A customized solution to meet the needs of 17 police units in Germany.

“Our biggest challenge is diversity,” Busam said. Each state and each police force unit procures many different types of vehicles, and each vehicle may also require additional customizations to suit its intended use. The components that need to be installed inside also vary. For example, each unit may use radio communication systems or signaling systems from different manufacturers. This means that each vehicle requires a lot of custom parts.

“We produce vehicles for 17 police units in Germany, and each unit has its own ideas about what the ergonomic layout should be and how it should be used. So, in terms of the basic design, the production volume may seem quite high, but when you add in the level of specific customization, the production volume becomes quite small again,” Busam said.

MOSOLF's team works by starting with standard, mass-produced vehicles, meaning they take commercially available cars, trucks, and vans and customize them by installing additional equipment to the required specifications. The team must find the optimal mounting locations for each requested function, ensuring the installation is ergonomic, durable, and aesthetically pleasing.

In older car models, finding installation space was easier because there was still plenty of free space in the dashboard or console for MOSOLF customization. However, in newer car models, it becomes a greater challenge.

"Modern cars have more and more display screens, making the interior feel cramped. There are no longer any spaces for installing additional equipment. Inside, there might only be a small storage compartment and a phone charger. Therefore, finding space to install all the control devices is challenging, especially in camouflaged vehicles, where it shouldn't be obvious that they are police cars," Busam said.

MOSOLF's journey with 3D printing technology began in 2016 when the Bavarian State Police ordered the installation of new digital radio communication systems on all vehicles and motorcycles in their fleet.

“We needed to find solutions specific to each car and each motorcycle. If we produced all the parts from sheet metal, it would be incredibly time-consuming, or the results wouldn't look good. That's why we first stepped into the world of 3D printing.”

Custom-made mounting brackets for the front LED flashing lights on a police van. Previously, the team used sheet metal forming to produce these parts.	Today, SLS 3D printing offers a significantly faster, easier, and more cost-effective solution.

Initially, the team produced parts using Fused Deposition Modeling (FDM) 3D printing, which at the time was the most accessible and suitable technology for their needs. However, they soon encountered some limitations. FDM printing was difficult to scale up to meet the required volume of orders, and the parts produced were not of industrial quality.

SLS 3D printing would seem like the ideal next step, but with solutions starting at around €200,000 , the technology was beyond the reach of small businesses until the launch of Formlabs' Fuse Series.

“SLS printing is perfectly suited for MOSOLF because it offers excellent quality, high precision, good material performance, and the ability to produce large quantities of parts simultaneously. It's also cost-effective, as the entire system is very affordable,” said Gerhard Duda, CEO and founder of 3D-WERK Black Forest GmbH, a Formlabs partner who has worked with the MOSOLF team from the beginning to find the optimal solution for their application.

“The Fuse Ecosystem is the best choice for us because, in terms of usability and workflow, it’s the easiest system for us to manage,” Busam added.

This speaker cover is designed to help save up to 70% on pre-installation costs. The speaker can be clipped directly onto the insert without the need for any glue or mechanical fasteners.

Custom-made, functional parts within 24 hours using SLS 3D printing.

Compared to traditional mass production processes such as injection molding , thermoforming , or sheet metal forming, the most significant advantage of additive manufacturing is its ability to produce custom-made or small-batch parts without the need for expensive molds.

“We use SLS technology, and specifically the Fuse 1+ 30W machine, to produce a wide variety of parts, from small, simple components to complex car consoles. We utilize this technology extensively, and the Fuse machine meets approximately 80% of our requirements,” said Tiberiu Morariu, Head of Prototyping, Design, and Technical Conception at MOSOLF.

MOSOLF's team uses SLS 3D printing to produce dozens of custom designs, ranging from small covers and tool boxes to large, multi-component assemblies and interior dashboard components.

“Requirements vary from state to state and from police station to police, so 3D printing makes the process much easier. You can quickly redesign one vehicle to another. If it’s the same model, the exterior will remain the same, but the additional systems installed inside can be vastly different,” said Morariu.

The radio mount is a prime example of customization. While the console mounting points are the same for all Mercedes vans, the overall assembly can be easily modified, using different mounts to accommodate radios from various manufacturers.

This ease of modification significantly speeds up both prototyping and production , especially when both prototypes and production parts can be manufactured on the same machine.

“For me, as a designer, there’s nothing better than having an idea in my head today, sketching it out, and then the next day being able to hold that piece in my hands and actually see it,” said Morariu.

“The biggest impact of 3D printing on in-house manufacturing is that it has allowed us to work significantly faster in many areas. With traditional manufacturing processes, we would have delivery times of around four to six weeks, especially if the part required surface finishing. But with 3D printing, we can provide parts virtually overnight. If we didn't have access to 3D printing technology, our workflow would likely be much longer and more complex, as we might have to produce and modify each part multiple times.”

Carsten Busam
Head of Project Planning
MOSOLF Special Vehicles GmbH

	SLS 3D Printing	Sheet Metal Forming	Thermoforming	Injection Molding
Timeframe from design → prototype → actual production of parts.	1–2 weeks	6–8 weeks	6–8 weeks	6–8 weeks
Lead time for actual use parts.	1–2 days	6–8 weeks	6–8 weeks	6–8 weeks
Other factors	No molds required, easily customizable, high design freedom, and superior aesthetic appeal.	Requiring molds or tools limits design options, making customization more difficult and resulting in lower aesthetic appeal.	The use of molds or tools has design limitations and is more difficult to customize.	It requires expensive, non-customizable molds and offers less design freedom.

“Today, vehicles are becoming more aesthetically pleasing. Interiors have more fluid designs, and storage spaces are more complex and diverse. 3D printing is therefore crucial to automotive design and ergonomics, as these aspects aren't always achievable with other technologies like thermoforming or sheet metal forming. Connecting components to these complex vehicle shapes is best solved by 3D printing. With 3D printing, I have greater design freedom and can fully develop my creativity in design and form.”

Tiberiu Morariu
Prototyping, Design and Technical Conception
MOSOLF Special Vehicles GmbH

This ventilation opening is a one-way valve used to separate the black compartment from the white compartment inside specialized vehicles used for arson investigations. Its structure is a relatively complex modular design, consisting of three parts fastened together with screws.

Initially, the team attempted to produce this part using FDM 3D printing, but encountered problems due to its circular shape and thin walls, making manufacturing difficult. They then switched to SLS 3D printing, which offered greater design freedom.

One of the key advantages of SLS 3D printing is that engineers are familiar with the mechanical properties of the materials used, such as nylon, which is widely used in the automotive industry for manufacturing both interior and exterior car parts.

The MOSOLF team has a thorough understanding of the performance capabilities of nylon parts printed using SLS 3D printing. Therefore, they are able to design with functionality in mind, and in some cases, even replace some existing metal parts.

Clip-on mounting bracket for the vehicle's cargo area, for a removable emergency light.	Ceiling light housing and mounting bracket.

“With the Fuse Ecosystem, you get the best materials naturally available—ready-to-use materials that have been used for a very long time and have been thoroughly tested,” said Duda.

Besides durability, one of the most important criteria for applications in the automotive industry is heat resistance. For materials used in FDM printing, PLA is definitely unsuitable due to its heat deflection temperature (HDT) of only about 50 °C at 0.45 MPa.

ABS has an HDT of approximately 90 °C at 0.45 MPa, which is better than PLA, but still considered to be within or below the optimal limit for many applications.

While Formlabs Nylon 12 Powder has a high HDT of up to 171 °C at 0.45 MPa, it has significantly higher heat resistance. This means that practical components, such as radio mounts, will not be damaged even if the vehicle is parked in a hot parking lot during the summer.

Housing for electrical outlet	A protective cover to prevent accidental damage that may occur while moving around inside the vehicle.

In some cases, vehicles are leased to police or emergency services, and after their lease period expires, they are sold to civilians or other government agencies.

To achieve this, MOSOLF's team needed to customize and install the additional equipment in the vehicle without causing any permanent damage or modifications to the vehicle itself, so that it could be easily reverted to its original condition at the end of its lifespan.

Additive manufacturing simplifies this process as well, because instead of permanently modifying the original part, the team can remove the original part and replace it with a 3D-printed part that can be removed and replaced later.

References

https://formlabs.com/blog/police-special-vehicles-sls-3d-printing/