Co-ordinated motion control of gantry systems

Abstract

Among the various configurations of long travel and high precision Cartesian robotic systems, one of the most popular is the H-type which is more commonly known as the moving gantry system. In this configuration, two motors which are mounted on two parallel slides move a gantry simultaneously in tandem. An example of this stage is shown in Figure 4.1. This gantry system consists of four sub-assemblies, viz., the X and Y-axis sub-assemblies, the planar platform, and two orthogonal guide bars. When positioning precision is of the primary concern, direct drive linear motors are usually used and fitted with aerostatic bearings for optimum performance. Another setup of H-type gantry stage is shown in Figure 4.2. It consists of two X-axis servo motors: SEMs MT22G2-10 and a Y-axis servo motor: Yaskawa’s SGML-01AF12. This gantry configuration has been in use for large overhead travelling cranes in ports, rolling mills and flying shear.