Quadcopter Build

[izeman]

oh man. putting YAW and ROLL on the correct sides makes flying MUCH easier i had THROTTLE + ROLL and YAW + PITCH together!
that must have been the cause why i couldn't adjust settings with my sticks. sure. if they are mixed up it can't work.
i should have started to think because i had to change the default

#define ALLOW_ARM_DISARM_VIA_TX_YAW

to

#define ALLOW_ARM_DISARM_VIA_TX_ROLL

to make arming work. all those beginners problems you can run into!!!
now i can calibrate ACC with my sticks as well (LOWER LEFT + DOWN)
still flying needs a lot of training. throttle eg is VERY aggressive. i set MID=0.20 and EXPO=0.00 but i'd like to smooth the throttle a bit.

 

[izeman]

okok. setting THROTTLE EXPO to ZERO is a stupid idea. that makes THROTTLE totally linear. if you RAISE EXPO it gets smoother. so big stick movements in the lower values make the revs turn up only a little.
i guess this thread will be a kind of compendium of trial&error for me. i hope that's ok for everybody. i guess i'm not the only one making those mistakes.

 

[nechaus]

yeah man its good!

 

[nechaus]

something that is simple but not yet figured it out..

The buzzer, I cant seem to be able to reassign the pins correctly in the arduino code for the mwp board..
The buzzer is used to alert you when you change flight modes and if you have a power cable should work as a low voltage buzzer
or you can use a combination of leds and buzzer...

I mucked around the other day but not yet figured it out, ill check it out again when i end up building the hex.

 

[izeman]

something that is simple but not yet figured it out..

The buzzer, I cant seem to be able to reassign the pins correctly in the arduino code for the mwp board..
The buzzer is used to alert you when you change flight modes and if you have a power cable should work as a low voltage buzzer
or you can use a combination of leds and buzzer...

i'd like to use the buzzer a lot more also. armig and disarming is obvious as the rotors start to turn. but as you said: get some audible feedback for actions you set (change flight mode eg) would be a nice addition.
i also think about adding leds - no only for orientation and night/dawn flying, but for the status leds. they tell you a lot: from gps status to some warnings (no level etc ..) but i can see them as they are too weak/small and hidden below the upper plate. my board is installed on the lower plate. the battery sits on the upper plate.
for battery monitoring i've got a standard led/buzzer connected to the balance plug. i will install telemetry and will get some warning directly on my remote so i can remove the model's buzzer.
i'd like to have some beeping if the copter is turned on and UNARMED. this makes it easier to be find in high grass. when i land (or more often crash) i disarm it immediately to stop the rotors that are blocked by high grass anyway.

 

[nechaus]

something that is simple but not yet figured it out..

The buzzer, I cant seem to be able to reassign the pins correctly in the arduino code for the mwp board..
The buzzer is used to alert you when you change flight modes and if you have a power cable should work as a low voltage buzzer
or you can use a combination of leds and buzzer...

i'd like to use the buzzer a lot more also. armig and disarming is obvious as the rotors start to turn. but as you said: get some audible feedback for actions you set (change flight mode eg) would be a nice addition.
i also think about adding leds - no only for orientation and night/dawn flying, but for the status leds. they tell you a lot: from gps status to some warnings (no level etc ..) but i can see them as they are too weak/small and hidden below the upper plate. my board is installed on the lower plate. the battery sits on the upper plate.
for battery monitoring i've got a standard led/buzzer connected to the balance plug. i will install telemetry and will get some warning directly on my remote so i can remove the model's buzzer.
i'd like to have some beeping if the copter is turned on and UNARMED. this makes it easier to be find in high grass. when i land (or more often crash) i disarm it immediately to stop the rotors that are blocked by high grass anyway.

yep sounds good, can you make sense of this?

/**************************************************************************************/
/******** override default pin assignments ********************/
/**************************************************************************************/

/* only enable any of this if you must change the default pin assignment, e.g. your board does not have a specific pin */
/* you may need to change PINx and PORTx plus #shift according to the desired pin! */
//#define OVERRIDE_V_BATPIN A0 // instead of A3 // Analog PIN 3

//#define OVERRIDE_PSENSORPIN A1 // instead of A2 // Analog PIN 2

//#define OVERRIDE_LEDPIN_PINMODE pinMode (A1, OUTPUT); // use A1 instead of d13
//#define OVERRIDE_LEDPIN_TOGGLE PINC |= 1<<1; // PINB |= 1<<5; //switch LEDPIN state (digital PIN 13)
//#define OVERRIDE_LEDPIN_OFF PORTC &= ~(1<<1); // PORTB &= ~(1<<5);
//#define OVERRIDE_LEDPIN_ON PORTC |= 1<<1; // was PORTB |= (1<<5);

//#define OVERRIDE_BUZZERPIN_PINMODE pinMode (A2, OUTPUT); // use A2 instead of d8
//#define OVERRIDE_BUZZERPIN_ON PORTC |= 1<<2 //PORTB |= 1;
//#define OVERRIDE_BUZZERPIN_OFF PORTC &= ~(1<<2); //PORTB &= ~1;






I want to be able to reassign buzzer pin to a spare one like one of the cam ones..

 

[izeman]

o man that thing stings like a bee. really. it hurts! had i flying at 2m height when it turned around hunting me. i disarmed immediately. still it hit me. i guess i will start to wear protective clothing. one propeller hit me where my polo shirt ended leaving a little scratch and a blue spot. same happened to my ankle. a little scratch. and the 'wounds' feel like a bee's sting. won't imagine how it hurts if it hits you with propellers on full throttle and from a big height.

 

[izeman]

pid tuning seems more complicated than i thought. i really learn how to do it, but the more i try the more unstable it becomes.
i start with roll/pitch at p=1. i and d are at zero. and then start raising p until it starts over steering. but it's not controllable that way.
what do i do wrong?

 

[nechaus]

the pids for Pitch and roll are pretty good, i use anywhere from P 2.8 to 3.5
you can increase the level P a bit.. might make it more easier to hover better with out mucking with throttle...

get it to fly stable, should be no wobbles... You should be able to roll right hard and let go of stick and it should correct itself.. no over corrections..


For Alt i use like P: 1.5 - 1.8 I: 60 D:30


You can increase the YAW P if you want it to hold yaw position better...

can you take a video of it in action?

 

[gogo]

Sorry if this is off topic, I haven't read this whole thread yet.

http://blog.ted.com/2014/09/12/sergei-lupashin-brings-aerial-photography-down-to-earth/
The link above mentions tethered copters. It occurs to me that would be a great way to photograph our rides, and maybe to see farther forward and behind for navigation assistance.

With some software it might be a good way to warn of vehicles approaching from the rear on high speed roads. Some sort of attention causing device on the bicycle could be activated. Maybe after a few cage drivers are documented negligently running into cyclists, the motoring public will understand that they should be scared to death of injuring vulnerable road users because their actions are being fully documented. You could even have multiple copters launched when a cager closes in at a high rate, with one of them getting a face view though the windshield showing them not looking where they're going. Maybe posting videos of drivers caught in the act of distracted operation would be enough to shame them and make them lose huge settlements when they cause injury and death.

 

[izeman]

sorry, but beside from being OT , this is really strange. you need rear view assistance while biking? i would install a mirror. that works 100%, is fool proof and won't possibly REALLY harm people. what would happen if two "drone assisted" riders with one or more drones swirrling above their' heads cross the same intersection? or heavy downtown traffic. crashing drones calling from the sky?
not to mention taking care of their batteries. and what happens if the batteries are empty? collect them and then? transport them home on you bike. a total no-go in my opinion.
letting them record your ride on a clearly defined course may be another thing. that at least sounds like fun

 

[izeman]

yesterday was a nice day and i made some videos with a friend flying the copter.
in the first video you can see the copter over steering.

[youtube]86cV-EWo5NY[/youtube]

at the second video we got BARO enabled. at the end you can hear my friend say "--- we've got a problem" the copter just gained height going higher and higher with no throttle input

[youtube]POZ5gvu7xRM[/youtube]

what do you think? i would like to tame it. it's VERY sensitive on throttle input.

[youtube]NUSOljv6dy4[/youtube]

the flight session ended with the copter suddenly nicking to the side going from horizontal to vertical flight hitting the ground from around 5-6m height at quite some high speed. two propellers smashed.

 

[nechaus]

okay a few things I can think of that might help you...


The baro...
You need to really drop the P in ALT to like 1.7 or around that.. and Increase I to 60-70
I had this issue of it gaining altitude.. This is how i fixed it..
Also using foam over the baro and enclosing the FC in a container with tiny vent holes..
Start with the foam and test see how it goes.. you should be able to get good result and actually trust the baro...
The container is more for when it is really windy.. or flying hi altitudes


Throttle being to sensitive.. I would try and create a throttle curve that is suited to you..
you can also try and increase the LEVEL P from 9.0 to 10. but only do this after you mucked with the throttle curve.
Increasing the LEVEL P i found it to hold its altitude easier.. again this is trial and error.. dont change to many things at once.. work on one thing at a time



The erratic behaviour

 

[nechaus]

yesterday was a nice day and i made some videos with a friend flying the copter.
in the first video you can see the copter over steering.

[youtube]86cV-EWo5NY[/youtube]

at the second video we got BARO enabled. at the end you can hear my friend say "--- we've got a problem" the copter just gained height going higher and higher with no throttle input

[youtube]POZ5gvu7xRM[/youtube]

what do you think? i would like to tame it. it's VERY sensitive on throttle input.

[youtube]NUSOljv6dy4[/youtube]

the flight session ended with the copter suddenly nicking to the side going from horizontal to vertical flight hitting the ground from around 5-6m height at quite some high speed. two propellers smashed.

Okay I have watched these videos a couple of times...
And I think this may help you with the craft being more stable, From what I can see it looks like its drifting?


What you want to do is make sure the quadcopter is on a level surface, as well as the FC level with the frame.
Calibrate the ACC..

Next step is to trim the quadcopter via the flight controller..

The way to do this is by
1: arm quadcopter in level mode
2: take off about half to a meter and take note of which way it needs to be trimmed
3: land and disarm
4: put throttle all the way up, should reach above 1900
5: use Pitch or roll to trim, Hold that stick position for 3 seconds
e.g. Quad drifs to the right, Hold roll to the left for 3 seconds and you should see the light blink on the board to confirm this.
6: Repeat this process about 3 or 4 times, each time you do it, its one click for the FC trim..
7: test and see if its better.
8: do it all again if required.

this video explains it well [youtube]Foc8lxDddHw[/youtube]

 

[Deanwvu]

Hey guys,

i am still waiting on my HK orders to arrive, but in the meantime, I have come to change my plans.


I am going back to a quad build in a "dead cat" orientation, as this will give me the best platform (that's not a huge octocopter) for FPV.

So, all my components will still work great, but I ordered this frame (it's actually a frame and a conversion kit):

 

[nechaus]

Hey guys,

i am still waiting on my HK orders to arrive, but in the meantime, I have come to change my plans.


I am going back to a quad build in a "dead cat" orientation, as this will give me the best platform (that's not a huge octocopter) for FPV.

So, all my components will still work great, but I ordered this frame (it's actually a frame and a conversion kit):

Nice !!!
I actually ordered that dead cat conversion kit without realising it did not come with the legs... you just get the top and bottom plate, they do not fit the regular f450/f550 arms..

its nice but! plenty of room for all your gear
The plates are actually quite big. I can take a photo for you if you like

 

[Deanwvu]

Any idea where to find LED strips like what is on this one??

 

[nechaus]

Any idea where to find LED strips like what is on this one??

yep, you might want to get a remote relay as well, so you can turn lights on and off via transmitter
http://hobbyking.com/hobbyking/store/__280__58__Hardware_Accessories-Night_Flying_Accs_.html

 

[nechaus]

Hey guys, I ordered my friend a mini quad 250mm kit from hobbyking, the one that's about $111 or whatever..
it arrived today.. all comes really nicely packaged.. no chance of getting stuff damaged in transit



Will build it today I think..
a photo comparing the motors to the other small motors I was originally using.. I thought they were small.

 

[izeman]

Any idea where to find LED strips like what is on this one??

http://www.ebay.de/itm/111403790084

 

[izeman]

i've got 3530 motors installed. those are known to draw 22a max. if i got 4 of them, this would equal 88a. so if i want to install an AMP-sensor (acs758) to monitor power usage and battery drainage, i would need a 100a type. correct? i'd like to use a 50a type. is this 22a number realistic? or will i never use that much power with 10x4.5 props on a 3s battery?

 

[Deanwvu]

Nechaus,

Is the 250 you bought similar to this one:

https://www.youtube.com/watch?v=9JiiZs-wdo4


I've really got the itch to buy one of these minis! Perhaps after I practice a bit on the 450 size and have some FPS gear... Looks like a TON of fun to fly (I think this guy knows how to fly too)

 

[nechaus]

Nechaus,

Is the 250 you bought similar to this one:

https://www.youtube.com/watch?v=9JiiZs-wdo4


I've really got the itch to buy one of these minis! Perhaps after I practice a bit on the 450 size and have some FPS gear... Looks like a TON of fun to fly (I think this guy knows how to fly too)

looks like a good video!
yeah he was flying good hey, I like it...
The one i got for my mate is this one
http://hobbyking.com/hobbyking/store/__52863__HobbyKing_Spec_FPV250_V2_Quad_Copter_ARF_Combo_Kit_Mini_Sized_FPV_Multi_Rotor_ARF_.html

Its his first one,

Testing it yesterday inside, Using the multiwii 328p board from hk, It was really really stable inside.. you could get it to stay in on position for atleast 15-20 seconds with no drift...


i would personally prefer bigger motors, the motors it comes with are pretty much the smallest brushless motors I have held in my hands, still has plenty of grunt and climbing ability ...

 

[izeman]

@nechaus: i know that PID values are not inter exchangeable between different copters. but still: could you please give me your pid values for your 450er copter with 3530 motors and 10" rotors which is the same as mine. i'd like to have this as a starting point.
another question: i have troubles holding height. so i have to play a lot with the throttle. and it happens often that i hit the ground quite hard, and then the copter JUMPS up again. how can i suppress this jumping? and where does it come from?

 

[izeman]

btw i made a video. quite blurry, but that's not important imho. and it's dark. on purpose. because that way you can see the esc's leds. you see me arm it, then disarm it. esc's leds go out unevenly - i guess because the rotors don't really stop at the very same time. does that matter?

[youtube]S9Wjnzh_NbQ[/youtube]