Let's just say this is an oldie but a goodie. Back when Creality released the CR-30 belt printer, Joel the 3D Printing Nerd commented that it would be nice to have a way to mount a camera on some of the extrusion, noting that most of the options he was aware of were not a good fit. Either the mount, or the camera would be in the way of the extruder, or the frame would be in the way of the camera. I realized that being able to offset the camera just might solve both problems. No idea if Joel ever grabbed the model, but the design on TinkerCAD has been copied dozen's of times, so let's see if it's something people want to work with here.
There are 2 parts in this model set. 1 of the two has the 3 blade attachment needed for most gopro and small sports cameras. I found the model at https://www.tinkercad.com/things/iLifMeAUme0-gopro-mount-w-nut, and remixed it with a 45 degree offset between the base and mount point. I also recognized that not all of the various sport cameras I was looking at used the same mount side. So I remixed my own model into a 2 blade solution.
The general plan is to use standard t-nuts and bolts to mount the base to 2020 or similar extrusions. This should work regardless of whether the extrusion is 2020, 2030, 2040 or 2080, v-slot 2020 variations, and possibly t-slot often used in woodworking tools.
One possible re-mix would be to use 2 pair of the sets as a hinge for frames made of 2020 extrusions. It can also be used to mount cameras to other surfaces that simply need to be bolted, or even temporarily attached with VHB mounting tape or pads. For that matter it may be handy for mounting studio lights and the like.
As always , feel free to re-mix, or let me know if there is something you would like to see with this.
Odd as it may seem, I'd advise printing along the back, rather than on the base the model looks like it's been oriented. This should allow layer lines to provide greater strength if that becomes needed. I've found that a layer line that's parallel to the 2020 extrusion, is likely to fail.
This was designed in TinkerCAD and my original model there is at https://www.tinkercad.com/things/dlAXZ4ellHl-45-degree-go-pro-mount