An evaluation methodology for the conversion of manual assembly systems into human-robot collaborative workcells

A collaborative robot is an industrial robot, which is able to interact physically and safe with humans in a shared and collaborative hybrid workspace. Collaborative robots are introduced helping operators to perform manual activities in modern manufacturing systems combining human inimitable ability with smart machines strengths. Considering current small and medium enterprises, the introduction of industrial collaborative robots involves the retrofitting process of current production systems, which in many cases is the starting point for collaborative process development. Due to the fact that collaborative assembly will be one of the most challenging and interesting applications for collaborative robotics in the near future, a proper human-robot assembly activity division will be a fundamental part of that retrofitting process. The aim of this work is the development of an evaluation methodology for the conversion from a purely manual assembly workstation into a collaborative one, by considering human and robot activities separation. The proposed model in this paper is based on a technical, qualitative and economic evaluation of the current manufacturing system in order to identify if there is the possibility to successfully re-design the workstation by introducing a collaborative robot in an efficient way. Safety and ergonomics indexes are also considered in order to improve operators work conditions between the current and the desired situation. (C) 2019 The Authors. Published by Elsevier B.V.