Mobius remote lens' take 2..

sofaspud

Member
Joined
Apr 8, 2013
Messages
60
Reaction score
36
Location
London
Country
United Kingdom
Sorry this is a long post, but hopefully worth a read...

from this original attempt for a twin lens mounting,
https://dashcamtalk.com/forum/threads/mobius-remote-lense-s.5125/

I finally got around to having a more enclosed housing 3D printed by a commercial service.

I was thinking along the lines of a case similar to the ultrasonic sensor cases on older retrofit car alarms. To create the design, I used OpenSCAD, a free 3D design tool. This is great for making geometric shapes, but is more difficult if you want to create more free flowing shapes as you create items by using a construction (text) file rather than a graphical interface. Although it seems daunting, I found it perfect for this project as it forces you to use absolute measurements rather than moving stuff with a cursor.
http://www.openscad.org/

To avoid getting too involved with trig during the design work I created the individual lens housings as shown below.
I still use the narrow (lens A) units, but the case design takes both this & the wider angle versions (lens B & C) using the same principle as the Mobius case(see the piccies below)

23wk5k6.png


From this I then replicated & merged the shapes at the required angles & infilled the gaps to create this:

2jczgus.png


I also included some air slots to get some (limited) convection cooling for the imaging plate. Not entirely sure these are needed as the Mobius case doesn't use such a scheme, plus the lens' are no longer subjected to the heat of the other chips in the Mobius.
I also added a mounting slot to the upper half.

The lens's are mounted at 39 deg from the straight, to give an included angle of 78 deg. This allows a bit more overlap than the metal brackets I used before. I found with the angle used before, something of interest immediately ahead of the car was never quite in full view on either camera. The angle used on this design cures that issue.

The lens' are held in place by the cut out(s) in the design which also clamps down on the lugs of the lens body to hold it securely. 2 of these cut outs are included so I can use A, B, or C len's as I choose, in the same way you can with the Mobius case. I don't intend to use the wider angle on the twin case as it is angled for the narrow lens.

Because of the way the print bureau I used sells 'space' on their printer in defined volumes, I had spare volume with only the twin design included, so had some single lens holders printed as well. I plan to have a play with a single wide angle lens using the single lens cases.

When the design was complete & the printing volume packed full, I sent it of to the print bureau. A couple of days later I got back these:

2j43mef.jpg

vzvqk4.jpg


After 'cleaning' & painting:

ourw4g.jpg


I actually roughed up the surface further with some 40 grit to try & get a texture similar to the plastic moldings used in cars so it would blend in better

The lens is held in place in the same manner as the Mobius case holds them. The ribbon connector sits behind the lens body & the extension cable exits through the slot in the back of the case.
I deliberately made the space for the ribbon connector as small as possible to reduce the size of the case. I was a bit nervous as the ribbon is bent quite severely, but having fitted them carefully it works & has given no trouble for the few days I've been using these. As the cables don't move when installed there shouldn't be any flexing on the bent ribbon so I don't expect there to be any trouble with this.

The 2 halves of the design are secured using #0 self tappers in countersunk holes in the lower half of the case. I also used registration pins in the design to ensure the 2 halves align correctly.
nlprhg.jpg


& a single lens case, B & C type lens's use the forward mounting slot same as the Mobius:
nnpqhg.jpg


Assembled unit, as an indication of scale the squares in the background are 5mm:
6xrvom.jpg



To attach these to the screen, for now I use a simple metal bracket, the mounting tongue is sized to allow a small amount of sideways twist, up & down adjustment is through bending the bracket.
2009udl.jpg


And installed in the car:
2cxybro.jpg


Not really visible due to the reflections on the screen, so in the garage:
5nt3k.jpg

2j46l92.jpg


The Mobius bodies are still in the same location as before, not entriely satisfied with this as one of them can be seen from outside the car as seen in the above pic.
I intend to make some different brackets to relocate them, although I'm limited by the length of the extension cables.
The lens extension cables I hid behind the plastic moulding covering the rear view mirror mounting visible in the following picture

ioktae.jpg



Limitations/benefits/errors:

I already knew the principle of the idea worked from the previous project, so the only concern for this project was the severe bend on the ribbon cable. This proved not to be a problem.
The only change from the previous is there is now more overlap between each lens to better cover the front of the car, as I wanted.
I think these look much more discrete, and so are less noticable from outside.
The lens required re-focussing as I originally had them mounted on the metal brackets using the imaging set screws & so disturbed the focussing when I removed them. I did this once the lens were mounted in the case, but before installation in the car.

The bureau I used uses the sintering method which is basically fusing nylon granules layer by layer. This allowed more complex shapes as the granules support each other during the print.
When I got the prints back, there was a lot of waste to clean out. There is a lot of nylon powder that was not fused & tends to fill any cavities in the items. They do clean out the worst & I could have paid extra & have them clean (wash) them further & even 'polish' them, but chose not to.
Due to the heat involved in the sintering process, I found that if you have a large flat area in the design, then allow greater distance between this & other items in the volume, as the conducted heat semi fuses nearby items. Doesn't fully fuse them, but makes cleaning afterwards more a touch more involved. Things like very small diameter pilot holes in the design are prone to this limit & required drilling out, next time I would make greater allowance for this.

The design I sent off was for the metal bodied lens'. As we now know, the newer FRP bodies are slightly larger. Not an issue for me as the lens' I have are the metal versions, & to fit the FRP will require a little bit of 'fettling' to carve out a slightly larger area. The case walls are thick enough to do this though. If I was to do anything further with these ideas then it is simple to enlarge the cut outs in the design files to suit the FRP lens'
 
Last edited by a moderator:
very nice, but the lens module is getting hot, and you made it from styrofoam.
1. how is it on daily (at least 1 continuous hour of recording) use ?
2. Why not hide the body of the camera behind the sensors so the cameras would not be seen from the outside?
 
very nice, but the lens module is getting hot, and you made it from styrofoam.
1. how is it on daily (at least 1 continuous hour of recording) use ?
2. Why not hide the body of the camera behind the sensors so the cameras would not be seen from the outside?
I didn't make it from 'styrofoam' it's made from Nylon & the temp rating is more than sufficient...
1.
As I pointed out in the post, it is no longer subjected to the heat from the other chips, so will have an easier life. It does not even feel warm to the touch when operating. In the original Mobius design, they use heat conductive tape to transfer heat from the imaging unit to the body, there is no other means of cooling, there is no air flow through a Mobius case (that you could measure) & there are other chips running far hotter causing further heat rise which this does not experience in this design.
2. Again, as I mentioned this is a 'further work to do' & there is a limit due to the length of the extension cables...
 
So much awesome, great work!
 
Nice :)

I wouldent mind a option like this to come with future dual camera on a wire dashcams, then you can use both front and rear camera on front window for a super wide view.
Imagening some form of bracket that would hold both cameras in this manner, and maybe another bracked for that 1 camera forward 1 camera inside the car ( for the cab drivers out there or the avid V blogger )
 
would it be possible for you to provide the CAD files for this. I'm planning to make a 3D holder for my mobius, to the body can be hidden under the upholstery and the lens to be attached via a 3d printed part to the mirror housing as I really want to dether thieves and my windshield doesn't have any black dotting.
my mobius is on its way but I would like to have this done before it comes as the 3D printer technician will go on holiday soon.
 
We have free 3D printers in public libraries, it would be nice to try one.
Desperately need something to print;)
 
We have free 3D printers in public libraries, it would be nice to try one.
Desperately need something to print;)
:cool:
All ours does is free books (I also get my Ordinance Survey maps when we go on holiday)
 
Here is some 3D model for mobius, i think it's possible to extract one or two mobius lens holder from that plan using CAD editor, legal issues i don't know, model is freeware though.
http://www.thingiverse.com/thing:667793
 
Thank you all. In the end I created my own (took me some time as the printer has a tendency to deform the part a little). The lens type C sits snuggle in there and you can even put the cap on.
Used M3 screws to attach the parts together.
If anyone need them they are available here: https://www.youmagine.com/designs/mobius-lens-c2-holder
sample video (sorry for the romanian, it was meant for a romanian forum):


camera was mounted on a BMW e46 from 2001. the holder under the rain sensor housing (didn't fit inside) and the camera above the rearview mirror for easy access to the buttons. Use Nylon or ABS if you're doing simiar projects as PLA will deform at 40+ degrees celsius (sunny central/southern european weather).
 
Last edited:
Is there a way to get a really long lens cable? Like 5 or 10 feet? How?
 
Any similar cameras able to do this? I want a 4-6 channel setup with the brains in the glovebox.

often used like this for rear cams, not something with multiple cams unless you get into the truck type setups but the cameras are quite large for those
 
Back
Top