Estimation of Sloshing Motion in a Wheel-based Drain Inspection Robot

During navigation of a wheeled robot on the uneven terrain, the robot platform undergoes unbalanced ground reaction force force. When the wheel robot carries partially filled liquid container, the ground reaction force may cause liquid sloshing motion. Sloshing is an important factor that determines the stability and performance of liquid-carrying robot. This work presents the sloshing motion of a drain inspection wheel-based robot that contains a container with partially filled insecticides and sprays insecticides at the stagnant water location. The platform can attain two configurations with the help of a wheel tucking mechanism. These configurations help the platform to navigate in concrete and muddy terrain conditions. We carry out experiments to obtain the variation of liquid height due to the sloshing motion. The variation of the liquid height was measured by using three ultrasonic sensors at different movement and speed condition of the robot. Results show that the sloshing substantial and its essential to consider the sloshing motion while modeling the wheeled robot platform. Hence, we develop an analytical formulation of coupled robot-sloshing model which can be used to capture the variation of slosh liquid height under different excitation forces acting on the robot.