a position when, laser dogs appearance knows target lens the position in true space, the machine tool also knows its place in instruction space. " after moving through 3, the model that software can build place to require dimensional compensation (group of polynomial simultaneous equations) . When method is mobile, of system of machine tool control compile circular function to undertake to these equation groups real time is handled, can raise a machine tool to machine precision greatly thereby. Introduce according to Boeing company, in a few large plans (be like F-18 battleplan and Boeing 700 model the production of series aircraft) in, error of this kind of space compensates a system to assemble and assemble cost through be being reduced significantly, be expected every year to save 100 million dollar. CNC Milling