Macsgrafs
Active Member
Shawn, how does the MK power loop thing work, surely both thier power rails are a loop?
Ross
Building a Mikrokopter a' la carte (from parts, no MK kit purchase)
- Thread starter Bartman
- Start date
Shawn, how does the MK power loop thing work, surely both thier power rails are a loop?
Ross
Bartman
Welcome to MultiRotorForums.com!!
Arms and ESC's
Wires are run under the arms to make maintenance easier. Electrical tape holds the wires and the ESC's in place on the arms. The yellow tape is the front arm. This layout isn't typical for a Droidworx AD-8 but I wanted the +8 layout for ideas I'd like to test later on.
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Wires are run under the arms to make maintenance easier. Electrical tape holds the wires and the ESC's in place on the arms. The yellow tape is the front arm. This layout isn't typical for a Droidworx AD-8 but I wanted the +8 layout for ideas I'd like to test later on.
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Bartman
Welcome to MultiRotorForums.com!!
I finished assembling the averticalview.com camera mount a few days ago and had to come up with a way to mount it. by itself it had a tendency to lean left or right and that would be worse as the cameras got bigger so I had to drop it down a couple of inches and find a way to make it fairly rigid to the frame so it wouldn't rock. In another thread I said motion can't be controlled by some stabilizing force then it has to be constrained. Since DennyR is exploring the world of completely decoupled mounts and heli's I thought I'd make the mount fairly fixed to the frame using a 2"x2" balsa block, a 1/8" aluminum bearing plate to keep the balsa from crushing, and long 5mm screws that go through the frame and arm mounts to the top side of the center frame. I've seen Gopro cameras mounted to frames with velcro and the results have been surprisingly good so I thought I'd lock everything together with minimal vibration isolating materials and see how it works. the mount has two Hitec 7985 servos so we'll also see if the digital servo route is all bad or not.
I also replaced some of the flat G10 pieces with 1" square aluminum tubing since it fits perfectly and is more rigid. There are also two short pieces of small aluminum angle that are keeping the mount's arm from twisting. The goal here is to have zero free movement of the mount other than what can be controlled by the stabilization.
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I also replaced some of the flat G10 pieces with 1" square aluminum tubing since it fits perfectly and is more rigid. There are also two short pieces of small aluminum angle that are keeping the mount's arm from twisting. The goal here is to have zero free movement of the mount other than what can be controlled by the stabilization.
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Bartman
Welcome to MultiRotorForums.com!!
Ross,
To be honest, I couldn't get the ESC's to do anything functional without the motors attached so I made the power harness, wired the ESC's to the harness, then soldered one motor wire per ESC. I then went one by one to each motor/ESC and connected the other two motor wires with alligator clips, plugged the ESC into a receiver and the power harness into a Lipo to see which way the motor spun. If it was backwards I just switched the two loose wires and finished solering and mounting everything. Once all eight motors were wired I went back and used an ESC programming card to set up each individual ESC's settings. It was more work than I expected but I saved about $600 over the MK BL's and power ring.
It would have been helpful if I took the time to wire a switch so I could just turn the battery power to the harness on and off as I set up each ESC rather than having to plug and unplug the Deans connector.
We'll see in the coming weeks how it flies. I may get a first flight in tonight just to pop its cherry and get the Navi stuff, camera, and wireless video stuff into the mix next.
Bart
To be honest, I couldn't get the ESC's to do anything functional without the motors attached so I made the power harness, wired the ESC's to the harness, then soldered one motor wire per ESC. I then went one by one to each motor/ESC and connected the other two motor wires with alligator clips, plugged the ESC into a receiver and the power harness into a Lipo to see which way the motor spun. If it was backwards I just switched the two loose wires and finished solering and mounting everything. Once all eight motors were wired I went back and used an ESC programming card to set up each individual ESC's settings. It was more work than I expected but I saved about $600 over the MK BL's and power ring.
It would have been helpful if I took the time to wire a switch so I could just turn the battery power to the harness on and off as I set up each ESC rather than having to plug and unplug the Deans connector.
We'll see in the coming weeks how it flies. I may get a first flight in tonight just to pop its cherry and get the Navi stuff, camera, and wireless video stuff into the mix next.
Bart
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Bartman
Welcome to MultiRotorForums.com!!
well, it flew tonight but only for a few seconds due to an uncontrollable yaw to the right. trying to lift off with the stick way left didn't change anything so i'll have to do some review and see if anything was done wrong.
hmmmm, good time for the confused smiley,
hmmmm, good time for the confused smiley,
Bartman
Welcome to MultiRotorForums.com!!
i think i've discovered my problem, i wired my motors to turn opposite to the Okto2 diagram so my center #1 prop is turning clockwise as viewed from the bottom instead of counter-clockwise. A quick guess as to the fix seems to be that I'll have to go into the mixer tables and make all of my positives negative and all my negatives positive. I'll sleep on it but I think that that would have the effect of reversing the controls to match my directions of rotation.
Anyone have an Aye or Nay to this?
Thanks,
Bart
Anyone have an Aye or Nay to this?
Thanks,
Bart
Dave, do you have some photos of this?
Macsgrafs
Active Member
This is starting to sound like fun Bart
I'm actually getting worried myself, because you have so much experience with MR aircraft & I have none....what chance do I stand to get my octo off the deck this side of xmas I wonder Stick with it mate, I bet you have it sorted in no time.
Ross
I'm actually getting worried myself, because you have so much experience with MR aircraft & I have none....what chance do I stand to get my octo off the deck this side of xmas I wonder
Stick with it mate, I bet you have it sorted in no time.Ross
Bartman
Welcome to MultiRotorForums.com!!
It flies! With the props turning opposite to what the firmware was expecting, the yaw response was reversed. Changing the negative yaw values to positive and vice versa in the Mixer Table fixed it. I've posted in another thread about a slight galloping motion that I'm seeing so I'll have to work that out but I'm going to go ahead and mount the Navi stuff and the rest of the camera mount gear at this point. It's also time to get the dome fitted and painted. should i do zebra stripes or ladybug dots?
Droider
Drone Enthusiast
Bartman
Welcome to MultiRotorForums.com!!
update finally
i had the new okto flying and wasn't happy with the slight wobble it had. it was fine for fun flying and photos but for video it wasn't acceptable. played with it a bit but i just don't have the time to futz with it so i pulled the esc's and ordered an assembled okto XL power ring with 8 MK BL''s. wired it up and it blew three bl's. sent it back, got another that had been built from my eight original BL's and hooked it up only to get an I2c error. the dreaded I2c error is why I tried the original ESC's to begin with. how ironic that I'm now considering going back to the ESC's and I2c converter just so I can get flying again. I've soldered, unsoldered, soldered, unsoldered eight sets of motor wires so I'm a bit pissed right now that I just inhaled more MK smoke. that's right, the #3 bl which was originally indicating a fault blew a black square thing (mosfet?) while i had power on it to check if #2 was still indicating a fault.
dead in the water and a bit frustrated. especially because i have a camera mount that is yet to show its worth after extensive customization.
argh!!!!!!!!!!!!!
bart
i had the new okto flying and wasn't happy with the slight wobble it had. it was fine for fun flying and photos but for video it wasn't acceptable. played with it a bit but i just don't have the time to futz with it so i pulled the esc's and ordered an assembled okto XL power ring with 8 MK BL''s. wired it up and it blew three bl's. sent it back, got another that had been built from my eight original BL's and hooked it up only to get an I2c error. the dreaded I2c error is why I tried the original ESC's to begin with. how ironic that I'm now considering going back to the ESC's and I2c converter just so I can get flying again. I've soldered, unsoldered, soldered, unsoldered eight sets of motor wires so I'm a bit pissed right now that I just inhaled more MK smoke. that's right, the #3 bl which was originally indicating a fault blew a black square thing (mosfet?) while i had power on it to check if #2 was still indicating a fault.
dead in the water and a bit frustrated. especially because i have a camera mount that is yet to show its worth after extensive customization.
argh!!!!!!!!!!!!!
bart
Bartman
Welcome to MultiRotorForums.com!!
Continuing right along, after having had two bad experiences with MK BL power rings I decided to go back to the ExceedRC ESC's since I knew I could at least fly with them, do photography, and continue to work on my camera mount. I don't what is different this time around but the heli is flying much much better than it did the first time. In discussing a handful of options with RTRyder I only changed the props to a set of Graupner 11x5 E-props that I had from another project. It's a night and day difference over the original experience. I haven't tried the GPS and Navi modules yet so I can't say if they would effect anything or not. I'm wondering if there's anything different in my setup that changed the flying qualities???
I've said it, DennyR has said it, I'm sure others have said it, these things fly better with props that are loaded up with weight. My current Okto can't be a whole lot heavier than my original MK Okto 2 but I'm flying 12" props instead of the original's 10" props. That's a lot of prop for a little increase in weight. Maybe with a bigger Canon camera I'd need the bigger props but I just had a really awesome flight with the MK FC, Timecop's I2c converter, ExceedRC 30A ESC's, and the Graupner 11" props. On the camera mount I had a GoPro and will take a look at it and maybe post it later.
I'm dumbfounded (in a good way).
Bart
I've said it, DennyR has said it, I'm sure others have said it, these things fly better with props that are loaded up with weight. My current Okto can't be a whole lot heavier than my original MK Okto 2 but I'm flying 12" props instead of the original's 10" props. That's a lot of prop for a little increase in weight. Maybe with a bigger Canon camera I'd need the bigger props but I just had a really awesome flight with the MK FC, Timecop's I2c converter, ExceedRC 30A ESC's, and the Graupner 11" props. On the camera mount I had a GoPro and will take a look at it and maybe post it later.
I'm dumbfounded (in a good way).
Bart
My Y6 flys like crap on APC props using the same I2C converter and motors you have, wobbles badly as soon as it leaves the ground. Changing to 11 x 5 Graupners cured about 85% of the wobble and tweaking gyro settings got another 10 or 12%, just a tiny bit of dialing in left before it flys as good as its going to get.
The problem I believe is this, with the lower KV motors and props that take a big bite of the air they can't respond quick enough to speed change commands. Swapping to the stiffer and narrower blades of Graupner props lets the motors speed up quicker so they respond better to the flight controller. That's my theory anyway and it seems to be what's happening...
Ken
Bartman
Welcome to MultiRotorForums.com!!
ken,
i'm wondering if the wobble isn't undercontrolling but overcontrolling. maybe the bigger props and motors aren't working hard enough and the control commands are actually being sent with too much oomph and making the copter wobble from an excess of control.
hmmmmm???
whatever it is, i've wasted a lot of time and money in the last two weeks dealing with this!!
bart
i'm wondering if the wobble isn't undercontrolling but overcontrolling. maybe the bigger props and motors aren't working hard enough and the control commands are actually being sent with too much oomph and making the copter wobble from an excess of control.
hmmmmm???
whatever it is, i've wasted a lot of time and money in the last two weeks dealing with this!!
bart
If it was overcontrolling that means the motors would responding too fast and in that case larger props would slow it down and tame the wobble, clearly that isn't happening here.
Ken