This paper describes design and implementation of a vision based platform for automated refueling tasks. The platform is an autonomous docking system in principle, with the specific application- refueling of vehicles. The system is based on monochromatic, monocular vision, and it utilizes very specialized image processing schemes. Image processing consists of very fast filtering and segmenting algorithms, as well as moment?s computation. A robotic arm with 6 joints (FANUC M-6i), and a controller unit (R-J3), does the physical work. A serial interface, with very high-level commands, connects a supercomputing machine and the robot?s controller. A practical setup would probably be scaled down to a special design robot, and a single processor controller with special VLSI chips for image processing. Results are very promising; the robot can identify the cap position, orientation, and height in real time with acceptable accuracy and reliability.