rcexplorer.se Tricpter v2.5 with MultiWii

[EOSBandi]

Hi,
It finally snapped together. Latest dev code with path for BMA020 8G range. Video is unedited (only some grading was done). It was filmed in Stable+head free mode.

It is AWESOME!!!

http://www.youtube.com/watch?v=4km0_CbF6lc
Regards,
EOSBandi

[kataventos]

Hi, nice, what I like most is the fast smile at the end!

Cheers,
Henrique

[PatrikE]

Latest dev code with path for BMA020 8G range.

How can i change the range?

Code: Select all

#if defined(BMA020)
void ACC_init(){
  i2c_writeReg(0x70,0x15,0x80);
  uint8_t control = i2c_readReg(0x70, 0x14);
  control = control & 0xE0;
  control = control | (0x00 << 3); //Range 2G 00
  control = control | 0x00;        //Bandwidth 25 Hz 000
  i2c_writeReg(0x70,0x14,control); 
  acc_1G = 255;
}

[Quadraf]

Great movie .Wich mag do you use and how is it connected. Can you tell us more about your setup, some pictures would be nice

[KeesvR]

How can i change the range?

Here you can find it.
viewtopic.php?f=8&t=849&start=70

[PatrikE]

Great tnx..

[EOSBandi]

Here are some pictures...

Foldable for easy transport

Buzzer moved to the rear arm

Sensor blobs: ITG3205 from WMP, Self made HMC5883 on top of it, and a shielded BMA150. (BMP085 is underneath the board)

Self made FC with AtMega2560

Solid state relay array for controlling lights

Power wires are far away from FC and sensors, all glass fiber board has copper foil

GPS is elevated and away from electronics

[EOSBandi]

Hi !
Alt and vel pids are :
ALT P 2,5 I 0,025 D 0
VEL P 4,1 I 0,020 D 40
AccZ is trusted, and accelerometer range were set to 8G. (BMA150 is the same as BMA020)
AUW is 1390gramms with a 3S1P 5Ah lipo. flying time a little bit above 15 min.
With gopro I change the battery to 4Ah to maintain weight, and flight time drops to 12min.

The electorincs and the casing are standing on rubber standoffs (something like this : http://www.nghobbies.com/cart/index.php ... a7cbf073ee) But search for it in your local hardware store, since hobby shops are selling them overpriced).
Other that the standoffs just a normal stiff hobbyking double sided sticky foam.

[Quadraf]

Thank you for the pictures Very nice to see your mag is performing so well sitting on the electronics . Maybe you are the first person who can succesfully show us a GPS home performance with multiwii...
I miss your roll/pitch pids...

[EOSBandi]

OK then, here is the full set of PID's

[jevermeister]

Hi,
I tried your Baro PID and it is very close to optimum.
It is only oscillation around 1m but has a tendency to loose height, I will work on that when it is getting warmer.

Thank you very much for those PIDs

I twisted my wires LIP->ESC and the mag is behaving a little bit better now but it is still going crazy when I throttle up.

Maybe a faraday cage would be the solution

Nils

[EOSBandi]

Faraday cage wont be a good idea, it indeed does not let emf in but locks out earth's magnetic field also...

[KeesvR]

Here you can read something different as you say: http://en.wikipedia.org/wiki/Faraday_cage

I'm gonna try the faraday cage this week and let you all know if it works.

[KeesvR]

I have tried to get weird readings from the mag and i can't get bad results.
My mag is working to good to test the faraday cage, I'm sorry.
The only time when the mag goes bad, is when i hold a motor (magnet) close to the sensor about 5 to 10 cm.

Maybe this has to do with the ground, i use my frame as ground.
The thing you could try to do is make a ground cable in a circle under your sensor board, i don't know if this works but it's easy to do.

Some pictures of my grounded frame:

[jevermeister]

As you knoiw I twisted the wires LIPO->ESC and I did some flight testing now,

the mag only gets wild if I give a lot of throttle, In praxis this is connected to a really full speed rising maneuver.
So in a normal situation I do not have a problem with uncontrolled yawing in mag mode. I will keep an I on that and looking forward to position hold.

I wish I had the time to understand GPS code and help you guyes developing position hold...

[PatrikE]

I have same issue as jevermeister.
To hover works but increasing throttle over 3/4 will make it rotate.

Distance to closest ESC is ~8cm.
I will try to increase the distance or shield the board some way.

[zarkon]

nice setup you have there I have one Tri base on rcexplorer too but using KK board still rebuilding My MWC missing some header pin stopping my build