Stefan Bartscher

Towards control and sensing for an autonomous mobile robotic assistant navigating assembly lines

There exists an increasing demand to incorporate mobile interactive robots to assist humans in repetitive, non-value added tasks in the manufacturing domain. Our aim is to develop a mobile robotic assistant for fetch-and-deliver tasks in human-oriented assembly line environments. Assembly lines present a niche yet novel challenge for mobile robots; the robot must precisely control its position on a surface which may be either stationary, moving, or split (e.g. in the case that the robot straddles the moving assembly line and remains partially on the stationary surface). In this paper we present a control and sensing solution for a mobile robotic assistant as it traverses a moving-floor assembly line. Solutions readily exist for control of wheeled mobile robots on static surfaces; we build on the open-source Robot Operating System (ROS) software architecture and generalize the algorithms for the moving line environment. Off-the-shelf sensors and localization algorithms are explored to sense the moving surface, and a customized solution is presented using PX4Flow optic flow sensors and a laser scanner-based localization algorithm. Validation of the control and sensing system is carried out both in simulation and in hardware experiments on a customized treadmill. Initial demonstrations of the hardware system yield promising results; the robot successfully maintains its position while on, and while straddling, the moving line.

Mobile Robots for Moving-Floor Assembly Lines: Design, Evaluation, and Deployment

Robots that operate alongside or cooperatively with humans are envisioned as the next generation of robotics. Toward this vision, we present the first mobile robot system designed for and capable of operating on the moving floors of automotive final assembly lines (AFALs). AFALs represent a distinct challenge for mobile robots in the form of dynamic surfaces: the conveyor belts that transport cars throughout the factory during final assembly.