• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

EconoCopter Project

colorex

Rotor Riot!
Mentor
#1
:: EconoCopter Project ::

*PROJECT ON HOLD*

After watching a bunch of tricopter videos by David, I got the disease as well.
I had never looked that greedily at tricopters because most are a bit more expensive than the usual plane... So I started a thread asking about multicopter motors. I posted a question about the Blue Wonder motor, an economic, lightweight and effective motor.

Burg and Anas were kind to answer a lot of my questions.

Colorex, that HXT 25gr 1300kv is a good motor.
Best performance with a 8x4 props on a 3cell and 9x6 on a 2cell.
That makes it suitable for lets say 500mm quad / tri frames (hobbyking V1 in light spec).
So I got inspired and I thought, OK, now I'll try to make a project: Build a tricopter for us economically limited people (also for cheapskates).

Considering good and bad points about building a tricopter, I encountered the following:

+ Flying a tricopter is something new to learn since it's not like flying a plane.
+ A tricopter can be flown in limited spaces (with practice).
+ A tricopter can be easily transported to almost everywhere.
+ A tricopter can carry an FPV system, and can be used for AP.
+ Aerial Photography from a tricopter could earn me a few bucks.
- A tricopter uses thrice the power of a plane, so
- Batteries last one third of what they would last on a plane.
- A tricopter takes more damage from a crash than a foam plane.
- A tricopter is supposedly hard to build.

So, all in all, I think a tricopter would be a good idea.

----------------------------------------------
Basic tricopter building blocks:


So that is:

- 3 Blue Wonder motors
- 3 HXT900, one for tail servo, two spare
- A HK v2 Control board
- 3 9g 10amp Plush ESC's
- 6 8x4 DD props and 6 8x4 RD props (not sure which one to use)
- A programming device for flashing the control board
- A Turnigy programming card
- 2-4 Turnigy 2200mAh 20-30C LiPo's
- Maybe a helicopter blade grip
- Voltage meter
- Maybe a low voltage buzzer
- A bunch of collet type prop adapters

Making some calculations:

The motors are said to have 400gr thrust at full throttle.

400gr x 3 = 1200gr

The weight of the complete tricopter (with 2200 3s battery) might come around 500 - 600gr, so I would be hovering at about half throttle (Burg said this was good).

(Considering that I'm getting a Bixler, I like the fact that the Bixler too can use 2200 mAh 20C batteries, so I can get good use of my batteries.)

----------------------------------------------​

So. What do you have to say? I'm all ears to your suggestions.
 
Last edited:

ananas1301

Crazy flyer/crasher :D
#7
Hey colorex! Nice thread.

Question: What size are about to go for? 500-600g is a 30-40 cm Tricopter, or not? From Davids weights he gets up to 1kg or is that just because he uses an FPV system on them as well?
As you may know, I am currently building one and the hardest thing to do really is the Yaw mount! Everything else is pretty straight forward and just takes time. There will also be a lot of soldering, that has to be done.
Another point is that you will need a lot of props!
 

Burg

Never catch a multirotor
#8
Good thread Colorex,

I advise using a servo with metal gears on the yaw-system.
There will be quite some force on the gears.
Friend of mine is using this cheap servo and it works.
http://www.hobbyking.com/hobbyking/...9MG_Metal_Gear_Servo_2_5kg_12_5g_0_14sec.html
Hitec's MG are better but more expensive.

Anas is right, the only 'difficult' thing is the yaw system.
If you want a different system then David's; check this, including shopping list:
http://flitetest.com/forum/showthread.php?978-Another-tricopter-yaw-mechanism

You want easy soldering ? Get one of these:
http://www.goodluckbuy.com/multicopter-multi-tri-copter-power-battery-to-8-esc-connection-board.html
Or these for simply adding LED's
http://www.goodluckbuy.com/multicop...ry-to-8-esc-8-led-strip-connection-board.html

Good luck ! I subbed ..
 
#10
If you choose to use CCV/CV propellers on a Tricopter you put them in front and this results in less tilt to one side of the Tricopter that tends to lean a bit if you use all similar props.

It also means the tilt rotor has to tilt less to keep Tricopter in the direction you want to.

I say go with stuff that have been tested - the main reason Dadde's Tricopter is so popular is that it works well.
When I built my 1st Tricopter I pick my own stuff and it also worked great with bigger payloads.
 

colorex

Rotor Riot!
Mentor
#11
Hey colorex! Nice thread.

Question: What size are about to go for? 500-600g is a 30-40 cm Tricopter, or not? From Davids weights he gets up to 1kg or is that just because he uses an FPV system on them as well?
As you may know, I am currently building one and the hardest thing to do really is the Yaw mount! Everything else is pretty straight forward and just takes time. There will also be a lot of soldering, that has to be done.
Another point is that you will need a lot of props!
I don't think the size changes the amount of power needed (not much), just increases the distance between the motors making it more stable.

I think I'll go with 40-50cm radius tricopter.

About the weight, I'll have around 1200gr thrust at full throttle, so I can pull 1 kg slowly.

Good thread Colorex,

I advise using a servo with metal gears on the yaw-system.
There will be quite some force on the gears.
Friend of mine is using this cheap servo and it works.
http://www.hobbyking.com/hobbyking/...9MG_Metal_Gear_Servo_2_5kg_12_5g_0_14sec.html
Hitec's MG are better but more expensive.

Anas is right, the only 'difficult' thing is the yaw system.
If you want a different system then David's; check this, including shopping list:
http://flitetest.com/forum/showthread.php?978-Another-tricopter-yaw-mechanism

You want easy soldering ? Get one of these:
http://www.goodluckbuy.com/multicopter-multi-tri-copter-power-battery-to-8-esc-connection-board.html
Or these for simply adding LED's
http://www.goodluckbuy.com/multicop...ry-to-8-esc-8-led-strip-connection-board.html

Good luck ! I subbed ..
Thanks! I didn't know I needed a MG servo...
I was planning on the helicopter blade thingie. I think it's the strongest. (but expensive!)

Nothing is too difficult. Some things are more difficult than others.

I don't think I'll need soldering aids, they're just dead weight.

Dont tricopters use any counterrotating prop at all?
Nope, They use the yaw mechanism to counteract torque.
 

colorex

Rotor Riot!
Mentor
#12
I say go with stuff that have been tested - the main reason Dadde's Tricopter is so popular is that it works well.
When I built my 1st Tricopter I pick my own stuff and it also worked great with bigger payloads.
Ummm, I'm not really sure about this, but it's the EconoCopter project anyways... But David's tricopter is a bit more expensive... I'll check it out though.
 

ananas1301

Crazy flyer/crasher :D
#13
His Tricopter just opened up the doors for everyone not necessarily having to be a soldering and DIY specialist to build one themselfes! He has introduced it to the open minded people willing to learn this rather new kind of stuff.

Have you already got an idea of how you´re going to do your yaw mechanism? The idea with the blade grip works out nicely, but the at the moment I´d need to do an extra order just for the blade grip, which I think isn´t worth it, so I am currently trying to make up my own one from scratch with stuff I got at home somewhere. Pretty tough!

Good luck with yours anyway. Are you actually planning on building a Tri or just looking for how to set it up etc.? I did that sometimes earlier. It is like loosing interest into it after a while
 

colorex

Rotor Riot!
Mentor
#14
Are you actually planning on building a Tri or just looking for how to set it up etc.?
I'm thinking that it would be nice to have a tricopter, so that I can fly in lots of places I can't fly planes... And later I can get a bigger one to put a camera on it and go Air Photo and maybe FPV...

I also had in mind to scratchbuild a plane, but I think that if I work like a mule I can save up enough for both... Otherwise I'll just go with the tricopter since it's different from a plane...

FPV and Aerial Video looks like a promising field for the local TV news channel, they'd probably like to have aerial footage in their news reports without paying for a helicopter... They might still shell out a deal of money for aerial video!

Right now, I could order parts for the tri (without batteries) but I'll wait till my plane arrives and till Chinese new year is gone.
 

pgerts

Old age member
Mentor
#15
About the weight, I'll have around 1200gr thrust at full throttle, so I can pull 1 kg slowly.
You have to remember that the thrust measured is with a new battery.
Electric is not like glow - full power all the time.
The power will go down relatively fast to a lower level and then more slowly be less.
Specially if you are getting cheaper batteries - the power does not degrade as fast with hi C batteries.
Say you start with about 12,5 volts but relatively soon the voltage is down to nominal 11.1 and you can probably fly down to 9,5 volts.
If i remember the Ohms law then P=U2/R and the resistance is a constant (approximately).
Then you will find that the power goes down to about 60% of the top value during flight.
 

colorex

Rotor Riot!
Mentor
#16
Oh, but anyways, It will still have enough thrust for it's own weight. It's just a practice copter, not a full heavyweight lifter...
 

colorex

Rotor Riot!
Mentor
#17
OK, guys:

Here you go, tell me quick if I'm making a mistake or if I need something else!

Weight

Quantity

Stock

Product description

Price

[TD="align: center"]

[/TD]

 

[TD="align: center"]OK[/TD]

HXM2730-1300 - hexTronik 24gram Brushless Outrunner 1300

$24.99

[TD="align: center"]135[/TD]

 

[TD="align: center"]OK[/TD]

TR_P12A-E - TURNIGY Plush 12amp (2A BEC) BESC

$24.00

[TD="align: center"]105[/TD]

 

[TD="align: center"]OK[/TD]

HXT900 - HXT900 9g / 1.6kg / .12sec Micro Servo

$5.38

[TD="align: center"]36[/TD]

 

[TD="align: center"]OK[/TD]

GWS-RD-8043 - GWS EP Propeller (RD-8043 203x109mm) (6p..

$3.05

[TD="align: center"]55[/TD]

 

[TD="align: center"]OK[/TD]

T-Neckstrap - TURNIGY Transmitter Strap

$0.73

[TD="align: center"]69[/TD]

 

[TD="align: center"]OK[/TD]

TR_PC - TURNIGY BESC Programming Card

$4.19

[TD="align: center"]50[/TD]

 

[TD="align: center"]OK[/TD]

9171000003 - USBasp AVR Programming Device for ATMEL

$4.18

[TD="align: center"]35[/TD]

[TD="colspan: 4, align: right"]

[/TD]
[TD="align: center"]485g

[/TD]


Plus $10.00 Shipping