Building a Mikrokopter a' la carte (from parts, no MK kit purchase)

[moslow]

WooooWhooooo just got e-mail mine is going out in morning.. They just finished the ARFs I bought the hexa xl and it comes with MK3538 Motor and these motors produce 2200g thrust compared to 820g thrust of the
2827-35 Motor if I read it right, seems like a big differance. Also got the ziggy 10,000 mah monster=2 hyperion 25c 4s 5000 mah with deans parallel cable. That ought to give it a little more fly time especially since I got the new SkyRover SR2 Camera mount System which will carry the larger cameras weight and size. Should be here wednesday...Going to be a long 3 days....lol

 

[Droider]

Little boy waiting for santa eh Moslow... Who's built it?

 

[Bartman]

so, to get things back on topic, eh-hem, it looks like the droidworx AD-8HL is the way to go. Since the topic is about ordering ala' carte, I'm wondering if the frame can be bought in parts, instead of as a kit, since I don't have a camera mount picked out yet and I may not need the standard gear.

 

[FOX222]

Bartman,
What do mean "standard gear"? Are you talking about the landing gear or the electronics? The HL frames comes with the larger landing gear.

 

[Bartman]

I moved this thread to the MRC build threads section as I believe I'm ready to proceed (Thanks for the kick in the butt Mr. Droider!) and intend to document it as a full blown beginning to end Mikrokopter build done ala' carte which just means I'm going to overanalyze every piece for your reading enjoyment before buying anything and will forego the usual Mikrokopter route of buying a complete kit.

@ Fox, some of the camera mounts have the gear built into them, and since I haven't determined which mount I'm going to use, I can't say for sure which landing gear I'll end up with. I really like the flexible gear that Droider has on his quad so I could very well end up with something like that. I've also considered using composite rod with balls on the ends to give flexibility and protection from snags...but I'm getting ahead of myself!

First off, the BRAINS OF THE BIRD, or Bird Brains if you will (Bird Brains!! ha ha ha ha ha) . Mikrokopter, without a doubt. Next question, do I have the fine people at Quadrocopter.us (or NGhobbies.com FWIW) solder my boards for me or do I venture into new territory and do it myself (you can't hear it but my knees are shaking at the thought). I am here for your amusement and to set a good example so I think I'll solder my own.

To complete the bird's brain I'll also need the NAVI board and GPS so I'll see about ordering them at the same time.

Motors and ESC's???!!! Motors probably won't be MK because I want to expand my knowledge base and understand what my other options are. ESC's may or may not be Mikrokopter. MK motor controllers are expensive and the board leaves them very firmly implanted within the copter structure. I could use the MK controllers but without the neat power distribution ring. That would slenderize my electronics stack and putting the ESC's on the exterior of the central frame would make them easier to change and in a better position to dissipate (two s's in dissipate, who knew?) heat.

Frame will very likely be the Droidworx AD-8HL. There's also an AD-8HLE but I don't know what the extra E on the end stands for. I like the simplicity of the tube arms and stout structure but I'm not sure if I'll need the gear or not so I'll leave the final decision for another day. I've got to find me some pennies so I can order the boards and get this adventure started. I also happened to start another project last night that will lead us to a board mascot of sorts but it will take months to do and so I'll leave it a mystery for now.

Thanks for reading.........to the Bartcave!

 

[Droider]

Bart.. The HLE has the extended landing gear, the HL has the standard landing gear. If you went with the AV200 as an example you would need the HLE. Which ever DW frame you got I am sure you would not have trouble selling on the landing gear if you did not use it. BTW the new design of landing gear has been beefed up a tad.

I used pingpong balls on my flexi landers originally but it looked a bit bazaar. I dont think that type of landing gear set up would be strong enough for the weight of a HL Octo.

Why an Octo?

 

[FOX222]

Bart,
I hated the standard PDR also. The layout was cheesy and weak plus it was a PITA to remove a bl if you needed to.
The Octo XL board is a lot better setup as it overlaps the edge of the bl's and the jumper wire is straight through plus it attaches at 3 points instead of 2 making the bl more stable. I have the standard lift Octo but I liked the XL PDR so much I put one in mine. I also found a neat way to make the I2c connections for the Isolator.

 

[Droider]

Fox.. what are those props, and thought you had a gps thingymabob on your GSP board

 

[Bartman]

Dave,
The props look like the three blade ones from hobbyking.
Why an Oktokopter? Primarily for survivability. Yes, a hexa is supposed to be able to survive a motor failure but an Okto can definitely survive and remain somewhat flyable and even controllable on the way down. If I eventually get wedding work and other higher end projects, I want to know I've done everything possible to keep my equipment from landing on someone's head. So an Okto it is.
Gear/frame/camera mount......to be determined but thanks for explaining the HL vs. HLE question I had.
I just got back from getting my commercial insurance finalized and I'm expecting the weather to be good enough tomorrow to hit the road with the equipment and to get some work done. I've got two commercial solar installations to shoot, let's hope for some sun!
Bart

 

[Bartman]

Bart,
I hated the standard PDR also. The layout was cheesy and weak plus it was a PITA to remove a bl if you needed to.
The Octo XL board is a lot better setup as it overlaps the edge of the bl's and the jumper wire is straight through plus it attaches at 3 points instead of 2 making the bl more stable. I have the standard lift Octo but I liked the XL PDR so much I put one in mine. I also found a neat way to make the I2c connections for the Isolator.

Fox,
do the BL's (for those of you that are new to this, BL is Mikrokopter speak for the brushless motor controllers, called ESC's (electronic speed controllers) in other corners of the RC hobby) come with the three prong servo plugs already attached for the I2c isolator wires?
background for anyone considering a Mikrokopter, the I2c circuit is how the flight controller get its motor commands to the BL's which then control the motors. This I2c circuit works great but has a major flaw, one BL failure can render the other motors' I2c signals useless making the other motors all fail simultaneously. There is a circuit board available called an "I2c buffer board" that (I think) individualizes the signal so each BL is only getting the information it needs and can't have that stream of information interrupted by other BL failures. It's cheap insurance against a complete I2c triggered catastrophe. I still need to add this feature to my current MK Okto but just haven't gotten around to it.
I'm not an electronics expert but the above is how I understand this stuff. If anyone wants to expand on it, feel free to.
Bart

 

[FOX222]

Fox,
do the BL's come with the three prong servo plugs already attached for the I2c isolator wires?
Bart

No I added those. The circuit trace for the I2c is visible on the board so just cut the trace right at the esc and then soldered in the three prong header where you are suppose to install jumpers anyway. I mainly did this in attempt to cleanup the wiring some but could also help with trouble shooting if the need arose.

John

 

[Bartman]

Thanks for the pic. Do the plugs extend through the BL's to the underside and get soldered there?
I'm still a bit hesitant to put the BL's under the hood with the other boards especially since MK is now pushing heat sinks for the BL's. So much to consider.

If anyone is surfing through and has a question, feel free to register and ask whatever you want.

Bart

 

[FOX222]

Yes they go through a small protrusion on the PDR and then through the esc at the "C" & "D". The XL PDR has holes that align vertically with the holes in the esc so it is sitting just under the PDR. If you need to remove the esc from the PDR you just heat the pins on one side and push the esc down then the same on the other side. I like it a lot better then the standard PDR plus it allows for two caps on each board (better power handling) and you have 2 circuits for power between the boards (less resistance).

John

 

[Bartman]

that's a pretty interesting evolution of things. did you build out that board or order it ARF'd?

 

[FOX222]

I built it. I had the stock octo PDR in the beginning but after building one for someone else I had to have the XL version. I am about to start a AD-6HL tomorrow for a guy I will take some better shots of the mod for the isolator board.

 

[Droider]

Fox222.. do you know what temp your BL get to fully loaded up?

Bart I am not sure it is so much of a problem if you put them under the hud on the AD8. Have you seen how Sandor at Digitech keeps his cool? His latest video is very good and he addresses cooling of the BL's.

DroidWorx also now do a vented hood

[video]http://youtu.be/7jRXK-JD-gM[/video]

 

[Droider]

Has any one used the SMD Extension board that Sandor talks about in the video?

 

[FOX222]

Fox222.. do you know what temp your BL get to fully loaded up?

No I am not having any issues but I am using the smaller motors so it's not the best platform for comparison. I am starting on a hexa heavy lift today so by the end of next week I can tell you more about temps. We are already getting temps in the upper 80's here so I can get good ideal of how they handle in warmer weather.

 

[RTRyder]

Thanks for the pic. Do the plugs extend through the BL's to the underside and get soldered there?
I'm still a bit hesitant to put the BL's under the hood with the other boards especially since MK is now pushing heat sinks for the BL's. So much to consider.

If anyone is surfing through and has a question, feel free to register and ask whatever you want.

Bart

I thought of using connectors on the BL's for the isolation board leads but went with soldered connections to eliminate a potential point of failure having the second connector. I know that theoretically the Hexa will still fly if a wire popped off and the motor stopped but I have no desire to test that capability for any reason less than an actual component failure in flight, call me paranoid if you like.

That said I can't wait to get the X8 in the air and see how that flys, might just convince me to modify the AD-6 into the same configuration if it works out the way I think it will.

Ken

 

[Stacky]

Ive had 2 motor failures on a hexa and both times crashed. For an experiment I tried to fly my hexa while disconnecting a motor. Tried all the motors and couldnt lift off without flipping no matter which motor I had disconnected. Maybe I should have done the experiment with it airborne but I have yet to be convinced of a hexa surviving a motor failure.