Helicopteros Radio Control - RC - Radiocontrol

Hi,

Just some precisions about the current 
GPS
 dev code:

[U]1) hardware setup:
[/U]
An arduino mega (might change in the future for a promini, but not yet) with the 
GPS
 connected on serial port 2 (customizable, but with the typo correction just mentionned by PatrikE). I'm currently using the flyduino MEGA.

You must configure the right baud speed of the 
GPS
 port according to your 
GPS
 device. (#define 
GPS
 + #define GPS_SERIAL 2 + #define GPS_BAUD 115200)

You need a NMEA 
GPS
 compatible (most serial 
GPS
 are compatible). Currently multiwii does not configure the 
GPS
 device (will change in the future). So your 
GPS
 device must be already configured to output these frames. A 5 or 10Hz is preferable. This update rate is not configurable inside multiwii, multiwii takes what it receives. I'm now using the 10Hz FMP04 
GPS
 with the 
GPS
 BOB from flyduino.

All the sensors GYRO+ACC+MAG are mandatory. Your multi must be perfectly tuned in level and heading (mag) mode. Your mag direction should not be altered by running motors (this point is very important). Your MAG arrow must point the north direction.

Baro is not mandatory, but a working baro config in preferable.

[U]2) visualization
[/U]
If the 
GPS
 is correctly connected and configured. You should see the 
GPS
 blinking in the GUI (around the grey rosace N/S/E/W in the GUI) according to its update rate.

A specific Status LED blink pattern occurs when motors are disarmed and once a fix is ok.

Once a fix is ok, you should see the number of satellites and the distance to the first fix position (home) in the GUI.

[U]3) activating the 
GPS
[/U]
The 
GPS
 must be activated (via checkbox and AUX configuration) only if a fix is ok. The home will be set with the first fix.

The 
GPS
 can be only activated if level mode if also activated. (MAG mode activation or BARO mode activation are not mandatory)

The current implementation only supports Return To Home function (PH will be easy to add)

Once activated, the 
GPS
 will rely on 3 parameters to work
distance to the target point (calculation obtained from 
GPS
 device)
absolute direction to the target point (calculation obtained from 
GPS
 device)
heading direction (calculation obtained from MAG+ACC device)

The target point distance is used to determine an angle inclination.
A PID has been added to the GUI, but it's not currently a real PID.
P is used to tune the proportion of inclination regarding the distance to the target point.
I is not used
D is used to limit the max inclination

The combination of direction to the target point+heading direction is used to apply a mix on the motors to follow the right direction.
														[URL=http://www.multiwii.com/forum/memberlist.php?mode=viewprofile&u=53]Alexinparis[/URL]