Loss Link (MikroKopter FailSafe) 

Procedures & Electronic Parameter Settings
en/FailSafe

28

LotharF

MikroKopter.de
Inhaltsverzeichnis

1 Prolog...........................................................................................................................................................1/10

2 The function.................................................................................................................................................2/10

3 Security........................................................................................................................................................4/10

4 The settings..................................................................................................................................................5/10

4.1 Step 1............................................................................................................................................5/10

4.2 Step 2............................................................................................................................................5/10

4.3 Step 3............................................................................................................................................6/10

4.4 landing speed in failsafe case........................................................................................................7/10

5 Video of the FailSafe...................................................................................................................................9/10

6 FailSafe Channel.......................................................................................................................................10/10

en/FailSafe

i
1 Prolog

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:

• Receiver is connected to the FlightCtrl.

• Transmitter and FlightCtrl (copter) are switched ON (supplied with voltage).

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 asyou can hear here: Link.

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!

1/10
2 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 maximal 60 Seconds with

the following functions (from version V0.88 FlightCtrl):

(This time you can enter under "Failsafe CH time": Link.)

First at all the function "PositionHold" will be activated for 5 seconds and the Kopter climbs/falls to

the preset "ComingHome Altitude". (note: only if the distance from the starting point is >25m)

• 

After the 5 seconds the function "ComingHome" will be automatically activated and the Kopter flies

back into the direction of the Homeposition (Start Point).

(If the set altitude shouldn't have been reached within the first 5 seconds increases or decreases the

Kopter its altitude during the flight back.)

• 

• If the signal restores again a normal control is possible.

If the signal is not restoring at that time the Kopter will fly back to the Homeposition, goes down and

tries to land (see below 'landing speeds').

• 

• For the way back and the descent to the Homeposition the left over 55 seconds are available.

• 

2/10
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

en/FailSafe 02/03/15 23:04:34

3/10
3 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.

4/10
4 The settings

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

4.1 Step 1

Setup of the ComingHome 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.

The altitude can be either way entered in the settings under "EasySetup":

or under the tab "Navi-Ctrl 2":

4.2 Step 2

Setup of the Failsafe CH time.

In this setting you enter the time for the Kopter which is maximal available for the function "FailSafe".

As a maximal used time you can enter here "60" for 60 Seconds.

(You can enter also a higher number but only the maximal value of "60" will be stored.)

This "FailSafe"-Time will be entered in the tab "MISC":

5/10
4.3 Step 3

Setup of EMERGENCY-Gas/Throttle Time and EMERGENCY-Gas/Throttle.

 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.

en/FailSafe 02/03/15 23:04:34

6/10
INFO

User with a commercial license should activate in the settings under "MISC" the entry "SD card missing - no

start without SD card".

If a SD-Card is not plugged in or got loose the extended functions couldn't be used.

In that case the Kopter wouldn't start.

4.4 landing speed in failsafe case

Since firmware-Version FC 0.91 you can set a landing speed for auto-landing. This landing speed is also used

for emergency landing in failsafe-case (RC-Lost).

example setting

Procedure in the case of failsafe is:

• go to CH-Altitude (defined in the sample to 30m) and stay for 5 seconds on that position (PH)

• fly home (usually the speed is 7-8m/sec)

• at home point go down:

en/FailSafe 02/03/15 23:04:34

7/10
♦ descend 4m/sek until altitude of 20m

♦ descend 2m/sek until altitude of 10m

♦ use the 'landing-speed-Setting' for the last 10m for descending

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:

• motor to emergency-gas for the selected time (in my example 85% hoovergas for 9 seconds)

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

RC-control.

en/FailSafe 02/03/15 23:04:34

8/10
5 Video of the FailSafe

 ATTENTION: PLEASE DO NOT IMITATE! If you switch OFF the transmitter the Kopter is inevitably

NOT UNDER CONTROL and can crash! To switch ON the transmitter can take a few seconds.

9/10
6 FailSafe Channel

 You need this function only if the receiver do 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:

Receiver without an indicator for the loss of a received signal:

Since Softwareversion V0.88 (FlightCtrl) you can use also a receiver for the FailSafe (and

Emergency-Gas/Throttle) which is not displaying the loss of a signal.

This requires two conditions.

1. You need a free channel on your transmitter

The receiver / transmitter have an own "Failsafe" (see manual of the receiver/transmitter).

(It has nothing to do with the "FailSafe" of the MikroKopter)

2. 

Set this free channel in the settings of the KopterTool under "Misc" Link.

• 

Now you have to set the Failsafe or the receiver/transmitter.

There you can assigned a value for each channel of the transmitter.

The appropriate channel must be set up in that way that it is switched ON during operation and switched OFF

during a signal failure.

(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

10/10
en/MK-Parameter/Misc

13

LotharF

MikroKopter.de
Quick selection

Open the description -> click Button

This page as an PDF-Document?

Click on that Symbol and wait a little moment... --->

Misc

• deutsch

en/MK-Parameter/Misc 02/03/15 23:29:35

1/7
In these settings for example additional features such as CareFree or Emergency-throttle can be set.

en/MK-Parameter/Misc 02/03/15 23:29:35

2/7
Min. Gas

Minimal gas value, which goes to the motor.

• 

Max. Gas

Maximal gas value which goes to the motor.

• 

Compass effect

Is a compass connected the influence of the yaw can be set up here. In that case a small number has a

small, one large number has a big influence.

• 

Carefree control

Is the value "0" the function CareFree is off. To toggle the function at the transmitter you can set up a

channel.

• 

Under voltage

The threshold is set in 0.1 V steps to report the battery-low voltage.

The default setting is 33 (3.3 V). This is the voltage of each cell in a lipo that should not be exceeded.

(Infos about the Lipo you can read here: Lipo)

When you turn on the Kopter it will detect automatically if, for example, a 3S or 4S Lipo is

connected.

Info: After switching on (1 x a slightly longer beep) is heard, the detection of cells: 3S = beep 3x, 4x

beep = 4S; ...

 If the under voltage limit is reached, a battery warning issued over the Summer. IF you hear this

warning, the Kopter should be landed.

If you set a wrong under voltage limit (maybe to low), you will hear the warning until this (wrong)

voltage.

• 

en/MK-Parameter/Misc 02/03/15 23:29:35

3/7
Are the cells (it already reaches 1 cell) then lower then 3V, the performance may decrease abruptly.

CH voltage [0.1V]

Here you can set the voltage where the copter should automatically fly back to the home position.

Important The voltage should be less or equal than the Under voltage.

• 

Autoland. voltage [0.1V]

Here you can set the voltage where the copter should automatically land.

Important The voltage should be less or equal than the Under voltage.

• 

Voltage reference

 Normally you do not have to change this!!

This setting is only for a few FlightCtrl V2.1 at the beginning who get's a other voltage regulator.

With this you see in the KopterTool a lower voltage then it realy is. Here you can adjust this. More

informations about this you can find here : UndervoltageSettings

• 

Loss of receiving :

INFO:

The emergency gas is only active when a gas value was >40 for at least 4 seconds. This means the

copter is flying!

If the copter stay on the ground, you start the motors and switch off the transmitter, the motors will

stop immediately and the function emergency gas is not working!

• 

Emergency Time [0.1s]

Here the time is entered in tenths of seconds for which the gas is actively seeking emergency

reception failure. As a value, a number 1-247 can be entered.

So it is a maximum time of emergency-throttle/gas (247 x 0.1s) 24.7 seconds possible.

• 

Emergency-Gas

With this emergency gas value the copter goes into the descending flight when a) the time for the

FailSafe is over or b) FailSafe is not set/enabled.

For the emergency gas there are two possibilities:

Automatic

If you activate Use vario control for failsafe altitude a percent sign appears before the input

field emergency gas. Now you can set the emergency gas as a percentage value. Now the

needed emergency gas will be calculated automatically - no matter how heavy the copter is.

Applies here => 100 = 100% = Copter hovers / keeps the height.

IMPORTANT: The function Vario altitude control must be the selected under the tab

Altitude.

♦ 

Manual setting

Depending on the total weight of the copter emergency gas and the settling velocity can be

♦ 

• 

en/MK-Parameter/Misc 02/03/15 23:29:35

4/7
entered individually.

The value should not be set too low or too high. Otherwise the copter can fall to fast down or

climb into the sky if the signal is lost.

(See below under Obtaining Emergency-gas values)

INFO: The set value (Manuell or Automatic) should be chosen so that the UAV to quickly lose

altitude. Decreases the copter too slow, the emergency gas time can flow during the fall and the

engines put off!

FailSafe CH time

In case of RC transmission-lost the MK will fly now automatically for 60 sec. to the Home-Position.

(Commercial users can determine up to 247 Seconds.)

The function and settings of the FailSafe themselves are described here: FailSafe

• 

!Failsafe channel

If a receiver is used which is not showing a receiving failure a loss of the received signal will be not

detected and the Kopter would continue to fly with the last received settings.

Here you can enter a free channel. This channel must be set over the "!Failsafe" of the receiver so that

the channel is switched off during a loss of a received signal.

Is that channel available on a button at your transmitter you can use actually that button as a

test-button for the function "!Failsafe".

• 

Error-Beep (No beep without active transmitter)

If you power on your Kopter and the transmitter is not switched on, the Kopter give you a beep signal.

This beep signal will stop if you switch on the transmitter.

After activating this function, the copter will not beep after you power on the Kopter and forgot the

transmitter.

(The signal loss is still displayed)

• 

Use vario control for failsafe altitude

If this function is enabled, a percent sign appears in front of "emergency gas" (%).

See above => emergency gas > Automatik

• 

Compass error

NOTE: This function should only be used for testing purposes!

If you click here "ignore magnet error at startup" magnet failure messages will be ignored which are

avoiding a start of the Kopter.

When using this function a flying with GPS function (PositionHold, ComingHome, CareFree) is

expressly not recommended. Existing magnetic errors can affect the flight and cause a malfunction of

the compass.

This can lead to the crash of copter.

• 

SD card missing

If you click here "not start without SD card" the Kopter will start only with the insert SD-Card.

If the card is missing the motors can be maybe started. But then a lift of / increase of the engine speed

is not possible.

That can be necessary for the commercial use of the Kopter if certain legal requirements are

requested.

(i.e. range limit, Emergency program within an unforeseen exit of a prescribed radius, etc.)

(see also: FailSafe)

• 

GPS fix missing

If you click here "not start without GPS fix" the Kopter will only start with a made Sat-Fix.

If the GPS fix is missing the motors can be maybe started. But then a lift of / increase of the engine

speed is not possible.

Without a Sat-Fix the GPS-Functions like PositionHold, ComingHome or FailSafe are not possible.

To ensure that the GPS functions can be used you can activate this function.

• 

en/MK-Parameter/Misc 02/03/15 23:29:35

5/7
Info:

This Emergency-Gas function is used at your own risk. In the event of a loss of reception the Kopter

may come down with a sink rate defined here.

The Kopter comes down there where the loss was of the reception. Damage to the MikroKopter can

not be ruled out!

 To display this feature, the receiver must receive the loss. This can easily be checked:

- Receiver is connected to FlightCtrl. Transmitter and FlightCtrl are switched on (powered).

- Now, the transmitter is turned off the red LED lights on the Flight-Ctrl. and the buzzer gives a

warning signal.

If there is a loss of reception (e.g. from out of range or transmitter off), the gas emergency regulation

becomes effective.

Find the right emergency gas value for manual emergency gas:

On an open field with plenty of space, the required emergency gas value and the function can be

flown easily tested.

To read the values??, perhaps, a second person could be there and help.

 You can store different emergency gas levels in the various settings !!!

 If, for example, a camera is carried later on the MikroKopter the UAV is heavier and therefore it

must be another/different Emergency-gas time adjusted !!!

The easiest way to determine the needed gas value is in the KopterTool. This should include a data

link between the MikroKopter and the PC ( or laptop) to see the data in KopterTool.

This can be done over a Bluetooth modul or a Wi232 modul (Link).

If the connection is available you can change in the Kopter-Tool into the following display (with the

red arrows):

Now the Kopter can be started and you can hover in a height of approx. 15 - 20mtr (or higher). All

additional features such as height, PositionHold, etc. are off.

The value now displayed next to Gs: is the gas float value.

Now, the gas can be reduced slowly so that the MikroKopter falls. If you have a proper rate of descent

and if this value is reached, the value can be read next to Gs:.

This value can be entered now as emergency-gas.

If the value is entered and stored in the !Flight-Ctrl. the MikroKopter can hover in the air and you can

turn off the radio once.

• 

en/MK-Parameter/Misc 02/03/15 23:29:35

6/7
The copter should come down now with the emergency gas setting and shut down after the set time,

the engines.

en/MK-Parameter/Misc 02/03/15 23:29:35

7/7