NavVis, rapid prototyping of portable scanners, through additive manufacturing

It is the world’s most accurate portable mapping device with SLAM (Simultaneous Mapping and Localization) technology. Fast, accurate and compact, it allows operators to efficiently acquire the data needed for visualization in the AEC sector and beyond.

The task of developing such a revolutionary piece of hardware fell to NavVis industrial designers Sarah Godoj and Nils Christensen. To accomplish this formidable task, they used the power of rapid prototyping to test and refine the design.

The result? The ideal balance between precision, accessibility and ergonomics of the device – validated with Ultimaker 3D printers.

“It’s a wonderful engineering marvel on the part of our team,” Nils said. “If you want, you can go on a hike with the NavVis VLX.”

Focus on the sensors

Headquartered in Munich, Germany, NavVis specializes in developing next-generation technologies that enable accurate mapping of interior spaces. And given that the accuracy of the NavVis VLX wearable system had to compete with terrestrial solutions, the positioning of the scanner sensor would be the designers’ top priority.

After many iterations, the team came up with an innovative design that combines two multi-layer LiDAR sensors and four high-resolution cameras. Together, they measure and map a 360-degree view of the internal space, mounted the perfect distance above the operator’s head to keep them out of sight and allow the user to see everything in the environment.

But soon after deciding on the basic concept, the designers realized that they also wanted to differentiate the NavVis VLX from other portable scanners in that the NavVis would not be attached to the user’s back, to avoid bumping into something when the user turns in tight spaces.

Sarah explained: “We used alternatives such as wood and cardboard, but closer to the final project we didn’t consider anything else as there was no better alternative than 3D printing.”

Everything at your fingertips

This led to a complicated and unique challenge: making every user-scanner interaction extremely accessible. In particular, the touch screen required many iterations. It had to be in the field of view, but still allow the user to see the floor to find ground control points and avoid dangers.

With so many variables to find the best viewing angle and positioning, the team once again turned to 3D printing to validate their ideas.

Joining PVC pipes with 3D printed cable ties allowed them to test configurations as quickly as possible. PVC pipes can easily be cut to any length, leaving only the corners to 3D print.

“We wanted to have precise angles to really demonstrate the power of CAD,” Nils said. “This meant it was the perfect mix of rapid prototyping and true precision.”

With this technique, the team also tested the dimensional accuracy of their Ultimaker 3D printers. While all 3D printing involves a little shrinkage as the material cools, they solved the shrinkage by printing multiple connectors with a 0.1mm difference between each version.

Custom design

“Creating a device that fits the human body comes with many challenges,” Sarah explained. “But with 3D printing, we could do many iterations to get a good combination of size and weight right.”

The team’s goal was to create an ergonomic experience where the user felt like they were wearing a backpack on their chest. To simulate that weight, they loaded water bottles onto a 3D-printed wooden skeleton. If any test users found it uncomfortable, Sarah and Nils knew they would have to make a change.

This was especially necessary for the shoulders. To find an optimal design, the team adjusted the Ultimaker Cura settings to create quick «draft» prints before moving on to detailed prints. This approach ensures that the straps are comfortable for everyone, with no chance of the NavVis VLX slipping off.

Another ergonomic challenge was safely storing the device in a case that a single user could quickly transport and set up on site. For this a folding mechanism would be necessary. But where should the NavVis VLX safely fold to achieve the smallest volume? Again, industrial designers used 3D printing to verify the CAD model. They left holes in the arms and temporarily attached them with a long screw inserted into the 3D print used for the simulation.

Rapid prototyping in a pandemic

To create these rapid iterations, the team relied on the Ultimaker 2+ and Ultimaker S5.

Thanks to the reliability of the printers, Sarah and Nils developed a 24-hour iteration cadence that allowed them to test new ideas as quickly as possible: «On Friday you hit ‘print’ and on Monday the product is ready.»

Of course, when COVID-19 forced most designers to work from home, their workflow had to change and rely on the remote 3D printing functionality of the Ultimaker S5 and Ultimaker Digital Factory.

They could safely monitor their print jobs and simply ask someone in the office, «could you remove the print and press ‘confirm’?» To avoid having to add new filament during printing, they also installed a second webcam to monitor the spools. That way, they could continue to iterate regardless of pandemic restrictions.

Nils said: «We always thought 3D printers were a bit complicated, but Ultimaker was a nice, easy-to-use solution. They always explain the next step or what’s happening now.»

This ease of use has meant that, although the team is made up of 15 designers and mechanical engineers, they all 3D print parts and «no one is afraid to touch the Ultimaker».

Continuous improvement

Because NavVis builds its scanners to order, the design team continues to iterate and improve their products using 3D printing. Nils revealed: «Every development step we do mechanically, 80% of the time we 3D print it first. Doing this instead of creating parts from blocks of metal with a lead time of up to five weeks. You can imagine it’s quite economical.»

Nils and Sarah continue to refine their 3D printing process. And thanks to Ultimaker’s open filament system, they contribute to NavVis’ sustainable goals by increasingly printing with recyclable materials.

In this way, they help NavVis build a better world, as well as better indoor scanners.