## 6 Conclusions  
In a context of emergency due to COVID-19 expansion and shortage of PPEs supply in the healthcare system, a solidarity project carried out by the UCLM produced 23,500 3D parts in 40 days assisted by FDM 3D printing to cover the needs of Castilla-La Mancha (Spain).  
During the first days of the project, the requests were attended via a centralized model, which was highly inefficient and caused delays in deliveries. Therefore, a web information system was developed ad-hoc to help in the transition towards a decentralized model. During the second stage, and despite the increasing number of requests, the times of response were quickly reduced down to two days, facilitating planning of the fabrication units and reducing costs related to distribution. The use of the web information system also allowed reaching more destinations and remote areas that could not be attended to during the first stage.  
The design of a recommender module for the assignment of requests to fabrication units, according to their workload or availability and the distance between origins and destinations, has also been an important contribution resulting in significant benefits in terms of time and costs. This experience shows the advantages of using technology to develop systems that improve internal processes in any social cooperation. In particular, this work aims to be an example that encourages non-profit associations to consider the need to undertake the digital transformation to improve their processes and achieve their objectives.  
The project has allowed protecting healthcare professionals in about 280 locations in the region, mainly in the provincial capitals, manufacturing about 13,000 face protection items and about 11,000 ear-savers. The healthcare and law enforcement sectors have been the main beneficiaries. In particular, 13,917 PPEs have been supplied for health professionals (60.4% of the total), and 2733 for law enforcement officers (11.79% of the total).  
Conceptualization, M.C.-G. and J.C.-V.; Formal analysis, J.A., J.J.C.-S. and J.C.P.-F.; Funding acquisition, J.A.; Investigation, J.A., J.J.C.-S., J.C.P.-F. and J.C.-V.; Methodology, J.A., J.J.C.-S. and J.C.-V.; Resources, J.C.P.-F. and J.C.-V.; Software, J.A. and J.J.C.-S.; Supervision, J.A., J.J.C.-S. and J.C.-V.; Validation, J.A., M.C.-G. and J.C.P.-F.; Visualization, M.C.-G.; Writing-original draft, J.A. and J.C.P.-F.; Writing-review and editing, J.J.C.-S., M.C.-G. and J.C.-V. All authors read and agreed to the published version of the manuscript.  
The authors would like to thank every individual, company or institution for their financial support via the UCLM crowdfunding campaign. Thanks also to our colleagues at UCLM for their contribution coordinating, manufacturing and distributing the 3D printed materials. The authors are also very grateful to the civil protection service and different bodies of the police for their help to distribute the produced PPEs, especially during the lockdown.  
The authors declare no conflict of interest.  
Figure 15: Average time of services (number of days). Average time, in days, needed to attend the applications. The data are recorded per week, from 16 March to 4 May 2020.