Kinematics Characteristics Analysis for Wheeled Mobile Robots Applied in the Horizontal Pipeline Inspection with Constant Cross-section

This paper presents the analysis results of kinematics characteristics of a wheeled mobile robot applied in horizontal pipe inspection (WMRPI) and constant cross-sectional area. The mechanical structure of the robot is designed including main assemblies which are the drive cluster and the passive cluster. The hinged connecting rods and the spring joint ensure that the wheels of the robot create the suitable pressure on the pipe wall helping the robot move along to the length of the tube. Furthermore, the hinge rods can be stiffly adjusted to work with a wide range of pipes of different diameter sizes. The forward kinematics (FK) and inverse kinematics (IK) problems are established and solved to evaluate the kinematics factors of the robot in general and the wheels in particular. The FK problem is solved in three cases where the driving laws of wheels are different to consider in more detail the influence of these laws on the motion of the robot. The IK problem is solved with a programmed motion trajectory based on a given distance and total motion time of the robot. The research results provide the necessary information for dynamics and control problems in the use of different driven motors.