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The advanced high vacuum equipment for micro lithography and for surface analysis uses multicoordinate precise positioning actuators. The analysis, design and parameters of the new magnetic rheology (MR) drive are presented. The combination of MR loop control with elastic carriers and thin wall seals ensures small error of linear („T 50 nm) and angular („T 0,2 ang. sec) positioning, small time of response „T 200 ms and large total linear travel on three coordinates X,Y,Z 10 mm and load capacity more then 1000 N.
The actuators parameters: precision of positioning, time of response number of freedom degree also as error of positioning, static friction forces are being conducted. It was shown, that the error of positioning of the actuators with a loop control system is determined by static friction force [1] in range from 0, 01 N to 100 N, that corresponds to error of positioning in a range from 1 nm to 10 mic. The micro lithography actuator (X-ray) should provide error of positioning less 20 nm. The response of the actuator is determined by time of response on a control signal, which value of time should not exceed 200 ms [2]. The matrix analysis method shows, that the design of the drive being searched may be presented as a drive with elastic guides and magnetic rheology control and it is an optimal version on parameters: precision of positioning, time of response, number of freedom degree.
The parameters of vibroisolation systems are a cruelty and a viscose friction coefficient of a liquid. The viscose friction coefficient depends on dynamic equivalent viscosity. The control system measures two main parameters: the amplitude of hesitation and acceleration and these two parameters change the main performances of the actuator and reduce the amplitude and the acceleration that helps to move object to the check point. Because of this the magnetic rheology actuator can to operate as an active system of vibroisolation. The investigation of parameters: precision of displacement and response time of the vibroisolated system is being conducted. As a result of the work are presented: 1- three coordinates hydraulic actuator with vibroisolation, 2- nanopositioning function in one module.
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