Thursday, May 21, 2015

Emax250 Full CF : the learner FPV rig

This is my learner FPV rig, Its a EMAX Nighthawk, or similar knock off. Its proper carbon fiber. I also ordered some extra arms and base plate for when i crash and wreak stuff.

This is the old donar ZMR LOS play thing. DYS1806, 5040s emax 12amp esc and a naze32 acro.

Time to strip the ZMR down

To give myself some extra room I used 5mm ally standoffs instead of the 3.5s provided.

The PDB was bolted to the underside of the middle plate.

Secured in, Time to test if the bottom plate fits on.

Nice close fit, but plenty of space for airflow.

The wire loom octopus now needs a good tidy up. The pdb has three JST connectors, one for rear LEDs, power to the vBat on the Naze32 and one for the video transmitter. 

Bottom view all now nice and tidy.

I also printed some arm protectors, very basic. We will see how well they last. There are 2 bolts that hold the protector on and bolt into the motor. The other 2 are recessed and bolt directly to the arm and motor. Should be good enough to stop gravel rash.

Bottom, middle and arms mocked up ready to clean up the wires.

Biggest job is to clean up the ESC leads that are miles to long. I cut and re-soldered the connectors.

Much cleaner now. I also used heat shrink to add more protection from rubbing on the carbon plates.

The Video transmitter was proving hard to mount. I designed a 3D printed case that I could then double sided tape & zip tie to the frame.

A quick test for its location. I also printed a lid, but forgot to leave a hole so I could change the frequencies. I will print another one that has a hole in the right place.

The case also has some holes to allow for airflow to keep it cool. I hope it will be enough.

I also got a camera mount design off thingiverse and modified it to fit the small gap that between the middle and upper plate. The camera is held with a zip tie and this one is angled at about 10 degrees. Plenty for a learner !

This was double sided taped to the frame and ziptied.

The next challenge was to mount he DR4II, Same issue, it was hard to find a good mounting location. So I made a quick 3D case for it as well.

Finished case, The D4R will held in place with a ziptie.

Time to mount the case in the frame and secure with a ziptie.

Nice and tidy .. and secure.

next was to make up the video camera to transmitter harness. I got this camera off Banggood. I came with is own small voltage regulator inline so I just need to feed it 12v.

I spliced the video transmitter power and video in to a cable that Ts off the the transmitter and is powered off a JST connector. This way I can easily power on/off the video system as required. all from a 12v input.

Time to mount the video transmitter. 3M double sided tape and a couple of zip ties/

All mounted and the wire harness all plugged in.

I also hot glued the joint for extra strength,

Next I want a better solution that just a dangling power cable for the battery lead. I came up with a simple XT60 holder that I could bolt to the frame.

I simple secure battery connector.

Top down look on the 90% middle deck.

Next I made a plastic core flute tray to fit between the ESCs and the bottom plate. This stops and dew / water / grass for getting in there easily and with the tightish fit helps hold the ESCs firmly in place.

Nearly all done.

Top plate on, zipties and heat shrink for the receiver antennas, this little learner FPV rig is now finished.

So the finished ALW is 378 grams, not to bad. I do still have to design and print a rear light bar for it, so add another 15-20 grams.

Here it is next to its acro brother.

Time to get sometime and go learn to fly FPV.