# Survival 1.0: A Novel Autonomous Industrial Mobile Warehouse (AIMW) for Industrial Environments
## 1 Introduction
### Management of Spare Parts Warehouses for Maintenance Operations  
In factories, there are not only warehouses with raw materials or manufactured products, there are also warehouses with spare materials for use in maintenance tasks. Management of the latter is not as complex as other warehouses since the tasks do not change over time. In this case, the replacement materials with a higher probability of use are placed near the warehouse exit, thus reducing the time to obtain the replacement parts. However, in large factories, such as automobile manufacturing, the distance between the central warehouse and the place where the breakdown occurs can cause very long delays. For this reason, there are smaller warehouses located throughout the plant, containing the most common materials needed to perform typical repair tasks. If we take into account the materials that are placed at the exit of the central warehouse as an independent warehouse, what is being done is to replicate this smaller warehouse with the most typical materials throughout the factory to minimize access times to the necessary materials and, therefore, minimize the time to repair the fault.  
At Ford's factory in Almussafes (Valencia) there are 170 of these warehouses distributed throughout the plant, see Figure 1. The materials contained in these warehouses are basically the same: capsules, clamps, fittings, gloves, photocells, detectors, etc. The difference between them is marked by whether there is any line that instead of having a photocell A has a B one due to its characteristics, although the objective of the factory is to standardize them and make them the same.  
The distribution of these cabinets is regular throughout the facilities, allowing the maintenance and production operator to have access to spares near the manufacturing line and thus reduce the repair time of the fault, which is defined as the MTTR (Mean Time To Repair). For this spare parts maintenance system, it is necessary for some storekeepers to go through the pre-established routes, deliver the required materials in each area when they are not stored in the cabinet or are simply not found among the common parts, and obtain the data of the requested materials using a barcode reading system to minimize human error.  
The spare parts delivered to the different facilities are small in size and are distributed according to the name of each MWG (Manufacturing Work Group), that is, the manufactur  
Figure 1: Cabinets with most common spare parts.  
ing line, see Figure 2. Although a barcode is used to try to minimize human error, during the process of distribution of spare parts by the operator, confusion and errors often occur that make the distribution system inefficient.  
Currently, there is a recent trend towards robotic and human collaboration [3; 4]. This trend is closely related to Industry 4.0 and, more generally, to IIoT concepts. It has been fuelled by recent developments in the world of Information Technology and industrial electronics or even materials science. Enabling technologies for these trends are, e.g., smart sensors [5] for a better perception of a robot's environment, and industrial communications [6; 7] for improved real-time interaction and coordination not only among robots but also between them and their environment. In this context, wireless communications have played a decisive role, since they support the mobility of robots, as well as the inclusion of sensors or actuators around the real robot [7].