Mechanical communication in multiple robot system

In this paper, authors proposes an idea of “mechanical messaging” for inter-robot communication using actuators and force sensors equipped on robots. In their previous works, they have proposed the decentralized multiple autonomous monopedal robots system "Universal Unipods" for universal object transportation. Their statement is that a very simple yet widely applicable function such as object transportation can be helpful for many kinds of tasks and the Universal Unipods can be served for literally universally. The robot of the system is very simple both in mechanisms and algorithms. It doesn\´t even have a device for inter-robot communication in spite of being an element of multiple robots system. However, if the robots could communicate each other, they would perform more advanced manoeuvres of object transportation. Then, authors introduce "mechanical messaging" in this paper. It is a way of communication without any extra devices except actuators and sensors which are originally equipped on each robot. Robots apply modulated force on the load as broadcast messages while "listen" them by force sensors. The fundamental validity of this idea is verified by the Universal Unipods system through computer simulation.