Do you have an Ardupilot Mega and shield and want some fun for little money? check this tiny quad... my last drone in family...
Some specs:
- Size : 26.5cm (10.4 inches) from motor to motor
- Motors : 18-11 200kv 10 gram motors
- Props : 4x2.5 (standard CCW props)
- ESCs : Turnigy 6A
- Battery : 3S610 (or 3S800)
- Sonar : Maxbotics LV-EZ0 [optional]
The nice part about this frame is that it use standard kite parts, so it´s very easy to construct and it´s perfect for some radical tests.
Itried to find a bit different design that also make the quad less simmetrical (it´s very easy to loss the orientation with a quad) and I wanted to do as small as posible to flight indoors...
At this size and weight it´s very safe and robust also. The props use prop savers and this help a lot in crashes...
I am not very good writing... so I took a lot of photos during the build phase and I created a build log: https://docs.google.com/document/d/1fIZL-Ca2fx2RPhBQLzoOdqdCuikXRKePwKbxDlJWiss/edit?hl=es
This code supports a sonar for altitude hold and also has a battery alarm (2 alarms).
Thisquad works with ArduCopter code, but because how main board is mounted, actual code doesn´t work. This is the code that I used with this quad :
http://code.google.com/p/arducopter/source/browse/#svn/branches/Arducopter_indoor
(as zip format: Arducopter_indoor.zip )
note that this will be integrated on main Arducopter code. Now is temporarily in a branch.
ThePID gains are different than in standard ArduCopter, so you need to Initialize EEPROM on Configurator or put this ones manually:
-Stable mode: P : 4.8 ; I : 0.12 ; P_rate (D in configurator) : 0.4 ; Yaw : (4.5 ,0.15 ,2.8 )
-Acrobatic mode : P : 0.75 ; I : 0.1 ; D : 0 ; Yaw : (2.4 ,0.2 ,0 )
OK, but was all so perfect like in the video? I don´t believe that...
Yes, you are right, but fortunately this design is very crash resistance... and this part is also fun...
After all this battles I only needed a few drops of ciano in the crash with the lamppost :-)
What´s the real size?
On center, standard arducopter frame, on left, old ArduIMU quadcopter part III, on right-top this project.
And what about the automatic aerobatics on video?
I am starting to test a new function to do automatic aerobatics (Automatic Aerobatic Procedure). The idea is that you enable this function with a switch in the Tx to make an automatic predefined aerobatic and then automatically recover to a stable mode.
Thisis actually a proof of concept but works very nice. One limit here is the maximun rate of the gyros, in our case 500deg/s. If we exceed this, the IMU get confused...
An interesting point to note is that the IMU doesn´t loose the orientation in this hard movements...
Thestory is that I have never feel too much confidence doing flips manually with quads. Then I start thinking that with an automatic code we can get a precise timing and controled movement so maybe this could help to do better aerobatics. I started testing this function outdoor, on an open field but I was improving the code and got more tightly maneuvers, so tight, that I ended up doing flips with a quad inside my room!!!
Here is the code I was testing : (AAP function: AAP.txt )
I implemented this functionality as a state machine where there are three kind of states:
- fixed commands for a limited period of time. (example : Apply a throttle command)
- fixed commands until we reach some IMU state (example : roll until we reach a certain angle)
- And a mix between this categories and a control (example : Throttle command + stable mode on roll, pitch, yaw)
There are many things to test and improve here but the basic concept works very nice...
If I can get a bit of help from a friend, I will probably made a carbon fuselage for this prototype...
Enjoy this “Science & Fun” mix...
Jose Julio.
Arducopter Team
Comments
@Mathew, tilted motors also work on big quads, but is a less efficient setup for a quad (some force is used to compensate torque) and quad is not so "simetric" but works fine. If you can get CCW and CW props is better to go for it...
I have give you edit permission to the google doc build log document, please feel free to add your fantastic drawings...
If someone more wants to edit the build log document please send me an PM and I give you edit rights.
Thanks Dave.
1- All the Esc in parallel, so all blacks wires together and all red wires together. Red wires got to the battery red wire and black wires go to de battery black wire ¿is it right?. If so, what connector are yor using between ESCs and battery?, in the photo seems like a T-Dean but with one of the pinnes missed.
2- To feeding the APM board, you take from any ESC a red wire (Vcc) and a black wire (GND) and both go directly soldered, with no connectors, to the AMP borad. So, I understand we are feeding the board with 12 volts !!!! is it right?
Thanks