In this letter we present a control and trajectory tracking approach for wiping the train cab front panels, using a velocity controlled robotic manipulator and a force/torque sensor attached to its end effector, without using any surface model or vision-based surface detection. The control strategy consists in a simultaneous position and force controller, adapted from the operational space formulation, that aligns the cleaning tool with the surface normal, maintaining a set-point normal force, while simultaneously moving along the surface. The trajectory tracking strategy consists in specifying and tracking a two dimensional path that, when projected onto the train surface, corresponds to the desired pattern of motion. We first validated our approach using the Baxter robot to wipe a highly curved surface with both a spiral and a raster scan motion patterns. Finally, we implemented the same approach in a scaled robot prototype, specifically designed by ourselves to wipe a 1/8 scaled version of a train cab front, using a raster scan pattern.
Moura, J., McColl, W., Taykaldiranian, G., Tomiyama, T., & Erden, M. S. (2018). Automation of Train Cab Front Cleaning with a Robot Manipulator. IEEE Robotics and Automation Letters, 3(4), 3058-3065. https://doi.org/10.1109/LRA.2018.2849591