Contents lists available at ScienceDirect Robotics and Computer–Integrated Manufacturing journal homepage: www.elsevier.com/locate/rcim Energy-optimal layout design of robotic work cells: Potential assessment on an industrial case study Michele Gadaleta a , Giovanni Berselli b , Marcello Pellicciari a, ⁎ a Department of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, Modena 41125, Italy b Department of Mechnical Engineering, Energy, Managment and Transportations, University of Genova, Genova 16145, Italy ABSTRACT This paper presents a new method for optimizing the layout position of several Industrial Robots (IRs) placed within manufacturing work-cells, in order to execute a set of specified tasks with the minimum energy consumption. At first, a mechatronic model of an anthropomorphous IR is developed, by leveraging on the Modelica/Dymola built-in capabilities. The IR sub-system components (namely mechanical structure, actuators, power electronic and control logics) are modeled with the level of detail strictly necessary for an accurate prediction of the system power consumption, while assuring efficient computational efforts. Secondly, once each IR task is assigned, the optimal work-cell layout is computed by using proper optimization techniques, which numerically retrieve the IR base position corresponding to the minimum energy consump- tion. As an output to this second development stage, a set of color/contour maps is provided, that depicts both energy demand and time required for the task completion as function of the robot position in the cell to support the designer in the development of an energy-efficient layout. At last, two robotic manufacturing work-cells are set-up within the Delmia Robotics environment, in order to provide a benchmark case study for the evaluation of any energy saving potential. Numerical results confirm possible savings up to 20% with respect to state-of- the-art work-cell design practice. 1. Introduction Industrial robotics may be envisaged as the most strategic technol- ogy that can practically enable flexible automation and intelligent manufacturing processes. Unfortunately, Industrial Robots (IRs) and related peripheral machines are intrinsically energy intensive, thus compromising the overall factory sustainability. In particular, as previously proven in several researches (e.g. [1,2]), IR massive adop- tion heavily impact both factories ecological footprint and overall production costs. In addition, many companies are currently facing severe issues related to the actual unavailability of electric energy supplier, which can withstand the peak power requirements as the number of IRs simultaneously employed within the same location exceeds a certain threshold. Naturally, owing to this restriction, any further industrial development may end up being heavily damped, or even impossible. Therefore, the industrial need towards possible strategies to reduce the energy consumption (EC) of single IRs and/ or robotic work cells at factory level is unquestionable. Within this scenario, current and past research activities concern- ing mechatronic eco-design methods have been rapidly gaining a strong foothold in the scientific arena, resulting in an increasing number of programs funded by both academia and industry [3]. For instance, energy optimization by means of IR electromechanical hard- ware replacement is addressed in [4]. At robotic cell and process design level, energy-optimal robot selection for specific operations is investi- gated in [5], whereas many past works deal with energy-optimal path generation, see e.g. [6]. In [7], novel methodologies aim at achieving an EC reduction while avoiding plant revision. These techniques are based on the optimization of the IR velocity profiles without affecting productivity and quality, thus providing interesting solutions that should aid programmers to develop more sustainable applications without affecting investment costs. For what concerns IR positioning, the layout design of a robotic cell is a delicate task performed under conflicting requirements: on one hand, robots and peripheral equipment must be placed assuring best reachability and process performance; on the other hand, design rules that assure safety and ease of maintenance must be strictly observed. Owing to these concurrent needs, along with the lack of industrially- viable engineering tools, the design of robotic work-cells is currently tackled with a trial-and-error approach mostly based on the designer http://dx.doi.org/10.1016/j.rcim.2016.10.002 Received 8 December 2015; Received in revised form 6 October 2016; Accepted 6 October 2016 ⁎ Corresponding author. E-mail address: marcello.pellicciari@unimore.it (M. Pellicciari). Robotics and Computer–Integrated Manufacturing xx (xxxx) xxxx–xxxx 0736-5845/ © 2016 Elsevier Ltd. All rights reserved. Available online xxxx Please cite this article as: Gadaleta, M., Robotics and Computer–Integrated Manufacturing (2016), http://dx.doi.org/10.1016/j.rcim.2016.10.002