DESIGN OF A LINEAR ACTUATOR FOR THE POSITIONING SYSTEM OF SPACE TECHNOLOGY PRODUCTS

Positioning systems are widely used in space technology products and are most often equipped with linear drives based on screw mechanisms. Currently, the most promising screw mechanisms are planetary roller screw gears (PRSG), which have high efficiency and have high load capacity, rigidity, reliability and durability. This is the basis for their use in the aerospace industry. For high accuracy it is necessary to use backlash-free mechanisms in which the gaps are selected in various ways. For the projected positioning system it is used a backlash-free PRSG with a flexible one-piece nut made in the form of a “short” cylindrical shell and developed ends. The gaps are selected by deforming the flexible nut by bending moments. A structural diagram of the positioning system has been developed, its components (bearings, clutch, etc.) have been selected, the calculation of the power mechanism based on a gas-free gear system has been performed, which has shown high gear operational characteristics. Meanwhile, the PRSG has been calculated for static and dynamic load capacity. Furthermore, the value of the static load capacity of the designed gear has been determined. Prerequisites have been created for the development of design documentation for the components and parts of the positioning system and primarily for the backlash-free PRSG.