Robust Flight Camera Pan Assembly for FPV Flying Wings

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This is a fairly robust yet reasonably lightweight pan assembly for a FPV flight camera. It was designed and intended for a Chimera Flying Wing for FPV, but can certainly be used for other craft as well. Here's a flight video of it in action: https://www.youtube.com/watch?v=bapxTDwmhos Required Parts List, in addition to the (4) printed parts: (1) Turnigy TGY-R5180MG 180 Degree MG Analog Servo. http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=65966 (1) Surveilzone HS1184 28x28mm Sony Super HAD CCD 600TVL Mini Camera http://www.surveilzone.com/28x28mm-Sony-Super-HAD-CCD-600TVL-Mini-Camera-Alloy-Case-g-1380 (4) M3 nylon lock nuts (4) M3 bolts (4) Small screws to attach the servo horn to the top pan assembly. I cannot guarantee that this pan will work with other servos. I do know it would need modifications to accomodate the RMRC 260 deg servo. I highly recommend the above Turnigy servo as it's inexpensive, provides a smooth pan between steps, and has about +/-130 degrees of rotation if the transmitter endpoints are set to +/- 125% (800 to 2200us pulse width). I tried the RMRC 260 deg servo, and while it had better torque, it was slower and the steps were not nearly as smooth. As far as the camera, others will certainly work, but I selected this one because it uses the same sensor as the PZ0420 which works very well for FPV, but it's smaller and has a fairly lightweight alloy case which is great for minimizing UHF interference. Here are the STL files for the pan assembly. There are 4 parts: The plane "base" mount. It's designed to be printed with the captive nut holes facing upwards. Use M3 nylon lock nuts in this. I put in a drop of CA glue to hold them in place. This part gets physically bonded to the plane after cutting out foam in the nose. I used hot glue, but contact cement like uhu-por might be even better. A servo shim plate. It's thin and does what you think it does - acts as a shim between the plane base mount and the base of the actual pan assembly. The lower part of the pan assembly. The upper pan assembly. This is intended to be printed with the cylinder groove upwards. I printed everything in 0.2mm layer height in ABS. I wouldn't recommend PLA since it warps easily in a hot car (been there, done that with a 3D printed tricopter...it's not worth the risk). The parts fit very snugly and you'll probably need to file and/or sand them down to get a good fit between the upper and lower pan assemblies. You'll probably want to sand the top of each race flat as well. Once it rotates somewhat freely, clean away the excess grains of plastic with isopropyl alcohol. Then, use synthetic grease in the groove. I use Tri-flo. Again, it should rotate 360 degrees smoothly and without binding. If I recall correctly, the total weight of the pan assembly (minus the servo and the camera) is 35g. If you want to save weight, you can forego the lower plane mount piece and shim, and screw in the servo to the lower pan assembly using screws through the servo ears. That will reduce the pan assembly weight to around 25g. I like the option of being able to remove the pan assembly in case it breaks, though, so it can be replaced without re-gluing it to the plane. A bit of background: I designed this because I wasn't satisfied with any of the inexpensive pan systems I found on the market, which typically bear the entire weight of the camera on a servo horn. Such a design, while lightweight, not only results in camera vibration, but the mechanism is prone to breaking where the horn is attached to the servo during a rough landing or a crash. This design is intended to minimize the stress on the servo axis and horn through the use of the larger diameter cylinder which tracks in a groove. The design isn't perfect, and I haven't crash tested it yet, but it certainly feels like it would hold up better. An improvement would be the addition of bearings, but honestly, I'm not sure it needs it as it moves very smoothly after sanding down the surfaces and applying synthetic grease. Print Settings Printer: MendelMax 1.5+ Rafts: Doesn't Matter Supports: No Resolution: 0.2mm or smaller layer heights Infill: 30% or higher Notes: Strongly recommend ABS or a high glass transition plastic. You don't want to use PLA as it could warp in a car on a hot day! Post-Printing I strongly recommend building the entire assembly before bonding the bottom plane mount to your RC aircraft. Assembly Instructions: Clean up the printed parts with a hobby knife. There will likely be an unwanted bridge in the lower pan assembly where the servo body passes through - cut this away. Sand down the top and bottom pan cylinder races flat, and then the grooves until binding no longer occurs. I allowed for 0.1 or 0.15mm gaps between the top and bottom pan assemblies in the design. The fit is intended to be tight. Hand files from Harbor Freight work very well for removing excess material from the grooves. If everything moves freely, clean the grooves with isopropyl alcohol, dry, and add some synthetic grease (e.g. Tri-Flo) to the appropriate surfaces. The pan should now "glide" on the grease as it rotates. Install the (4) M3 nylon lock nuts in the plane base mount. I put in a drop of CA glue to hold them in place. Test fit the servo in the lower pan assembly. The ears should sit nearly flush to the bottom (might be a 0.5mm gap). Test fit the servo in the shim and lower pan assembly. Install the 4-ear servo horn in the upper pan assembly. You'll need to cut the longer ears down to the length of the smaller ones. Use some small screws that can bite into both plastics. The heads of the screws should be on the top of the flat surface. For additional peace of mind, use a little bit of adhesive (although I didn't). Test the entire assembly using a servo tester. Center the servo using the tester and attach the horn screw. You might want to use a drop of blue loctite to keep it from backing out. Install the "U" mount to the top of the pan assembly. I used small hex bolts (M1.5 or M2, can't recall) and nuts. Locite should be applied here if using fasteners. Fasten together the lower 3 layers with the M3 bolts. Everything should be together now, minus the camera. Attach the camera to the metal "U" mount using the screws that came with the camera. I highly recommend using washers to increase the surface area grip to prevent the camera from undesired tilting while in flight, and also the use of blue locite. You'll likely want a 5 to 10 degree down angle for the camera. Let the locite dry, and make sure everything works! If necessary, cut cavities into the R/C craft. Make sure to cut one for the servo, too. Do a test fit and check for clearance at all pan angles. In my Chimera, I simply used a sharp hobby knife. Bond the lower plane mount bracket to the plane (or other R/C craft). To prevent seepage of adhesive into the multiple layers, you might want to remove the (4) M3 bolts and just bond the plane mount piece. I recommend either hot glue or contact adhesive such as UHU-POR. I strongly recommend using some sort of strain relief for the video feed cable. You don't want stress on the non-locking connector that most FPV cameras have. I simply cut a 1" mounting block down to about 3/4" on one side, attached that to the back of the camera, looped the video feed cable in a "U", and zip-tied it. That way, when the camera pans, the stress is on the zip-tie point rather than the connection point. There I'm sure that there are better ways to do it, though, so I'll leave it to you folks :). Enjoy, and happy FPV'ing!