Mass-Produced BEVs Manufacturing
Applying Our Commercial Vehicle Manufacturing Experience to BEV Production Preparation
O.H：
I have been involved in production preparation for commercial vehicles, including the Hijet, which serves as the base vehicle for this model. I have also worked on specialpurpose vehicles and overseas models, so I have often had to figure out how to manufacture vehicles with structures and production processes that differ from standard models on an existing production line.
For this commercial mini BEV, I worked on the production engineering side to ensure the vehicle design incorporated everything needed for mass production at the plant. Although it is based on the Hijet Cargo, converting it to a BEV dramatically changes the underbody structure and adds a battery, motor, and other dedicated components. Our first major challenge was figuring out how to manufacture that vehicle on our existing production line.
K.T：
I started out on the assembly line before moving into production preparation and process improvement. For this commercial mini BEV, I was involved from a manufacturing perspective during development, and later from a production engineering perspective as we prepared for mass production.
I had felt for some time that I needed to deepen my understanding of BEVs. I also took part in a demonstration project where we manufactured vehicles almost entirely by hand. Getting my hands on the vehicle and working through each challenge, even when I did not yet have all the answers, became valuable experience that has carried over into this project.
Having worked on the assembly floor, I was always thinking beyond the drawings. Even if something looked fine on paper, I wanted to know whether operators could actually assemble it, and whether they could keep doing so comfortably within the production takt time. So for this project, my focus was not simply on whether the parts could be assembled, but on whether the vehicle could be built consistently on the existing production line.
Making the Most of Our Existing Equipment
O.H：
Just because the vehicle has a new structure does not mean we can immediately introduce new equipment. Floor space is limited, and there are also investment and ongoing maintenance costs to consider. That is especially true for lowvolume production vehicles, where making the best use of existing equipment is essential.
We have extensive experience manufacturing specialpurpose vehicles by adding a wide range of equipment to our standard models. Our approach has always been to build as much as possible using the same process as the standard vehicle, while assembling dedicated parts or major structural differences in a special-purpose vehicle area. We took the same approach here. Just because it is a BEV does not mean everything has to be treated differently. Anything that could be shared with the standard model stayed on the same process. The real question was how to accommodate only the areas that were different. That was what we spent our time working through.
Take the newly designed rear suspension, for example. During vehicle assembly, it has to be installed together with the motor, making the structure quite different from anything we had dealt with before. Our existing lifter could not handle it, and we even considered adding new equipment. But after discussing ideas as a team, we came up with a two-stage configuration that allows us to install it within the existing process. We also redesigned the fixture that holds the ESU, the electric vehicle control unit, so it could run through the same production line as our engine-powered vehicles. That solution came from asking ourselves how these new components could fit into the line we already had.
Each improvement may seem small on its own, but by building on them one after another, we were able to produce the BEV without significantly disrupting the flow of the standard production line. To me, making the most of an existing production line is not simply about avoiding new equipment. It is about creating a manufacturing environment that can adapt flexibly to change.
K.T：
I also think our ability to move quickly was a major advantage during this launch. At Daihatsu Motor Kyushu, when an issue came up, people from different departments were close enough that we could talk to each other right away. It was easy to say, “Could we borrow this for a bit?” or “Could you give us a hand here?” Of course, that also meant we had to think through the solutions ourselves. We tried an idea first, and if it did not work, we improved it. This cycle was how we pushed the project forward.
Learning by Doing, Then Making It Work on the Production Floor
K.T：
Many of the structures we dealt with were completely new to us. To figure out how to assemble the rear suspension, we started by studying vehicles with similar layouts, taking them apart, and rebuilding them ourselves. We also obtained the certifications required to handle batteries and made sure we had insulated gloves and safety shoes. We studied unfamiliar structures, determined what we needed, and if something did not exist, we made it ourselves. It was a very hands-on beginning, and while it was certainly challenging, I honestly enjoyed it.
One thing I always keep in mind is whether what we create is genuinely easy for people to use. If it is difficult to use, people will eventually stop using it. We watched how operators worked, looked for anything that made their jobs harder, and improved things little by little.
When it came to installing the battery, we wanted to avoid introducing large-scale equipment. Instead of building a lifting device to raise the battery, we came up with a method of lowering the vehicle onto the battery during assembly. The difficult part was making sure the mounting holes on the vehicle and the battery lined up perfectly. We first considered using lasers or locating pins, but found that the process became awkward if it wasn’t level and ended up tilted. In the end, we solved it with a much simpler approach by lowering chains through the holes in the vehicle body and feeding them through the corresponding holes in the battery. Finding an effective solution with a simple mechanism instead of relying on large-scale equipment was one of the key innovations in this project.
Finding Solutions Together with Other Departments and Suppliers
O.H：
Once we actually started running the vehicles down the production line, unexpected issues naturally came up. We even encountered errors we had never seen before, and there were times when we spent days trying to understand what was happening. After the production line stopped for the day, everyone involved would gather together, run the vehicle through again, recreate the issue, observe its behavior, and work through the possible causes one by one.
What I really appreciated was that no one ever said, “That’s a design problem,” or “That’s a production line problem.” No matter what the issue was, people from manufacturing, inspection, quality assurance, and design all came together to help. Even when the issue originated in the design, we worked together to figure out how manufacturing could make it work. I think that collaborative way of working made a tremendous difference.
K.T：
This project also gave us the chance to work not only with manufacturing, production engineering, and design, but also with the evaluation, durability testing, procurement teams, and our business partners. We saw firsthand just how much preparation our business partners put into delivering parts with consistently high quality. It really drove home how many people work incredibly hard to bring a single vehicle to market.
Understanding how our suppliers manufacture their parts is just as important. Rather than asking for things based on our own needs, we need to understand their production processes and the challenges they face in making those parts. Without that understanding, it is difficult to arrive at improvements that are practical and realistic.
The Toughest Challenges Lead to Better Manufacturing
O.H：
One thing this project taught me is that even when you do not know the answer, if you keep learning, keep trying, and accept a few failures along the way, you eventually become capable of things you could not do before. None of us knows exactly how the future will unfold, whether it will be electrification or some other type of fuel. Even so, I want to be the kind of engineer who never stops asking, “How can we make this happen?”
K.T：
I also hope younger engineers will not give up when they run into difficulties, but instead enjoy the challenge of working through them. As for me, I want to keep taking on new challenges as well. Whether it is digital transformation, machining, processing, or welding, if I believe a technique is worth trying, I want to explore it myself. I want to become someone people can say, “If we ask that person, we will find a way to make it work.”
O.H：
We put so much effort into bringing this vehicle to life that nothing would make me happier than seeing many people use it and feel that it is truly a good vehicle. In areas such as mountainous regions where gas stations may be far away, the ability to charge the vehicle at home could make everyday use much more convenient. It could also serve as a source of power during emergencies. I hope to carry everything we learned through this project into the next generation of vehicle development.