New Y6 Tri-Trooper 900mm & Pixhawk

[jfro]

Decided to try a y6 with 400kv motors and my Pixhawk. I'm taking the Pixhawk off my development quad as it's earned my respect. Replacing the Pixhawk with the new SuperX MiniX. Give that a try.

I've bought a kit with 30mm CF arms which is a little out of my DIY mentality. I've been using rectangular aluminum arms and loving them. Should be a 2-4 hr build and then go fly. Going to use KDE 3520 motors and probably start with 14 or 15" props.

Will start with a 3 axis gopro, then maybe try a light weight 2 or maybe 3 axis gimbal for something like a gh2 and down.

If I don't like this, it will turn into a flat hex. Should be fun...
Y6 Tri-Trooper 900mm should be here for a weekend build!

 

[SamaraMedia]

Going to be following your build jfro, just tore down my DIY square aluminum armed quad to transform into a Y6. Going about the same route, start with a H3-3D then maybe the Quadframe V2 three axis just bought, should be a good winter project. Either going with NAZA or SuperX.

 

[jfro]

I was going to build my own frame with the Vulcan aluminum arms (which I am really liking) to maybe going with Quadframes y6. Then I saw the Trooper with 30mm CF arms and figured why not. Also the fact that is't 900mm and I can cut it back a bit when I find the sweet spot for props and the max weight I'd carry.

I was originally thinking transferring my Naza or SuperX. SuperX is being wasted on a quad as I paid for the 8 motor version. Decided against it (although I may try later) because of my inability to get it working the way I wanted on my x8. Naza v2 is currently on my X8 and flies great. The only reason I'd take it off that is if I had something better as there is still always the worry about a fly ways in the back of my mind. I want to get some flying time on my Pixhawk, so it wins for now.... GPS locks quickly which is a good thing for winter flying....

I may try the new SuperX MiniX on the Trooper sometime, but will wait a few months to make sure it's stable. Be interesting to see if they have improved their co-axial setups.

I'm guessing I'll probably lengthen the landing legs. I like to drop my camera a little lower plus have a few inches clearance as I launch in the grass alot.

Am looking forward to seeing how a y6 flies..... If I don't like it, I'll try a flat hex with the motors. Frame should be easy to sell. Keeping my fingers crossed I get everything before the weekend. Snow is holding off and Sunday looks promising as a flying day with moderate winds and no rain or snow.

 

[jfro]

Have another day or two to decide, but am having 2nd thoughts on Pixhawk. Looking at power supply for 6s batteries and getting nervous. I was going to just put 5v onto the output rail, but then read this warning ....

It is dangerous to power the Pixhawk only from the servo rail, especially with digital servos. Servos may cause voltage spikes (as shown on illustration below that shows the servo rail voltage on an oscilloscope when a single digital servo attached to a Pixhawk is moved rapidly ). The key thing is that the digital servo causes the voltage on the rail to rise above the critical 5.7V level. Above that level the Pixhawk power management will cut power to the FMU and the Pixhawk will reboot. If that happens when flying you will lose your aircraft.

I'm not running any Digital servo's as far as I know, so I don't know if power spikes are a big issue. I do know I ran my 4s quad on 5v rail when I blew the power module. Maybe 8-10 flights for a total of 2 hours max...

Will spend more time reading about the larger power modules. Wish 3dr would just sell the frigging things and say this is for these esc's/motor, part b is for these esc's /motors, and part c is for these. Then tell us what to do with the pixhawk settings. I know I've read what to do on the internet, but remember giving up thinking it was to much to figure out for the non electrician.

ECalc says at max I'm pulling just under 30amp with 645 watts per motor.

Anyway, I am open to suggestions!

 

[Bartman]

we ought to figure out how to correctly gang two buck converters together so that we can make a simple and inexpensive power regulator that has redundancy and smooth output built into it.

if I had to guess I'd say we'd need two buck converters set to 5V with zero ohm output diodes so power can't feed backwards through them and capacitors on the output to smooth out their output voltage. an LED on the output of each would be handy too so we can tell if one or the other failed.

am i close? anyone know enough to diagram this out so we can build a few and use them?

my big hangup on voltage regulators (aka BEC's) is that one by itself isn't a safe power source for a flight controller, IMHO.

 

[Bartman]

i'm really itching to try the NAZE32 flight control board and the Pixhawk after all of the talk around here lately about those two.

i'm roughing out a new A2 XY4 quadcopter but it might be my last DJI build for a while in order to try other stuff

 

[jfro]

I found a redundant diagram for two 5 volt's going to the rails on the pixhawk. I'll go take a look. I've been using buck converters for everything for about 5-6 years with no issues so am comfortable with them. I'll go see if I can find it again.

 

[jfro]

this is beyond me. Maybe it will help.... http://drones.webstanz.be/blog/pixhawk-flight-controller-power-recommandations

 

[Bartman]

jfro,

i'm going to start a new thread about this in the homebrew electronics area. the diagram at the bottom of that link is basically what we're talking about but LED's and capacitors may make it better and more useful.

Bart

 

[R_Lefebvre]

Have another day or two to decide, but am having 2nd thoughts on Pixhawk. Looking at power supply for 6s batteries and getting nervous. I was going to just put 5v onto the output rail, but then read this warning ....

It is dangerous to power the Pixhawk only from the servo rail, especially with digital servos. Servos may cause voltage spikes (as shown on illustration below that shows the servo rail voltage on an oscilloscope when a single digital servo attached to a Pixhawk is moved rapidly ). The key thing is that the digital servo causes the voltage on the rail to rise above the critical 5.7V level. Above that level the Pixhawk power management will cut power to the FMU and the Pixhawk will reboot. If that happens when flying you will lose your aircraft.

I'm not running any Digital servo's as far as I know, so I don't know if power spikes are a big issue. I do know I ran my 4s quad on 5v rail when I blew the power module. Maybe 8-10 flights for a total of 2 hours max...

Will spend more time reading about the larger power modules. Wish 3dr would just sell the frigging things and say this is for these esc's/motor, part b is for these esc's /motors, and part c is for these. Then tell us what to do with the pixhawk settings. I know I've read what to do on the internet, but remember giving up thinking it was to much to figure out for the non electrician.

ECalc says at max I'm pulling just under 30amp with 645 watts per motor.

Anyway, I am open to suggestions!

It is no problem at all to power the Pixhawk from the servo rail if you do not have any servos on the rail. That warning specifically talks about servos on the power rail. If you don't have any, no problem.

 

[jfro]

That's what I thought, although I wasn't 100% sure if a brushless motor wasn't considered a servo or not.... The trooper Y6 main board has 5v on the board already, so am going to use that to pins 1 and 5 on the main power in on the Pixhawk and then use a buck converter directly off the battery lead and run that to the rails for backup. Not sure if I need the diode as this would just be for backup and not sure where to get one. I just won't have amps and voltage till I can get/make the proper power module which is no big deal as I fly line of sight and can hear my voltage alarm if I get in trouble. I always land before it goes off as I keep track of my batteries (to some extent) and try not to push them anymore.

In looking to utilize my old pixhawk (with the gps surface mount receptacle pulled off the circuit board), I read that com 4/5 can be used for a 2nd gps and the pixhawk would use which ever had the most satellites. . Wondering if I can put the mag in the orig socket and the gps in the Comm 4/5 and then make some entries on the pixhawk and get it to work? Any opinion on that? I'd put this on my small test quad and fly it for a bit to test it out.

When I got the pixhawk earlier in the year, I did not like the way they did the wire connections on top. I've had a few gps masks come off (2-3 times) , but never had 1 penny in replacement parts regarding my FC or electronic parts. This one just pulled the socket right off the Pixhawk when the mask came off turning a crash...

 

[R_Lefebvre]

Nope, brushless motor is not a servo. That's a great idea to use the 5V supply from the Y6 board, and then a backup BEC. You do not need a diode, as the Pixhawk contains a 3-in-1 ideal diode controller. Basically, a modern power control system that is better than diodes. It basically has 3 FETs, and a bit of simple brains contained inside a single chip. It automatically selects power sources so they are never in parallel. It will only turn on one FET at a time to draw from that source, the other remain off. They call it an ideal diode controller, because it acts just like a diode, but without the voltage drop that diodes have.

Use pins 1 and 2 for power, and 5 and 6 for ground. Both of these pins are used in parallel, so you have redundancy of the wiring and the connector pins.

There's some info here about using 6S:

http://copter.ardupilot.com/wiki/common-using-a-pixhawk-with-6s-batteries/

Yes, you should be able to just plug a GPS into the Comm 4/5, and it should just work. I don't think you even need to change any settings. The only issue, I believe, is that you won't get a read-out of the satellite HDOP and #sats, as the code needs a bit of work here. It will receive the GPS position, and status of lock/no-lock from the second GPS. But it report all the health status from the second. Give it a shot...

Another option, would be to use a UAV-CAN GPS plugged into the CAN bus port. This is a bit bleeding edge, I haven't used it myself yet. But in the future, we'll be moving all interfaces over to CANbus as it's superior to I2C.

 

[jfro]

Rob, I checked in to the UAV-CAN GPS on Can Bus port. Probably above my capabilities right now. Will watch it for the future. Appreciate your help and suggestions.

Worked on the Y6 abit today. Little setback (timewise) in trying to get my ESC's into the 30mm arms. I wasted a bit of time trying to lengthen the power cables and then re-shrink wrap the ESC. My wrap is thicker so that didn't work. Ended up having to push ESC's into arm using a wood dowel. Not sure how I'm going to be able to monitor or measure heat, but others claim it works.

Also, am rethinking using the Pixhawk on this. There is not alot of room inside the frame. I can probably make it fit, but am also considering putting my SuperX on it as it's on a quad and I paid for 8 engines.. It fits very nicely inbetween all the connections in the middle of the frame. Pixhawk would have to go up a layer and I'd have to fiddle around a bit more. Right now I'm going to wait till all motors and arms are mounted and then make decision.

 

[jfro]

Sorry I haven't reported back. Ended up buying new ESC's (thin ones) as mine were a tight fit and I wasn't comfortable.

They came in while I was busy and then 2 days later the winter crude (nasty cold) got me. Still laying low, but hopefully will have some energy soon to get back on this.

One issue I recently saw reading the forum that has me a little worried (I wanted this to be my main over the water MR) was that many have reported that redundancy seems to work pretty good when an upper motor dies, but not so much on the lower motors. ? experience there anyone?

 

[glider]

What ESC's did you get? I went through 3 different SimonK ESC's until finally got HobbyWing 40A OPTO. They work great and flight time increased, run cool. They fit in the tubes, don't about the Trooper arms though.
I have Sky Hero Spy 750 and KDE 2814XF-515 motors, Pixhawk FC.

What I (and others) have found with the Y6 is the top motors spin slower than the bottoms. With the HW ESC, I set the top motors to high timing and it grouped the pwm's closer than previous ESC's, but have yet to try the default intermediate timing on all 6. HW says the high setting reduces efficiency but makes the motors spin faster. Over the next week weather permitting I'll try intermediate to see if it changes.

Another option is putting smaller props on top. The Y6B has 10x4.7 SF props, but don't seem to run well with mixed sizes of props. The motors get hot unless everything is balanced including CG.

I ended up using gram scales for the Y6B to get the best CG possible. $8 apiece on Ebay and simple as pie to get perfect weight distribution. The pic is with APC MR props. It now has 14x5.5 CF, but am getting 15's for the bottom.

IMO, the Spy/Trooper design does not lend to highly efficient prop thrust due to the large arms and motor housings (which also inhibit convective heat flow). But it is what it is so will try to make it the best flying possible. That said, the frame is very strong and vibration levels are within +/- 1 generally.

 

[jfro]

I've had a winter cold so haven't gotten much done. However, I did get a quick 4 minute maiden in. Brought it into adjust the gains, went back out to fly and on startup an ESC in the arm caught on fire. Was using SimonK flashed Maytech skinny 40amps. Sent pics to dealer and he said they work fine, but have had some burn up on first start. Bad QC. Anyway, I've lost faith in those and going to try some thing else in the arms. In the meantime, I'm reworking the top plate and going to put 6 old Plush 40amps I have that work fine with the KDE 3520's on a quad I have. I had four left over so just bought 2 more while the other's get sorted out. They won't fit in arms, so will be a bit messy up top, but that's how it goes sometimes.

I was a little bit disappointed looking at the vibration numbers form my xAircraft black box. They were acceptable, under 1.0, but much highter than the same motors on my x8. I attribute it to the flimsier main plates. I used thicker, more solid plates on my X8 and it's very rigid. This frame is light, but has a little flex in it. Will wait till I get a couple gimbals and look at the video before I make any judgment plus maybe getting the gains tuned better will help.

It will probably be a few more days before I get out testing again, although the weather right now is very mild for winter and winds are under 15mph for the next 2 days.

 

[jfro]

I started putting the Trooper y6 back together and as I'm putting the motors on the 2nd arm with longer 14awg wire to get to the ESC's which are now in the middle, I notice one of the motor mounts has a crack in it. I'm a bit confused as I'm screwing it down and I see the crack. I've read they are pretty flimsy so I got longer motor screws and put washers on the back side to help. Guess that wasn't enough.

I'll sit on this over night, but my gut feeling is this frame is too flimsy for my liking. I like my frames strong even if it costs a little extra weight. This frame has been in the air less than 7 minutes and it landed softly on the one flight. Motors and props balanced. It's beyond my imagination that I'd crack a motor mounts so soon.

I'll report back later, but if I had to decide right now, I'd sell the frame and mark it up to lessons learned. Then I"ll have to decide whether to build another y6 or maybe go to a flat 6. There are some new frames out with folding arms that look pretty interesting or I may just build my own and not worry about it folding. Too much to think about, but that's where this build is for right now. Just disappointed in the the poor mounts as reported by many others.....

 

[glider]

I feel the same as you, and don't know about the Trooper, but the Sky Hero Spy motor mounts are not supposed to be tightened fully around the arm; there should be a gap there or else it puts too much stress on the screw bosses and they'll crack. At least you didn't lay down $500+ for a Spy!

You could always go for these:
http://www.kdsmodelsusa.com/category-s/1892.htm

If I decide to keep flying this thing, the motor mounts are getting swapped out. One major reason is my motors are 35mm and the motor mount diameter is 37, effectively blocking convective heat flow from the motors. I've only flown in cold weather, but I'll wager they'll get hot during warm temps.

Also, putting ESC's in the arms is a horrible design IMO. ESC's, like any electronic component, lose efficiency or worse without proper cooling.

Another problem with these designs is the slop in the screws that hold the booms to the frame allow the motors to become out of alignment to each other, causing yaw issues. The arms can be rotated ever so slightly, but enough to screw things up. I adjusted everything in and do not fold the arms anymore. The 750 isn't that large to matter anyway to me.

 

[jfro]

I looked at the kdsmodels you linked to . What bother me about those is cf tubes don't like alot of clamping pressure on the ends. The collapse. While there seems to be a bit of length where it goes over the end of the tube, 2 screws holding it down, make me a little nervous.

I'm about 1/2 way through moving everything over to a Tarot x6. Liking it so far. Stronger frame, appearance wise anyway, as I'm putting it together. Proof will be when it flies.

 

[glider]

I've seen a few guys with the Kylin but no word on if they're having problems with them. Depending on the exact size of the tube vs the machining on the mount, I see your point.

I'm seriously thinking about going to a different frame, maybe even X8 (have enough motors), or build a standalone X4. I don't want a large heavy frame, or heavy frame at all, sticking with the 515 motors for now and they are more efficient on 4s than 6s, and I have lots of 4s batteries. No plans for big heavy cameras, not really into that, maybe a 2d gimbal and again....light....setup is always important to me; flight time rules the day.

There are so many Tarot models I don't know where to start. Some say the plastic parts break, others say they're great. Which model did you get? What is frame weight?

The Behold 650 Valkyrie looks like a strong frame (all aluminum inside) and is light, but I've heard there aren't many accessories available such as battery trays etc., whereas there's an attachment for just about everything for a Tarot.

I was looking at a Steadidrone hexa http://www.steadidrone.com/airframes-kits/steadidrone-siks-airframe but looks a bit pricey for what it is. OTOH, their clamps use o-rings which is good, and use high quality material. The Mavrik is $995......not going there.