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de/Features/FailSafe








Info

The FailSafe-Function is an additional safety feature for the MikroKopter.
If there is a loss of the receiving signal the Kopter will not crash with the correct set up functions,
but flies back automatically into the direction of the Homeposition (Start position) and also into the range of receiving.

Important:

So that you can use this function the used receiver must display the loss of the received signal.

Wether the used receiver is indicating that you can determine easily as follows:

If the transmitter will be switched OFF now:

  1. the red LED on the FlightCtrl must light and

  2. the buzzer must give a warning signal as you can hear here: (Audition reception failure).

After you switch the transmitter ON again the warning signal disappears and the red LED is OFF.

If this case you can use the FailSafe after some settings that are described below.

IMPORTANT

Before using the FailSafe-Function it is necessary that the user clarifies wether such a mode of operation is permitted in the country / to the respective site or by legal, insurance or other terms.

The FailSafe-Function can be used only if a GPS-System is available on the Kopter and a Sat-Fix is present!

The function

A loss of a signal can have different sources. You fly out of the range of the transmitter/receiver or the battery has a low voltage and fails, etc.

If the MikroKopter detects a loosing signal the FailSafe-Function will be active for the time you set under "Failsafe CH time" (Link). In this time the following functions will run:





If the 60sec. are used up because of a to great distance or altitude to the homepoint, the pre-defined "EMERGENCY-Gas/Throttle" will be switched on automatically.
The Kopter will go into a descent with the set up values for "EMERGENCY-Gas/Throttle Time" and "EMERGENCY-Gas/Throttle".

IMPORTANT

If no "Failsafe CH time" has been entered in the settings, the Kopter will directly go down with the emergency-gas and emergency-time settings

Security

Failsafe with reception failure at the start point will be suppressed if the throttle stick has been on ZERO for about 1,5 seconds before (40m radius and 15m altitude). It will be switched now to Min-throttle instead.
That should cover the following scenario: The MK will be landed close to the start place and the pilot switches off the transmitter accidentally (the motors are still running). In older versions the MK started again under circumstances.

The settings

http://gallery3.mikrokopter.de/var/albums/intern/MK-Tool/Setting/Misc/EN_Misc-FailSafe.jpg?m=1516616135

INFO: The settings can be found in KopterTool under the tab Misc.

If the tab is not visible you have to activate the Expert view.

To use the "FailSafe"-Function you need to set this 3 Step's:

Step 1

Setup of the FaliSafe Altitude.

The altitude can be entered in the settings under "Misc" -> "FailSafe Altitude":
(INFO: if you use an older software the "ComingHome altitude" (set under "EasySetup") this altitude is also the FailSafe altitude)

Here you can enter the altitude in which the Kopter, in case of a lost signal, flies back.
This altitude will be used not to fly into i.e. houses, trees, bushed etc. during an automatical back flight.

Step 2

Setup of the Failsafe CH time.

This "FailSafe"-Time will be entered under "Failsafe CH time" (adjustable to observe legal regulations).

In this setting you enter the time for the Kopter which is maximal available for the function "FailSafe".
User without license can enter here "60" for max. 60 Seconds.
With license you can enter here up to 254 (seconds) or disable the limit with 255.
During this time the copter flies back to the home position.

Step 3

http://gallery3.mikrokopter.de/var/albums/intern/MK-Tool/Setting/Misc/EN_Misc-Notgas.jpg?m=1516608196

Setup of EMERGENCY-Gas/Throttle Time and EMERGENCY-Gas/Throttle.
(is active after the FailSafe time is over)

(!) For information: The whole Emergency-Gas/Throttle-regulation will be only active if a gas/throttle value of >40 and for at least 4 seconds has been exceeded, that means the Kopter probably flies!

If the "FailSafe"-Time has been elapsed and the Kopter is still in the air the EMERGENCY-Gas/Throttle Time and the EMERGENCY-Gas/Throttle will be active.
This setting works also immediatly if no "ComingHome Altitude/height" has been entered.

Point 1: EMERGENCY-Gas/Throttle Time
The "EMERGENCY-Gas/Throttle Time" determines the term of the EMERGENCY-Gas/Throttle function. After that time the engines turn off automatically.
Here you can enter maximal "247" = 24,7 Seconds.

Point 2: EMERGENCY-Gas/Throttle
Here you can set the speed for the descent flight of the Kopter.
(Only valid for the "EMERGENCY-Gas/Throttle"-function, not for the function "FailSafe". Here the speed for the descent flight will be determined automatically.)

You can enter here either way a fixed value which depends on the weight of the Kopter. That must be determined before.
Or you use the "Automatic" and activate the entry "Use vario control for failsafe altitude".
ATTENTION: If you activate this entry a percent-sign (%) appears before the entry "EMERGENCY-Gas/Throttle".

Now you can enter here a percent value of the needed hovering-gas/throttle. If you enter here a "100" for 100% the Kopter would hover instead of turning into a descent flight.
A little bit smaller value should be entered here.
ATTENTION: The smaller the value the faster descent the Kopter. With a value i.e. of 80% the Kopter comes down pretty quick.




Landing speed in failsafe case

Since firmware-Version FC 0.91 you can set under Altitude a landing speed for auto-landing. This landing speed is also used for emergency landing in failsafe-case (RC-Lost).

example setting

http://gallery3.mikrokopter.de/var/albums/intern/MK-Tool/Setting/Altitude/EN_Altitude-Landingspeed.jpg?m=1500542003

Procedure in the case of failsafe is:

This procedure above may take 60 second (what you set as failsafe-time). After this time the MK uses the "emergency-gas" for the set time:

If the RC-Signal comes back within the procedure, the failsafe is cancelled an the MK is back under RC-control.

FailSafe Channel

http://gallery3.mikrokopter.de/var/albums/intern/MK-Tool/Setting/Misc/EN_Misc-FailSafe.jpg?m=1516616135

The function Failsafe channel can be used for two Applications.

Application 1: FailSafe testing - simulating a reception failure

The FailSafe function will normally only work when the signal between transmitter and receiver is lost.

This can e.g. happen when:

To test the FailSafe function you must have an reception failure.
But for this you please NEVER switch off your transmitter !!!

Quick and easy you can test it with the "Failsafe channel".
So you can terminate very fast the reception failure and get back the control over your copter.

To use this you need:

On your transmitter you will now program this free channel to the free 2-way switch.
Set this channel then under "Failsafe channel".



The function is now:

Test on the ground:



So you can now quickly and easily interrupt the reception and start the function FailSafe.
The copter will then do as described under "The function".
Should then happen something unexpected (e.g. in the flight path is suddenly a tree ;-) )
you can switch off the function and get beck immediately the control.






Application 2: unsuitable receiver

http://gallery3.mikrokopter.de/var/albums/intern/MK-Tool/Setting/Misc/EN_Misc-FailSafe.jpg?m=1516616135

<!> You need this function only if you use a receiver who will not display the loss of the received signal (see above).

So if you switch "OFF" the transmitter and you do not hear a warning signal from the copter and there is no red LED on the FlightCtrl, the receiver will not send a "warning signal".

In this case you please do this:

Set this free channel under Failsafe channel.

Here the selected channel must then be set so that:

(The exact settings are described in the instruction manual of the appropriate receiver/transmitter or information will be given by the manufacturer.)


see also: Firmware-0.86


DocWiki: en/Features/FailSafe (zuletzt geändert am 13.04.2021 08:45 durch LotharF)