| Reviewing the past 20th century, every great scientific and technical result that the mankind made is closely related with manufacturing technology, especially the ultra-precision machining. The ultra-smooth free-form surfaces are more and more important in the fields of modern optics and photoelectron discipline, national defense industry and ultra-precision moulds. The corresponding ultra-smooth machining technologies become the important part of modern ultra-precision machining technology too.The latest development stage of ultra-smooth free-form surfaces machining technologies is mainly to study a series of non-contacted polishing equipment and methods. These are the brand-new machining method from the machining mechanism to equipment. Those become the sign of development direction of ultra-smooth free-form surfaces machining.Polishing by hand is time-consuming, efficiency is low, and difficult to make good precision of form and surface quality, This restrain from the automatic degrees of ultra-smooth free-form surfaces machining technologies greatly. The appearance and applications of industry manipulator and robot, which inject new vigor for polishing and its automation machining. Robotized equipment that raises the automation degree is the important development direction of machining automation. It is feasible to develop the research of ultra-smooth free-form surfaces machining technologies on the basis of the platform of robot.In this paper, it is developed that hydrodynamic suspension polishing system for ultra-smooth free-form surfaces based on robot. The system is composed of YR-SV3-J00 robot, polishing equipment, speed variable motor, XY work table,computer and so on. It is shown as figure 1. In the routine technology of polishing, the optics polishing is the method to obtain minimum surface roughness. However, should be exceeded the smooth free curved surface, must change or adopt the machining method of the new principle to the already existing machining technology.In recent years, at the foundations of tradition polishing technology, there appear new-type ultra-precision and dissociate abrasive machining method, such as EEM, liquid polishing, hydrodynamic polishing, magnetic fluids polishing, abrasive extrusion lapping, magnetic abrasive finishing, rotation grinding and Jet machining and so on.In this paper, according to the principle of elasto-hydrodynamic and elastic emission, hydrodynamic suspension polishing system is established. Polishing region is shown as figure 2. Abrasive grains are suspended in the slurry and move with the fluid because of the rotation of polishing tool. There is hydrodynamic pressure close to the small area on the work piece surface. The abrasive grains produce synthesized function to work piece surface by elastic emission and mechanical strike.It is analyzed theoretically that the course of polishing by tradition and micro friction and wear theory. Through elastic emission and elasto-hydrodynamic, abrasive grains can produce function of micro cut and extrusion and plastic deformation wear and friction corrosion and wear. According to the theory of micro friction wear, in the course of polishing abrasive grains impact on top layer atom of the work piece, weaken the binding energy of the top layer atom constantly. Then when collide the next time, the top layer atom will come off. Abrasive grains collide the micro convex area constantly because of centrifugal force in the slurry, thus the binding energy of the top layer atom is weakened constantly, the work piece surface is removed with the molecule or atomic grade.In the course of polishing, abrasive grains produce the impact in succession to the work piece surface, make the work piece surface stand the circulation load. There are shear plastic deformation and accumulate constantly in the top layer and appear periodic dislocation. In the course of friction, shear deformation accumulate constantly, dislocation are accumulated in the certain degree of depth place under t...
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