Quintic Interpolation Joint Trajectory for the Path Planning of a Serial Two-Axis Robotic Arm for PFBR Steam Generator Inspection

Prototype Fast Breeder Reactor (PFBR) has eight Steam Generators (SGs). Inspection of SGs requires a remote tooling to reach the probe pusher module to each of the 547 tubes present. Since the tube sheet reach has a planar workspace, a two-axis Selective Compliant Assembly Robotic Arm (SCARA) type of manipulator suits well. However, the geometry and size of the manipulator are based on the workspace and space constraints which are very well represented in the kinematic studies through the DH parameters. However, the position or velocity inverse kinematics solution for the tube to tube movement results in discrete position or velocity points. So for precision movements with good control on speed and position, we prefer position and velocity-based moves through the motion controller. In order to maintain continuity on accelerations and jerks while controlling velocity points require a choice of higher order polynomial. This paper presents the quintic interpolation method (quintic polynomial trajectory) for planning a joint trajectory of two-axis robotic arm. The quintic interpolation and the case study of PFBR steam generator inspection are presented. The quintic interpolation ensures the continuity of displacement, velocity and acceleration for the planned motion of joint trajectory of two-axis robotic arm.