Introduction
In a previous post, I did a reconstruction of the back of my IONIQ 5 in order to find lettering appropriate for matching the naming of my vehicle to a children’s show that features a transforming robot that takes on the form of the IONIQ 5. I haven’t printed those letters yet, but that will be up soon on my todo list.
In the meantime, someone asked me about privacy concerns they have with modern vehicles and is specifically interested in the IONIQ5. For this person, whose privacy needs may exceed my own, what the car reports back matters a lot. And we now know that car data is being used in a variety of ways in the US where we lack appropriate privacy regulations:
Curious about how to reduce the invasive collection of data myself, and thinking the cell signal emanated from the fin on top of the car (it does not, it’s in the head unit inside the car), I got to testing, masking off my fin with copper tape, basically a fancy version of a tin-foil hat:
Initial Outcome
So, while this didn’t block the cell signal, it does make it impossible for the car to know where it’s at on cloudy days, almost entirely disables satellite radio, and makes digital radio perform poorly as well. It might also drive my wife a little crazy.
So I got to thinking of my original plan which was to 3D print a removable or controllable hat. The reason I hadn’t taken this approach is a shiny black fin is hard to scan. But, as it turns out, a weathered copper fin scans quite nicely with its complicated and diffuse reflections:
One step deeper…
Scanning the fin
So, I got to work taking lots of pictures. To keep referencing simple, I threw a metric folding ruler in the mix, and got a really nice reconstruction of the fin and ruler that I was able to scale to real world size, clean up, and prepare for the next steps.
Model as shown in WebODM:
Orthophoto in WebODM of fin and rooftop (notice issues with texturing on reflective portion of rooftop):
Model loaded into Blender and scaled to known size:
Editing and cleanup of model
Solidyfing model
In order to get an appropriate shape that would fit over the fin, I used solidifying modifier with positive offset in Blender, and then cleaned up the model using the 3D-Print Toolbox extension:
Addition of spots to add magnets for attaching to roof of car.
Conclusion (for now)
More to come. Wish me luck on the fabrication. Hopefully I am close enough on my scale. It will be interesting to have this removable, but it also might be nice to fabricate a version that can be remotely enabled or disabled with a thin mesh that can be connected to or disconnected from ground remotely.
I’ll also work on a similar scan of the head unit of the car where the cell antenna actually resides.