Transportation of a large object by small mobile robots with handcarts and outrigger

In this paper, we report on our efforts to transport a large object by small mobile robots in a home or office environment. Given such an environment, robots must be compact. We improved the transport capacity of small mobile robots using a handcart. However, there were two problems faced: the risk of a slip and fall under the influence of the reaction force when the robot handles the object, and the slipping of the handcart as the robot stacks an object on it. To address slipping, we gave the robot the ability to press a nonskid board on the floor with respect to both the robot and handcart when necessary. To prevent the robot from falling, the moment is counteracted with a device similar to an outrigger, which is often used in mobile work vehicles. We constructed a prototype of the system to implement the proposed method, and confirmed its effectiveness by performing a transport experiment.