As you know, bus bodywork is a team effort in which several areas participate in a perfectly coordinated manner, all of them fundamental and indispensable. At Castrosua, one of these areas is Engineering. This area is divided into three sections (R&D+i, Homologations, and Technical Office), and it is made up of highly qualified personnel for the different functions performed within them. José Fernández Dios is in charge of the Engineering Department, with a total of 35 years of experience in the bodywork sector, 26 of which he has spent at Castrosua. Thanks to his extensive professional career, José Fernández has a perfect understanding of the Department’s operations, both at a production and technical level. Today, we want to delve into his work and that of all his colleagues in Engineering, first-hand. This is what he told us: 
You are a veteran at Castrosua, what advances have been made in recent years in the company’s Engineering Department?
It has changed in many aspects. Firstly, the team has grown: about 10 years ago it consisted of 6 people, and now we are 15. Secondly, it is a more trained team, and there has been a qualitative leap in staff training. This is also due to the need to apply new design tools, more suitable for generating the documentation we need (software such as SOLIDWORKS, AutoCAD, ADOBE ILLUSTRATOR, CorelDRAW, EPLAN), requiring a certain degree of specialization. In short, human and technical resources have been strengthened over the years. This gives us the capacity to generate all technical documentation with the reliability and detail required for the bodywork process. Most brands allow us direct access to bodywork standards and guidelines and provide us with 2D and 3D files of different chassis models. Design software allows us to apply different construction solutions and facilitates the obtaining of laser or plasma cut parts, which was not possible with the available means before. We also produce drawings of the different electrical wiring harnesses for outsourcing, as well as connection diagrams for Manufacturing.Certainly, the Engineering Department has grown and improved significantly in these 26 years. We know that the way of working is also different today. Can you tell us a bit more about how it worked in the past?
Previously, the Technical Office generated the minimum and essential documentation for each Manufacturing section to carry out its work. In Structure, the information was quite detailed and complete, as it had to be, since the vehicle must be dimensionally defined, meet Homologation requirements, and adhere to the brand’s bodywork guidelines. With the help of templates and formers, the necessary structural sub-assemblies were manufactured. In Sheet Metal, for example, the documentation provided was more limited; drawings of the side hatches, passenger doors, driver’s bulkhead, settling tanks, etc., were provided. Small parts and various supports were developed directly by the section head with the support and guidance of the Head of the Technical Office or Prototypes. I will always remember the way the driver’s bulkheads were manufactured, entirely of galvanized sheet metal at the bottom, and the skill of the sheet metal workers who made them. Initially, Castrosua had a Polyester section where all polyester parts were laminated with their respective reinforcement fittings. Gradually, this in-house manufacturing was reduced, and the supply of these parts was outsourced to external suppliers. In addition to their responsibility for organizing work, the section heads contributed their experience and knowledge in resolving many construction details. When we lacked information requested by the client, such as the vehicle’s electrical diagrams, we had the support of the Electrical section head, who provided us with the information and reviewed the final diagrams. We are now completely autonomous in this area and generate the necessary diagrams to order wiring harnesses from suppliers or for assembly in manufacturing. The lists of drawings were smaller, partly because there were other needs and the vehicle equipment was more basic, and also because many parts were made in-house using templates and formers. Now, the lists of drawings for Purchasing and Manufacturing are more extensive, including the plasma or laser cut parts we generate in the design. To ensure documentation traceability, in addition to these lists of drawings, we create lists of polyester and plastic parts (ABS, thermoformed, 3D printed) for each vehicle.How do you work in the department? What is your day-to-day like?
We have different functions. On one hand, there is the R&D+i part, where we work on developing new projects, designing parts, defining manufacturing and assembly processes, and exploring the application of new materials. On the other hand, there is the operational part of the Technical Office, dedicated to generating all documentation related to Manufacturing and Homologation files. The people in the Projects area share the Commercial files, so each file has a Project Manager assigned, who is also responsible for identifying potential difficulties and proposing solutions before starting to prepare the Purchasing or Manufacturing drawings. We also attend the daily Manufacturing meetings, providing solutions to incidents or problems raised, offering technical assistance to Sales and After-Sales, and working on generating 3D printing models and parts.We are experiencing a transition towards zero-emission buses (electric, CNG). Is your team’s effort strong in this regard?
Absolutely. It has been many years since we began this transition towards buses with lower emissions, including CNG, hybrid, electric, and fuel cell. We are in contact with brands and Engineering Project companies to explore cooperation possibilities for the bodywork of their platforms and even the transformation of already bodied vehicles. Some of these include EVO MOVILITY, HYUNDAI, IVECO, BYD, KING LONG, REE, etc. How do you feel after the positive reception of the Nelec?
We feel very good, actually. Everyone involved in the development of this Project trusted in their capabilities and assimilated that we were capable of carrying it out, despite the great challenge it represented. We must also mention that we had the support of some external companies like KORBA, P. BIDASOA, or VENTURA, and technology centers like IDONIAL, CTAG, NAITEC, who helped us integrate new components into the bodywork, design parts, and perform dimensional analysis of ducts. With the successful completion of this Project, our Engineering team has gained expertise and self-confidence to transfer this experience to other similar Projects. As a highlight, it was a pleasant surprise to see how the different polyester parts and other components we received from suppliers fit into the prototype’s structure. It has been a great satisfaction for us to see how the polyester parts, designed and generated by us from scratch, fit perfectly in place. When we presented the vehicle, all the components and parts installed were definitive and functional (doors, air conditioning unit, signs, windshield wipers, indirect vision systems, ramps, etc.); none were installed provisionally. To everyone’s satisfaction, the Nelec moved under its own power, and all its equipment worked.The bodywork design is practically digitized. What are the advantages of this digitalization?
The advantages of digitalization are numerous. It allows us to design tooling and formers based on the 3D structure. With it, we can perform finite element analysis of the structure’s behavior in case of rollover, avoiding the construction of test modules. It also simplifies the iteration process in case of modifications due to non-compliance. In the commercial sphere, it allows us to make virtual presentations of the product that are completely aligned with the final reality. We can also say that it allows us to start projects earlier, as we are not dependent on having a module or chassis to attach the structure to in order to develop many fundamental parts. In short, it facilitates the study and analysis of assembly solutions for many components without physically having them, performing air distribution analysis along the duct, or, based on our 3D structure and the 3D chassis, designing and generating the surfaces of the necessary exterior and interior cladding parts. 
