Waterproof Raspberry Pi Camera Pan Tilt Mechanism

Fully weather-proof pan and tilt camera bracket controlled by bowden cables suitable for MIPI cameras as used by Raspberry Pi . The cables can be controlled by linear actuators safely hidden away under a water proof cover. Project sponsored by https://www.pcbway.com/ .. some tight tolerances are required for this project, which this company can handle well.

Normally camera pan / tilt systems have motors attached to the moving parts which makes weather-proofing very difficult or very expensive. With this design has the electric actuators are hidden away remotely under a weather proof canopy or in an enclosure thus reducing the complexity and cost of the mechanism. Torsion springs act against the cables as normally they only operate in a pull mode.

Additionally, there is a square IP68 enclosure for the camera itself. The 16mm video ribbon comes out through a 25mm gland with a slitted blank rubber grommet inserted ensuring no moisture can get in.

Other than the enclosure, the springs, a few long 5mm bolts, a 5mm circlip and the bowden cables, everything is 3D printed in SLA resin for under $60.

1. Get the 3D parts built using these files: CAD files: https://github.com/paddygoat/Waterproof_camera_pan_tilt_bracket. Everything is standard PLA except for the swivel connector, which is stainless steel.
2. M5 x 70mm bolts x 2 of
3. M5 x 40mm CS bolts x 4 of
4. M5 x 25mm CS bolt x 1 of
5. M5 nyloc nuts x 7 of
6. Bowden cables, 1.5mm + sheath x 3m
7. Cable end lugs OD 5mm x 7m x 4 of
8. Spring, 2mm THK, 7 coils, 90 degrees x 1 of
9. Springs, 1.5mm THK, 4 coils, 180 degrees, 2 of
10. Hammond 1554B2GYCL Watertight PC Enclosure Clear Lid 65 x 65 x 40mm Grey Code: 30-4604 x 1 of
11. 500mm camera ribbon cable
12. 20mm cable gland, 1 of

CAD files: https://github.com/paddygoat/Waterproof_camera_pan_tilt_bracket

I bolted the assembly onto a pallet and weighted it down to ensure it remained stable during testing. Although the final machine will use linear actuators, I simulated that movement by using mole grips to operate the cables. This setup allowed me to verify that the mechanism moved properly across both the pan and tilt axes. During the test, the pan-tilt worked smoothly, even when operating both axes simultaneously.

I found that the mounting and length of the cables were critical factors. The initial 200 mm cables had significant internal spring tension that interfered with the pan movement. I determined that increasing the cable length to at least one meter for the final installation would provide better flexibility. I also discovered that by orienting the cable sheath carefully, I could actually use that natural spring action to help the mechanism return to its default position.

Selecting the right springs required a lot of trial and error from a large variety of sizes. I found that overpowered springs put too much stress on the components, while springs that were too light couldn't overcome the cable friction to return the camera to center. This was particularly important for the tilt pin, which I previously found was a point of failure. To solve this, I used 3D-printed parts from PCBWay that included a small center hole in the pin. I reinforced the pin by sliding a 2 mm spring steel rod into that hole, which prevented it from breaking under the tension of the springs.

For weatherproofing, I used an IP-rated box for the camera section. I identified that the ribbon cable was somewhat flimsy for industrial use, so I planned to add a protective sheath and seal the cable gland with resin to make it fully waterproof. The 500 mm ribbon provided enough length to pass through a mounting surface, allowing the Raspberry Pi and the actuators to be housed safely underneath a panel, protected from direct rain. After these tests, the mechanism proved it was ready for final mounting with longer cables and dedicated actuators.

To put this together, we start with the base disc. I had this part 3D printed with a tiny 2 mm hole running all the way through the center pin. I slid a matching spring steel pin inside that hole to reinforce it, which is really important because the plastic alone might not handle the stress. I got these from PCBWay since they can handle those really tight tolerances.

Next, I dropped a nyloc nut into the hexagonal slot on the assembly. It’s a bit of a tight squeeze, but that’s the nice thing about plastic—you can get everything to fit perfectly. I kept the control cables attached from my previous test, even though the ends were a bit frayed from the mole grips I used. These cables have small metal lugs on the ends that are both screwed and soldered on so they won't budge. I also included an extra spot for a counter-cable, just in case it’s needed later to balance things out.

I slotted the two main pieces together so the pin can move freely in its track. To hold them, I used a 5 mm bolt that is 25 mm long. I made sure not to over-tighten it; you want it snug enough that there isn't any wobble, but loose enough that the discs can spin without too much friction.

To connect the cable to the pin, I used a stainless steel 3D-printed part. I tried plastic for this before, but it snapped almost immediately. I had to do a little bit of filing on the metal to make sure the cable lug could rotate inside it. If it can’t rotate, the cable might bend and snag. Once that was ready, I pushed it over the pin and added a heavy-duty spring. This spring acts against the pin to provide tension. It's a bit fiddly to hook the long arm of the spring over the lug, but once it clicks into the little slot on the pin, it stays secure.

For the tilt part of the mechanism, I used a longer 70 mm bolt and two more springs. These springs sit on their backs at either end of the bolt. I secured it all with another nyloc nut, keeping it just loose enough to move. This part takes a bit of force to push back, which is exactly what we want for a steady camera.

The camera itself goes inside a waterproof, IP-rated box. I used a 3D-printed bracket https://github.com/paddygoat/Waterproof_camera_pan_tilt_bracket/blob/main/CAD_files/rpi_camera_mount_03-Cut028.3mf to hold a Raspberry Pi AI camera inside the case. It’s important to keep the camera lens very close to the clear plastic lid to prevent any weird glares or blurry spots from dust or scratches on the outside surface. To keep the whole thing bone-dry, there's a rubber O-ring on the cable gland and the inside of the gland can be filled with epoxy resin.

The 500 mm ribbon cable gives us plenty of slack to reach through a mounting surface to the Raspberry Pi underneath. This way, the Pi and all the electronics stay protected under a panel while the camera sits outside doing its job, unaffected by any rain. The whole design is pretty beefy—it’s built to survive a knock from a stray 3" tree branch!