Development of Hybrid Power Supply System for Mobile Robots

A trend toward robotic research has shown that mobile robots nowadays play more important roles in service tasks than ever. Mobile robots have been changed in their sizes a lot from gigantic instruments in manufacturing plants, as in the past, to the moderate machines in today’s office building, hospitals or houses. However, mobile robots are kept away from being compact because the weight of onboard batteries become a constraint toward the size and weight of robots itself. Given the technology of today, a battery-driven robot cannot work for long on a single charge. Development of a new powerful technology for batteries may take many exhausted years.

In this research, a dual-energized scheme called HYbrid POwer Supply (HYPOS) methodology has been proposed. During the specified missions, the electricity for mobile robots is available from two types of energy sources; battery and household electricity. The technique is that a robot is supplied by household electricity through an electric cord during a task execution and to reduce the effects of electric cord, we attempt to use a short cord and let the robot change connections between multiple outlets autonomously. The robot is allowed to find and connect to a household electric source by supplying of an onboard battery. The significant of HYPOS system is that a HYPOS robot can work during recharging a battery. The challenge of implementing HYPOS system is to develop the outlet-connection procedures and to handle the electric cord to reduce movement disturbance.

Instead of developing a robot with full faculties, we let the environment provides some of them to help the robot. We have developed a special device call Power Supply Station (PSS) attached to the conventional outlet and let the robot connects to PSS instead. A cord-winding system has been developed on the robot and cooperated to the movement of robot. An experiment on sweeping task has shown that a HYPOS robot can work consecutively for long hours without breaking the operation for recharging the battery. The efficiency of HYPOS from the viewpoint of energy consumption is satisfied.

Keywords: Power Supply, Battery Problems, Service Robot

References

  1. Chatchai Wattanasin, et al.: A Hybrid Technique to Supply Indoor Service Robots, In Proc. the 1998 IEEE Int. Conf. on Robotics and Automation, Leuven, Belgium, May 1998 (to appear).

　

         

Fig. 1 Prototype HYPOS System                 Fig. 2 Image of HYPOS Concept