Building from my previously published 215 Hopper I designed the 215 Hopper FPV. This new model offers significant durability improvements, it can now sustain a heavy grounding without terminal damage, critical for FPV (particularly whilst learning). I won't claim that it is as durable as a carbon plate design but I am now happy that for someone looking to build from scratch this will be a suitable option. The camera pod is perhaps the least durable part of the design however I am still flying with the first one I printed and it has served its purpose protecting the flight cam. Occasionally in a particularly awkward crash the camera will pop out (exactly how I'm not sure?!) so always check before walking away from the crash site. I do intend to upgrade the camera mounting at some point, it will appear here as soon as that happens.
My blog entry about this release can be found at: http://andrewtaylor.net.au/2016/07/03/215-hopper-fpv-rebuild
Another blog entry containing a lot of still relevant build tips for the original 215 Hopper can be found at: https://andrewtaylor.net.au/2016/03/26/215-hopper-build/
The full history of the 215 Hopper can be found at: https://andrewtaylor.net.au/category/215-hopper/
Feel free to order the required PCB (215H_PDB Rev 2.brd) from any fab shop. I find the value (particularly for a board this large) offered by http://dangerousprototypes.com/store/pcbs hard to beat.
All the 3D printed parts are printed in ABS with a 30% infill, 3 outlines, 3 solid bottom layers and 4 solid top layers. Colour is unimportant but I find it looks its best if the frame parts are a bright colour, as seen here in orange and the accessory parts are black.
If your printer is well calibrated then minimal post processing will be required. I usually take the back edge of a razor blade and scrape all my edges to smooth them out and remove any over extrusion that has occurred at the bed level. This can even be taken so far as to remove the visible layers from the 3D contoured parts such as the vTx pod and camera housing. I will also often use a piece of silky cloth to apply acetone to the visible surfaces resulting in a smooth, clean look.
Holes are intentionally left on size in CAD, rather than making allowances for fitment. This means that wherever there is a fastener hole you should drill them out for a nice fit. 2mm for M2's, 3mm M3's and 5mm where the aluminium standoffs are used. I find for blind 5mm holes a drill bit with the tip ground flat is the easiest approach to ensure a clean hole.
The other area where tight fits are required are the lobes on the top and bottom of the frame sides which snap in to the top and bottom plates. If they won't sit in place then the joining faces between the tube clamps and frame sides should be shaved down. The lobes themselves may also need to be tidied up if they won't fit into the plates in isolation.
Whilst not strictly necessary I solvent welded the 3 parts of the camera mount together (parts 131, 132 and 133). Durability has exceeded my expectations so that is probably a worthwhile step to take.
The 215 Hopper FPV is designed around a fairly specific set of components. This is not to say that other parts won't work on the frame but rather that the positions and space allocation work best with what I have used. My recommended build uses:
- DYS 1806-2300kV motors
- 18A ZTW 18A Spider series Opto ESC's
- Naze32 Rev 6
- 25mm Plastic housing FPV camera such as the HS117 or HS1189
- Lumineer TX5G8 Pro power switch vTx
- FrSky X4R-SB receiver
- Pololu 5v converter
- 5cm 90° bulkhead SMA extension
- 12mm x 10mm x 500mm carbon fibre tube
You will also need the following fastener:
- 18x M3x15 Round threaded standoff
- 2x M3x20 Round threaded standoff
- 40x M3x8 Button head socket screws
- 4x M3x10 Nylon screws
- 8x M3 Nylon nuts