Remote controlled flying things-Quads, Hex, Octo or anything

[CBRK]

I tried to do the ESC calibration and it didn't work for some reason through the pixhawk, I was so keen to go for a fly I decided to fly as it......  I'll try the individual ESC calibration tonight.

I reviewed my old logs and I was surprised to see that I wasn't hovering at 18A at all but 21A, so I'm only just off what i had before.  So only need a small diet :-).  At present I dont go over 28A, in the logs for the old tricopter I had regular spikes to 35A, so I know I was getting full lift when I needed it.  ESC calibration definitely appears to be the issue, so I'm feeling a bit happier about it.

Has anyone else played with 3 axis extension board for an 8 bit alexmos controller?  Just that mine seems to now be working now, I've read that they are inconsistent in quality.  If you do have one how did you find it, did you have to do anything to get it working?  As soon as I plug it in I'm unable to get a reliable connection to the main board, about one in every 10 attempts works.  As soon as I then connect the battery power (3s) it then freezes the output from the main board.  So I'm back to a 2 axis gimbal at present.  I think I'll put an order in for the another 2 axis gimbal (8 bit) and a bigger yaw motor, the one I have (2208 80KV) struggled with the weight of the action cam.  I'll see what GLB says when I report it as faulty - to only get a few days of use is a bit unfair.

I switched to the mini quad after 2 batts worth of flying on the tri.   Hmmm, lesson learnt today.  You have to commit, do not back off at all.  During my first flip of the day I had a thought part way that I had acro trainer turned on so I tried to abort it.  Well that results in a powered fall from 25m up into the ground at speed, I'm yet to review the mobius or FPV footage but I think it was safe to say it was above 50km/h when it hit the ground.  I lost a prop spinner, I challenge people to try to find a small green spinner on a cricket oval, I gave up after a few minutes (it could have been flung 10's of metre's).  I did leave a small dent in the ground, I was able to fix it up before leaving.  Only damage to mini quad - lost a prop spinner, 2 broken props.  I'm still to do a flight check after the crash but so far looking like I came of lightly, god knows this mini has hit trees and it's just shrugged it off other than killing props.  I like the mini quad for that reason.

Chris

[Marschy]

Howdy Chris,

Really looking forward to getting my mini quad in the air.

I purchased the replacement mini APM from Aliexpress/91Hobby about 4 days before Chinese New Year, on the same day I purchased switches, ciggy sockets and usb chargers for my brothers van. The ciggy sockets, usb chargers and switches were sent in 3 different consignments, the last of which arrived today. I am still waiting for the bloody APM boards to arrive and getting mighty impatient in the meantime. I checked the consignment tonight, and it has only just left China today, so still possible 2 weeks before delivery. Arrrrrgh.

I've read that if you use plumbers tape this helps stop the spinner nut from unscrewing due to inertia when the prop stops spinning. The prop still loosens, but at least the nut doesn't do a runner.

Cheers, Marschy

[CBRK]

Howdy Chris,

Really looking forward to getting my mini quad in the air.

I purchased the replacement mini APM from Aliexpress/91Hobby about 4 days before Chinese New Year, on the same day I purchased switches, ciggy sockets and usb chargers for my brothers van. The ciggy sockets, usb chargers and switches were sent in 3 different consignments, the last of which arrived today. I am still waiting for the bloody APM boards to arrive and getting mighty impatient in the meantime. I checked the consignment tonight, and it has only just left China today, so still possible 2 weeks before delivery. Arrrrrgh.

I've read that if you use plumbers tape this helps stop the spinner nut from unscrewing due to inertia when the prop stops spinning. The prop still loosens, but at least the nut doesn't do a runner.

Cheers, Marschy

Ouch, that is a fair wait still, hang in there.  That seems to be the big issue with some of the supply chains, they can take a week or two to just ship your goods.  Its so frustrating.

Man you will love it once you get the mini in the air.  I take her for a spin every now and then (try for once a week), this was only my 3rd attempt at doing a flip, the other two went well.  Thanks for that, teflon tape on the threads it is, I guess it will loosen which is what you want but stop them flying off in some random direction......  According to the OSD replay I hit the ground with a horizontal speed of 30km/h and had a vertical drop of 700m/m (so 11m/s) - I also didnt realise how close it was to me as it came down.  I'm surprised I didn't do any major damage (hoping as I haven't done a full check yet), this wasn't just a low speed drop it was a hard impact , I took a chunk out of the ground.

Chris

[CBRK]

I've redone the ESC calibration and it still wont go above 28A with one spike to 30A but it never goes above it - I can see in my logs I was regularly going above 30A on my old setup.  So my 4s has just arrive at my parcel locker so I'll try the system on 4s to see if it's any better.

Failing that I'm thinking so that I don't loose my 3s batts i'll jump to 6s.  That way I can use those batts in parallel.  I'm thinking of finding some ESC's and motors that are 4s to 6s capable so that I can use the 4s batts or the 6s (2 x 3s in series).

I'm thinking of resurrecting my plywood frame with the APM as it just works......

Chris

[Marschy]

Here are some 6S motors Chris.

Emax MT3515 640kv 2870 grams thrust max, rated for 13-15 inch props

Emax MT3110 480kv 1620 grams thrust max, rated for 11-14 inch props

Emax MT4008 380kv 1750 grams thrust max, rated for 12-15 inch props

My 3506's are only 3-5S, but these motors are smooooooth.

If you do choose to go with Emax, get them from the Bingo Model store on Aliexpress. The emaxmodel web site charge like wounded bulls for China Post shipping, even though they are the same mob.

http://www.aliexpress.com/store/group/Brushless-motor-for-Multirotors/216344_253579101.html

And some 6S ESC's with BLHeli at good prices as well

http://www.aliexpress.com/store/product/BLHeli-Series-30A-OPTO-ESC/216344_32268874871.html

http://www.aliexpress.com/store/product/BLHeli-Series-40A-UBEC/216344_32268665461.html

[CBRK]

Here are some 6S motors Chris.

Emax MT3515 640kv 2870 grams thrust max, rated for 13-15 inch props

Emax MT3110 480kv 1620 grams thrust max, rated for 11-14 inch props

Emax MT4008 380kv 1750 grams thrust max, rated for 12-15 inch props

My 3506's are only 3-5S, but these motors are smooooooth.

If you do choose to go with Emax, get them from the Bingo Model store on Aliexpress. The emaxmodel web site charge like wounded bulls for China Post shipping, even though they are the same mob.

http://www.aliexpress.com/store/group/Brushless-motor-for-Multirotors/216344_253579101.html

And some 6S ESC's with BLHeli at good prices as well

http://www.aliexpress.com/store/product/BLHeli-Series-30A-OPTO-ESC/216344_32268874871.html

http://www.aliexpress.com/store/product/BLHeli-Series-40A-UBEC/216344_32268665461.html

Thanks Marschy,

I've been eyeing off the top motor and that 30A BLHeli ESC, the last few days.  I'll run some thrust tests tomorrow on 4s and that will decide if I invest in the 6s motors.  If 4s works then I guess I'll be investing in a bunch of 4s batteries, either way is going to be expensive.  I'll have to buy another 3 or 4 4s batteries or if I go the 6s then I'll need 4 motors and esc's (I always get at least one spare) and of course a bunch of spare props.

Good tip about the aliexpress option.  I'll be checking them out.

I have some thinking to do some testing to do.  Testing I'll try for tomorrow:

3s 11x4.7 - do a tethered test like I did today to verify my results
4s 10x4.5 - bench test to get thrust and then a tethered test

Those above tests will be without the gimbal mount initially, I may put it back on to see what the impact is.  Camera plus gimbal has worked out to be 320g, so it's not light.

Once I've done that I'll make my decision of where to go from here.

Marschy, are you running your motors as 4s or 5s?

Chris

[Marschy]

Ridiculous isn't it. 2.8 kg thrust, that'd be enough to put a smile on your dial. And just so you know in case you haven't signed up on emaxmodels web site, the prices are the same as the prices on Aliexpress and appear to be the cheapest.

The other reason why I recommend buying from Aliexpress rather than directly from emaxmodels is the buyer protection. My one and only order from emaxmotors directly and they sent the wrong ESC. I ordered 20A they sent me 12A, but gave me a store credit for the difference. If that had of been Aliexpress, I may have got the 20A ESC's sent out for nothing and kept the 12A ESC's. Plus they charged me $24 for China Post, which is usually free on Aliexpress.

I'm running the 3506 on 4S, but only have 11 inch props at the moment, so the power to weight is under 2:1. I need to get some 12 inch props.

I have 3 4S 4000mAh Zippy flightmax batteries. I bought these quite a while ago when I started building the Alien 560, but following the Alien 560 thread on rcgroups, I should have gone for 6000mAh or bigger. With these pancake style motors people are reporting flight times of over 20 minutes using nanotech high discharge batteries. But the price is the killer, over $60 delivered for one battery, ouch.

[Crisp Image]

A small letter sized parcel arrived in my letter box.
Well it was the remains of a parcel. It did not make it through the system without damage. When I inspected it the packaging was sort of inside the badly torn envelope but the product was missing.
So now I cant Fix my broken GPS antenna.
Thanks Chris for sending it but it did not make it.
Crispy

[CBRK]

A small letter sized parcel arrived in my letter box.
Well it was the remains of a parcel. It did not make it through the system without damage. When I inspected it the packaging was sort of inside the badly torn envelope but the product was missing.
So now I cant Fix my broken GPS antenna.
Thanks Chris for sending it but it did not make it.
Crispy

Hi Crispy,

Argh, that bites.  I measured the package to make sure it was just inside the letter requirements.  I hate it when that happens.  I should have wrapped sticky tape around it to reinforce it.  I've noticed that some of the places I buy from do that.  I've got 8 others and unlikely to use them so we'll try again with a bigger envelope and with sticky tape to reinforce it.  I'll try to get that out tomorrow.

Chris

[CBRK]

Ridiculous isn't it. 2.8 kg thrust, that'd be enough to put a smile on your dial. And just so you know in case you haven't signed up on emaxmodels web site, the prices are the same as the prices on Aliexpress and appear to be the cheapest.

The other reason why I recommend buying from Aliexpress rather than directly from emaxmodels is the buyer protection. My one and only order from emaxmotors directly and they sent the wrong ESC. I ordered 20A they sent me 12A, but gave me a store credit for the difference. If that had of been Aliexpress, I may have got the 20A ESC's sent out for nothing and kept the 12A ESC's. Plus they charged me $24 for China Post, which is usually free on Aliexpress.

I'm running the 3506 on 4S, but only have 11 inch props at the moment, so the power to weight is under 2:1. I need to get some 12 inch props.

I have 3 4S 4000mAh Zippy flightmax batteries. I bought these quite a while ago when I started building the Alien 560, but following the Alien 560 thread on rcgroups, I should have gone for 6000mAh or bigger. With these pancake style motors people are reporting flight times of over 20 minutes using nanotech high discharge batteries. But the price is the killer, over $60 delivered for one battery, ouch.

I know its insane, 2.8kg per motor, that's why I've been eyeing it off, more importantly is how little current it uses at the low end.  At around 3 to 4A per motor I'd be hovering even with the additional weight of the battery, esc and motor.  I'd get 20+ mins flight time off 2 of my 3s 5000mah batts.  I will have room for much more stuff in the future, I figured I may have to adjust the max output of the throttle (after ESC calibration that is) and turn the hover point right down on the FC as it would just scream along.

I'm still stumped as to why my DT750 motor output is stopping at just under 10A (thats only 120W, the motor can do 200W, ESC's can do 18A/22A).....  I know on the test bench they go another 3 amps than that and my other set of ESC's did it.  I think it might be a blessing in disguise as it will ensure that I have a tricopter fit for the future and also good for now.

I'm definitely leaning towards the the MT3515 with some large props.  That way I can move between 4s and 6s easily.

I will wait till I've done my testing as it may just work really well of the 4s batt or I might be ok on 11x4.7 for the 3s, but I suspect the 3s route wont go too far as if it even gives me another 20% would only really make it good without the gimbal.  I ruled out turning the tri into a y6 with DT750's as I'd only need 1 extra to make it happen but then I'd be 22A (3.5A per motor) just to hover as I'd have an extra 300g of weight, I'd have to change my landing gear, etc.....

Chris

[Marschy]

2.8
2.8
2.8

AU $139.10. That's less than 1 months multicopter allowance 

or for  AU $153.28 you could have 'em in 5-15 days 

2.8
2.8
2.8

[Marschy]

http://www.aliexpress.com/store/product/Simon-Series-40A/216344_2042264570.html

And then there's next month.

http://www.aliexpress.com/store/product/Simon-Series-40A/216344_2042264570.html

I'm not trying to get you in trouble with the missus, honest 

[Crisp Image]

Hi Crispy,

Argh, that bites.  I measured the package to make sure it was just inside the letter requirements.  I hate it when that happens.  I should have wrapped sticky tape around it to reinforce it.  I've noticed that some of the places I buy from do that.  I've got 8 others and unlikely to use them so we'll try again with a bigger envelope and with sticky tape to reinforce it.  I'll try to get that out tomorrow.

Chris

No problems Chris. Somethinh to look forward to.
Regards Crispy

[CBRK]

I'm not trying to get you in trouble with the missus, honest 

Sure, sure.....

Okay the results are in and I've made a decision.....

Test Bench (4s DT750/18A ESC/10x4.5 props):
23.5A - 1.7kg (it wasnt maxed out - maybe another 5-10% available, had to be careful as ESC is only burst rated to 22A so stopped)
8A - 800g

ESC & motor wasn't hotter than it gets on a 3s run.

Tethered Tests (test was with gimbal as I figured I'm more likely to fly the tri if I'm videoing something):
4s 3000mah using 10x4.5 props - 18A to 20A hover - flight time was approx 10 mins.  - What was good is if I gave it full throttle it went up to 45A so 15A per motor (under ESC's safe level) and hell did it have some lift.  Lift off point was at 50% throttle - hover just under that.
3s 5000mah using 11x4.7 props - 24A to hover - Flight time was approx 11 mins.  - I did notice that I had to increase throttle when it dropped from 11.5v under load to 10.7v under load, which I didn't have to on the 4s.  Lift off point was at approx 65% with fresh battery.  Hover increased to 70% as battery voltage dropped.

Solution:
1. Order some 3 x 4s 4000-6000mah batts (have to have a look at price, capacity, max current) also order some 13, 14 and 15 inch props.
2. Fly on 3s 11x4.7 for the short term
3. Build a 12V regulator (for FPV transmitter and 8 bit Gimbal mount - can take 4s but not 6s)
4. Order some 4x MT3515 & 4x 40A or 30A Opto ESC's (long delivery to save money)

Once the 4s batteries arrive I'll switch over to them (need to build the 12V reg by then).  Once the MT's arrive I'll switch over to them and fly on either 4s or 6s depending on payload requirements.  I may need to extend the booms if I fly with 15 inch props.....  I've measured I'm good with a 14 inch prop.  Radio mast is just a touch too close for 15inch.

Oh I'll also be ordering a 32 bit alex mos gimbal as I'm over the extension board that wont work properly......  I need a yaw that works.

Hmmm, just thinking.... I have enough spare parts then to build a mid sized quad left over from my tri then (maybe a 330 or 450?).....  I've got 5 DT750's (3 others I might be able to resurrect), 6 18A ESC, plenty of 10x4.5 props, spare APM, a 2 axis 8bit gimbal controller, I'm more likely to fly the tri on 4s (even with the MT's).  Hmmm food for thought....

Chris

[Marschy]

It wasn't my fault, you were already there, you just needed a nudge. 

[Marschy]

You're going to need some more carbon fibre booms now for those big @rse 15 inch props you're gunna need for those motors LOL

Seriously though, I think you will be very pleased with those motors. The quality for the price is pretty bloody good.

[CBRK]

It wasn't my fault, you were already there, you just needed a nudge. 

Thanks mate....
LOL, I guess your right.

You're going to need some more carbon fibre booms now for those big @rse 15 inch props you're gunna need for those motors LOL

Seriously though, I think you will be very pleased with those motors. The quality for the price is pretty bloody good.

True I was looking at that, I think I'll start with the 12x5.5 props, so I wont have to move anything.  I only ordered 12 and 14inch props today, will look at the 15's soon.

On the 4s battery front I ordered 2 x 5800 and 1 x 4000.  Plus the 3000 I already have should be plenty to get started with. 

All items ordered.  Now I'm not going to buy anything else for a while.......  I think I'll need to go back to work before the MT's arrives, grrrrr.....  The MT's and ESC's should arrive in a months time and most of the other stuff will be here next week.

I think I'll be grinning from ear to ear once it's all working!!

Chris

[Marschy]

Now if you tricopter guys buy this, just tell the missus that these opportunities only pop up occasionally and you have to grab them when you can.

Turnigy Talon half price sale

[CBRK]

Now if you tricopter guys buy this, just tell the missus that these opportunities only pop up occasionally and you have to grab them when you can.

Turnigy Talon half price sale

Not sure I like the arm locking mechanism on that tri frame.  One of the benefits is that if you do have a hard landing the tri's arms should fold back to absorb the impact.

HK has a big sale on at present.  I think some of the batteries I picked up somewhere around 30% off.

It's on till the 8th.

Chris

[Marschy]

For $50 bucks, it's still a good buy. I'm on credit hold with the missus at the moment. We have only 2 weeks to go before we go on a S/Pacific cruise, both of us celebrate our 50th birthdays this year. I asked if I could take my fishing rod and she just glared at me. Can't win.

[Crisp Image]

I got my replacement motors today for the damaged one from the follow me trial. It didn't take long to get them.
Put it on and had a quick flight in the back yard. I am getting quite good at controlling it and getting it in to the correct flight mode for where i want it.
If I get a chance I will have another crack at the follow me setting.
All is good for now.
Regards
Crispy



Sent using fat fingers on the iPad thingy

[CBRK]

I got my replacement motors today for the damaged one from the follow me trial. It didn't take long to get them.
Put it on and had a quick flight in the back yard. I am getting quite good at controlling it and getting it in to the correct flight mode for where i want it.
If I get a chance I will have another crack at the follow me setting.
All is good for now.
Regards
Crispy

Sent using fat fingers on the iPad thingy

Hi, make sure when you do the follow me mode that your in a wide open space.  We really need collision avoidance to be working to use it in denser locations.  Main things I found with follow me was it likes to cut corners is you do a rapid turn the other item is make sure it's set to a good alt above you, say 10+m is a good start - really depends on the terrain.

Chris

[Crisp Image]

I also redid my compass calibration but changed one thing. I took the ferris metal screw (read that as steel) from under the gps and replaced it with a non ferris screw ( read that as brass) and it improved my figures heaps so lesson learnt there.

The problem with our gps is the only update about once every 2 seconds. You can cover lots of ground in that time. Also does not make it so accurate to within 2m. That means it could be out by 4+m between the GPS receivers
Anyway got to give these things a go.
Regards
Crispy


Sent using fat fingers on the iPad thingy

[CBRK]

I also redid my compass calibration but changed one thing. I took the ferris metal screw (read that as steel) from under the gps and replaced it with a non ferris screw ( read that as brass) and it improved my figures heaps so lesson learnt there.

The problem with our gps is the only update about once every 2 seconds. You can cover lots of ground in that time. Also does not make it so accurate to within 2m. That means it could be out by 4+m between the GPS receivers
Anyway got to give these things a go.
Regards
Crispy


Sent using fat fingers on the iPad thingy

Where are you getting the once every two seconds from?  Reading the Datasheet for the GPS they output much more quickly than that.  I can assure you that they should update many times a second, the update on the OSD might be once every second or two but the position data from the GPS should be output at a much higher rate.

I can assure you I've watched the Mavlink data on this and it detects small changes very rapidly. 

Regards,

Chris

[CBRK]

Argh..... Seems like I could have waited to put in my order for all those motors, esc, etc.....  It will be a beast when I'm done :-)

I just took the tri out for a spin with the gimbal (plus camera) with the 11x4.7 props on 3s and it was pretty good I have to say.  I wouldn't do aerobatics with it like the mini but I felt it had plenty of power to arrest falls, i was able to run the battery fully without loss of alt towards the end.  Sigh......

Nothing appeared to be hotter than it was before, i was expecting the motors to be a lot warmer however I was using around 20A to maintain a hover so overall power going in wasnt a lot more was less.  Whats interesting is the few times I cranked it up I was getting into the mid 30's so I have the lift when I needed it.  Even got good flight time off 15 mins of a 5000mah battery too.  Hover throttle was still around 60% so it was a little under powered.

Whats cool is I clocked up 3km's of distance over the 27 mins I spend in the air (1.7 batts).  Mainly did a race track around a local oval, had to use the monitor a few times as it was hard to tell orientation at a distance.  It was windy as all heck so I didn't push my top speed but I was regularly hitting 50km/h downwind and 30km/h upwind - took a constant 20 degree down angle to hold position in the wind.  I reckon in still air it would have been even better - ie less amp's being drawn and therefore longer flight times.

Lesson learnt, my tether test is inaccurate it appears.

Chris