View Full Version : 1-st Aeroquad GPS Position Hold on JJ-copter Mk4 GPS Enhabled

12-20-2010, 07:24 PM
JJ-copter GPS POSITION HOLD MODE TEST (no RC trim apllied)


Quad: JJ-copter ver. Mk4
Test Pilot: My Nephew Johnny
Site: Castelvetere sul Calore (AV) - Italy

Based on:
Aeroquad SW: ver 2.0 modded
Configurator: 2.5
Board: Arduino Mega
Sensor: Wii WMP + Nunchuck
Compass: 2 Axis SURE Elect.

Frame Alluminium Slim Profile Dihedral Arms:
Alluminium arms, alluminium plate + 4 nylon screw to sustain Arduino and velcro for Wii sensor )

My main goal is to have smooth GPS position control joined with low oscillation easy control to alow in the next future the autonomous flight
The GPS is a SKYLAB SKM53 based on MediaTek 3327 Serial
The Stability is obtained using DCM also for YAW (the compass (only 2 axis 6 $) data are loaded into DCM
The GPS is integrated by a personal NMEA Parser. NMEA Message are interleaved with Wii sensor. radio and Compass at 2 Hz
The Position Hold has increased accuracy based on geostat. satellite EGNOS european Satellite Based Augmentation System (SBAS) (equivalent to U.S. WAAS )

The stabilitycontrol routine (enhanced vs. Mk2 and Mk3) is quite different from standard Aeroquad 2.01 wilst the Heading Hold use the old 1.71 version on DCM stabilyzed Euler angle

more on JJ-copter Mk2 Mk3 Mk4:

JJ-copter main Tread : http://aeroquad.com/showthread.php?1268-JJ-COPTER-MK2-STABLE-MODE-(MEGA-Wii-GPS-Compass)

On next pages you can find newer JJ-copter versions info and more videos


12-20-2010, 07:41 PM
Congratulations again ziojos, so many new achievements! Will it be hard for you to move the new features to 2.1 code?

12-21-2010, 12:42 PM
Really great!

What I wonder is: would you be able to do all this if you lost the quad totally? I mean, get new sensors and frame and everything, and just start over?
I'm wondering since it would be awesome if this could be done more or less to every hardware setup in AeroQuad.

12-21-2010, 03:24 PM
Great stuff!

Will the next step be combining the Altitude hold coding you wrote with this GPS hold coding to give you a full position hold?


12-21-2010, 07:39 PM
Thank a lot :)

Will it be hard for you to move the new features to 2.1 code?

It need a couple of day with test. I hope to do this in the next future with an optimized SW, actualy my is only a work in progress.


Why I have to lost my quad ? ;)

I use Wii only because when I started JJ-copter I took :cool: my nephew's WM+ and Nunchuck promising him to pilot the quad ;)

I'm considering the integration of my Altitude "Stabilizer" with GPS altitude (EGNOS in Europe, WAAS in U.S) to have autonomous flight. I know some time GPS give instable altitude but my test seem give good chance


12-29-2010, 07:30 PM
A very simple test of JJ-copter's GPS to comeback to home after a takeoff from different position


Only Throttle command on fly back



12-29-2010, 07:38 PM
Your work just keeps getting better! Really impressed with the progress you are making. I Can't wait to see what you come up with next.


12-29-2010, 07:44 PM
Nice nice!

Have you recorded the precision you can get out of your GPS unit? Like making graphs to compare real life position against what the GPS reads.

I've been thinking of making a local positioning system using 3 beacons to make for a trigonometry system to get much more reliable signals than GPS, but I have no idea what to use for hardware.

12-29-2010, 09:10 PM
JJ-copter GPS POSITION HOLD MODE TEST (no RC trim apllied)...Great Job.

01-16-2011, 01:58 PM
Nice work Ziojos!

04-10-2011, 09:23 PM

Compared to the previous movies

On GPS side:

Increased the update of GPS from 2Hz to 4Hz
Rewrite / Optimized GPS Control Routine

On the Fligth Control:

New JJ-Stable Mode with Anti Jiitter capability (COG compensation)
Main Control Loop speed 160 Hz (+/- 2 % dued to Sw interrupt) was 120 Hz

The GPS has increased accuracy based on Geostationary Satellites EGNOS

http://www.esa.int/esaNA/SEM98MUTLKG_egnos_0.html :)

The main result obtained is a good fligth smoothness

05-23-2012, 07:42 AM

This video is shooted from takeoff to landing with RTH ON ..... only throttle command :).

The weather was very windy with more than 5.5 m/s gusts on ground I think more (6-7 m/s) in the fly position

The max Attitude GPS Integral limiter was on 4m/s this stabilized the quad 6-7 mt away from the take off ;)

the altitude hold is swithed ON (by throttle in mid position) from 1:10 to 1:40

JJ-copter MK4.2 has New GPS (MTK3329 based) + MS5611 Baro On MWii 1.9 Framework same frame of MK4.0


07-19-2012, 09:37 PM
In this video is simulated a Fail Safe. In the firt time you can see an accurate GPS return to home from short distance with wind pushing to home.
then a RC power OFF and consequent landing controlled by GPS+Baro Position Hold and automatic motors OFF by Ultrasonic

The new Mk5 frame:
65 cm MtoM
240 gr
full CNC aluminium rectangular rods

The landing speed is programmed as the fastest safe speed
wind was 4 m/s