A Novel Distributed Telerobotic System for Construction Machines Based on Modules Synchronization E. Rohmer and K. Yoshida Department of Aerospace Engineering Tohoku University Aoba 6 - 6 - 01, Sendai, 980-8579, JAPAN Email: {eric, yoshida}@astro.mech.tohoku.ac.jp Eiji Nakano Robot Technology Center Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, JAPAN Email: nakano.eiji@it-chiba.ac.jp Abstract—On a scene of a natural disaster, rescuers require heavy duty hydraulic machines to answer their need of large forces, or to approach an unreachable spot. Those industrial vehicles are hydraulically actuated arms kinematically different, and equipped by specific tools to fit the task to accomplish. They require trained operators because of their complex use. As time and accuracy are primordial factors to save lives in such a situ- ation, the use of automation and robotic concepts on the control of those machines becomes necessary. The standard approach is to use manual teleoperation based on a bilateral master/ slave system, to enhance the maneuverability of the machines, but their diversity is nearly never taken into account. We propose here, a modular platform based on an original synchronization of module states that allows easy manipulator changes and flexibility of use. We will describe the proposed concept of Intelligent Interface, and verify its utility and performances through some pertinent configurations and experiment. I. I NTRODUCTION When a natural disaster such as earthquakes occurs, quick and efficient recovery programs to minimize the loss of human life and facilitate rapid restoration and reconstruction are necessary. This process requires precise tools, a large vari- ety of heavy duty construction machines, effectively trained machines operators and the assurance that health and safety risks for the operator are reduced to a minimum. The use of telerobotic concepts offers the possibility of contributing to each of those requirements. Hydraulic machines are for most of them, similar to serial robots of different kinematics complexities, equipped by a specific tool to accomplish a specific task. But their traditional way of control is based on an independent joint control, where the operator is using a complex system of lever to operate separately each angle of the arm. The precise control of the trajectory of the tool requires a long training on machines. To be efficient, rescuers need to operate on simulated disaster scene. In some other cases, the operator needs to work from outside the cab, to get either another point of view, or to work from a remote safer place in case of a hazardous working site. Regarding these problems, the design of a new architecture for civil engineering machines must take into account the following constraints: • Maneuverability of the machines: how to cope with the complex system of levers and the complexity of the tasks, • Interoperability: how to add remote control features to the machines; replace a real machine by a virtual one, etc., • Diversity: how to deal with the numerous kinds of civil engineering machines and tasks. In this paper, we present a solution based on a new soft- ware architecture to allow the use of robotic and automation concepts with the civil engineering machines, that deals with those three issues. This architecture is based on the integration of a computer system using a modular approach based on synchronization of virtual images of manipulators, instead of a more common master-slave approach. In the first part, we show the problem inherent to traditional hydraulic machine use. In the second part, we describe the concept of the modular intelligent interface and describe its implementation. Finally, we show performances and advantages of the proposed platform, though some pertinent configurations. II. MANEUVERABILITY AND DIVERSITY OF MACHINES Here we detail the problem inherent to conventional ma- chines control that requires long training, to show the necessity of finding an enhanced way to manipulate civil engineering machines. At the same time, one should be able to notice the diversity of tasks and machines available to accomplish the very different kind of works that require as well a special training. A. Maneuverability of the conventional machines Due to their counter intuitive system of control, the operator needs a special training for each kind of machine, and each different task to be quick and efficient. 1) Controlling the position and orientation of the tool in the space: The conventional device to control hydraulic machines is corresponding to a system of levers directly connected to the valves that controls the pressure in the cylinders. The operator is then controlling each joints of the hydraulic arm separately,