AttitudeControl (Lagestabilisierung)

Bitte beachte, dass die AttitudeControl (Lagestabilisierung) ein optionales Feature ist. Die zugehörigen Menüpunkte können nur ausgewählt und aktiviert werden, wenn die AR7210BX PROEDITION Firmware auf dem Gerät installiert ist. Dieses optionale Update kann über den freakware Webshop gekauft und dann mit der StudioX Software/App auf das Gerät aufgespielt werden.

Was ist eine AttitudeControl und wie verwendet man sie?

Im Prinzip ist die AttitudeControl eine Lagestabilisierung, die den Heli auf Knopfdruck in in die Schwebeposition bringen und dort halten kann. Hierbei gibt es verschiedene Möglichkeiten, wie sich das im Detail auswirkt. Die Art der Stabilisierung lässt sich im PARAMETERMENÜ auswählen.

Stabilisierungsmodi

• Quadmodus
  

In diesem Modus fliegt der Heli ähnlich wie ein Multicopter. Das Pitch kann "ganz normal" gesteuert werden, aber wenn man Roll oder Nick betätigt, dann wird der Heli nur um einen bestimmten Winkel gekippt, nicht hingegen mit einer bestimmten Geschwindigkeit gerollt. Das erleichtert das Helifliegen enorm, denn der Heli kann nicht in eine "schwierige Position" gebracht werden, der maximale Kippwinkel wird durch den maximal möglichen Steuerknüppelausschlag begrenzt. (Hinweis: wenn Du im Quadmodus auf dem Rücken schweben willst, dann musst Du die Stabilisierung ausschalten, um den Heli umdrehen zu können, und dann erst in Rückenlage zuschalten).

• Rettungsmodus
  

Beim Zuschalten des Rettungsmodus wird der Heli zurück in die Schwebeposition gebracht, z.B. wenn Du die Orientierung verlierst. Dabei ist es völlig egal, wie der Heli gerade fliegt, senkrecht oder auf dem Rücken, er wird immer in die (einigermaßen) sichere horizontale Lage gebracht, so dass Du wieder die Kontrolle übernehmen kannst. Wenn Du "Rettung mit Pitch" verwendest, dann kontrolliert das System sogar das Pitch, so dass der Heli auch in vertikale Richtung mehr oder weniger stabil steht. Oder Du verwendest diese Funktion dazu, dass der Heli schnell an Höhe gewinnt, weit weg vom Boden (um dies zu erreichen kannst Du aber auch die Funktion "Rettungsboost" über die StudioX Software oder StudioXm App aktivieren, die einen zusätzlichen kurzen Pitchstoß gibt).

• 3D - Modus
  

Dieser Modus funktioniert fast genauso wie der Rettungsmodus, nur mit dem Unterschied, dass der Heli sowohl in normaler wie auch in Rückenlage stbailisiert wird. Das System erkennt, welche Lage näher zu erreichen ist und hält den Heli dort, ohne ihn komplett umzudrehen. Das ist von Vorteil, wenn man (3D) Kunstflugmanöver üben will, z.B. Rückenflug, Überschläge oder TicTocs. Da man die AttitudeControl immer durch Steuerknüppeleingabe übersteuern kann, bietet sich sogar die Möglichkeit, diese Funktion für einen längeren Zeitraum eingeschaltet zu lassen. So kann man z.B. einen Überschlag üben und sich vorerst nur auf das saubere Aussteuern von Pitch konzentrieren, während Nick- und Roll nicht so präzise gesteuert werden müssen. Wenn de Heli einmal über 90 Grad nach vorne gekippt wurde, so wird die AttitudeConrol den Heli nun weiter in Richtung Rückenlage ziehen und dort halten, ähnlich wie ein Fluglehrer oder Copilot. Zu beachten ist, dass der Heli im 3D - Modus nicht stabilisiert wird, solange er genau senkrecht steht! Durch dieses Feature fällt das fliegen und üben leichter, während die AttitudeControl ständig zugeschaltet ist.

Neben der Wahl zwischen diesen fünf Modi (Quadmodus, Rettungsmodus, Rettung mit Pitch, 3D - Modus, 3D - Modus mit Pitch) bieten sich noch weitere Möglichkeiten, die AttitudeControl über die StudioX Software oder StudioXm App an Deine Vorlieben anzupassen. So kann z.B. der Rettungsboost aktiviert werden, der dem Heli für einen kurzen Moment in die Höhe steigen lässt, oder Du kannst den Pitchsteuerknüppel sperren lassen. Diese Optionen werden weiter unten im Detail erklärt. Ausserdem bietet die Bankumschaltung (Flugphasenumschaltung) die Möglichkeit, während des Fluges zwischen unterschiedlichen AttitudeControl Modi und Einstellungen zu wechseln.

AttitudeControl während des Flugs zuschalten

Separater Schaltkanal

Im Normalfall wird ein freier Schaltkanal am Fernsteuersender verwendet, um die AttitudeControl Funktion im Flug ein- und ausschalten zu können. Wird dieser Schaltkanal in eine Richtung bewegt/geschaltet, dann ist die Funktion aus, wird in die andere Richtung geschaltet, dann aktiviert sich die AttitudeControl/Lagestabilisierung. Hier bestimmt die Höhe des Steuerausschlags wie stark das System versucht, den Heli in die Neutrallage zu bringen und dort zu halten bzw. wie schnell sich der Heli in die Ausgangslage dreht und wie schwierig es ist, das System zu übersteuern. Auf Seiten der Fernsteuerung wird also ein Schalter benötigt, der einen freien Steuerkanal in beide Richtungen betätigen kann (welcher Kanal das ist, wird bei der Funktionszuweisung im EMPFÄNGERMENÜ bestimmt!). In der Schaltposition "Stabilisierung aus", macht der Steuerkanal einen negativen Ausschlag, z.B. -100%. Wenn Du den Schalter umlegst, wird der Kanal in die andere Richtung bewegt und dadurch die AttitudeControl zugeschaltet. Hier sollte der Steuerkanal nicht den vollen Ausschlag machen, sondern nur z.B. 50%. Dann wird die AttitudeControl mit 50% Wirkstärke arbeiten. Der genaue Prozentwert kann später erflogen werden, 50 sollte für den Anfang gute Ergebnisse liefern. Wenn das System nicht so stark reagieren soll und leichter zu übersteuern sein soll, z.B. wenn man den 3D - Modus verwendet und über einen längeren Zeitraum mit aktiver Stabilisierung fliegt, dann wird man den Wert möglicherweise eher reduzieren, z.B. auf 30%. Wenn das System den Heli hingegen sehr schnell und abrupt stabilsieren wollen, dann werden höhere Werte, z.B. 60% sinnvoll sein. Für den Anfang sollte der Wert aber nicht allzu hoch sein, da eine sehr hohe Wirkstärke unter Umständen eine extrem abrupte und heftige Reaktion des Systems verursacht, stärker als es der Heli u.U. aushalten kann!

Immer wenn eine Änderung auf dem Steuerkanal für die AttitudeControl stattfindet, z.B. wenn diese ein- oder ausgeschaltet wird oder sich die Höhe des Steuerausschlags ändert, wird der Status der AtitudeControl über die Menü LEDs angezeigt. Zur Unterscheidung von der Heckgyro-Empfindlichkeit leuchtet während der Anzeige des aktuellen AttitudeControl-Status die Status LED rot. Wenn die AttitudeControl aus ist bzw. ausgeschaltet wird, so blinkt die Menü LED A. Falls eine der LEDs B – N aufleuchtet, dann ist die AttitudeControl eingeschaltet. Die einzelnen LEDs signalisieren dabei die Wirkstärke der AttitudeControl. Je größer der Ausschlag des Schaltgebers/Kanals für die AttitudeControl ist, umso weiter wird die Menü LED beim Verstellen in Richtung Punkt N wandern und desto stärker wird die Wirkung der AttitudeControl. Stell im Sender die Höhe des Steuerausschlags so hoch ein, dass die Menü LED neben Punkt G leuchtet, wenn der Schalter für die AttitudeControl gezogen wird. Wenn der Schaltgeber in die andere Richtung betätigt wird, dann sollte die LED neben Punkt A aufleuchten und blinken. Die AttitudeControl ist dann ausgeschaltet. In diese Richtung ist es übrigens egal, wie groß der Steuerausschlag ist, da nur das Vorzeichen des Ausschlags dafür entscheidend ist, ob die AttitudeControl an oder aus sein soll.

Menü LED	A (blinkt)														B	C	D	E	F	G	H	I	J	K	L	M	N
AttitudeControl Wirkstärke	-														8%	16%	24%	32%	40%	48%	56%	64%	72%	80%	88%	96%	100%
Steuerweg Zusatzkanal	-100	-96	-88	-80	-72	-64	-56	-48	-40	-32	-24	-16	-8	0	8	16	24	32	40	48	56	64	72	80	88	96	100
AttitudeControl Status	aus														an

Programmierbeispiel einer Spektrum Fernsteuerung

Einen Schalter dem AttitudeControl Kanal zuweisen (hier Aux2 bzw. Kanal 7)...	... wir verwenden zum Beispiel Schalter H	Im Servomonitor siehst Du, wie der Schalter den Kanal steuert. +100% = AttitudeControl an
-100% = AttitudeControl aus	Falls notwendig kannst Du die Schaltrichtung ganz einfach mit der Funktion Servoumkehr vom Sender umdrehen	Stelle für den Anfang den Steuerausschlag in der Richtung wo die AttitudeControl an ist auf 50%. Damit ist die Wirkstärke der Lagestabilisierung auf 50% begrenzt.

Gyro channel (combined switch mode)

As an alternative to using a separate channel for activating the AttitudeControl you can also use the gyro gain channel, i.e. when you only have a 6-channel transmitter or when using a receiver with standard wiring (here we simply can't connect an additional channel physically). The activation of AttitudeControl will work quite similar as described above for the separate switch channel. Moving the channel into one direction will activate the AttitudeControl and the amount of deflection of the channel determines the stabilization gain, when moving the gyro channel into the other direction the leveling is disabled. But additionaly here the gyro gain channel also still adjusts the gyro gain. Precisely this happens when the channel is moved in the direction where the leveling is disabled. Here the amount of deflection adjusts the gyro gain and sets the gyro into heading lock mode. So for example you would assign a switch to the gyro gain channel and adjust the throw into one direction to let's say -50% and in the other direction to +60%, resulting in a gyro gain of 50% and a stabilization gain of 60%. By flipping the switch you can activate/deactivate the AttitudeControl instead of toggling the tail gyro between "Normal-Rate" and "HeadingLock" mode. The gyro gain value of -50% will be saved internally when switching into positive direction.

Menu-LED	N	M	L	K	J	I	H	G	F	E	D	C	B	A	B	C	D	E	F	G	H	I	J	K	L	M	N
Tail gyro gain	100%	96%	88%	80%	72%	64%	56%	48%	40%	32%	24%	16%	8%	0%	last value
AttitudeControl gain	-														8%	16%	24%	32%	40%	48%	56%	64%	72%	80%	88%	96%	100%
Auxiliary channel	-100	-96	-88	-80	-72	-64	-56	-48	-40	-32	-24	-16	-8	0	8	16	24	32	40	48	56	64	72	80	88	96	100
AttitudeControl Status	off														on

In the transmitter's gyro menu we assign a switch to control the gyro channel (channel 5).	When the switch is released we can set the tail gyro gain. As starting point we use 50% gain (=50% deflection).	When we pull the switch for AttitudeControl the channel is moved to the opposite direction. Here we set -50% deflection which sets the AttitudeControl gain to 50% as well.	Use the servo monitor to check if the gain channel is changing direction when actuating the "rescue switch".

When using AttitudeControl with combined switch channel make sure AttitudeControl is at least deactivated once before take off. Otherwise the tail gyro gain would be minimal as the system would not have been able to determine your tail gain adjustment after initialization.

Also note that in this mode it is absolutely necessary to use a switch that changes the control directions directly and without intermediate steps. In particular, do not use a slider on the transmitter! Otherwise, when you activate AttitudeControl the tail gyro sensitivity would be decreased to 0% before the system turns on the AttitudeControl. So you would have 0% of tail gyro gain when AttitudeControl is active.

A third alternative is to use the bank switching feature and set the attitude gains fixed for each flight mode. In this case the AttitudeControl will be active as long as the flight mode is selected and the Attitude gain is greater than 0%. So you could use one bank/flight mode for hovering and sports flying, one flight mode for 3D aerobatics and a third one with angular mode and 50% gain for rescue bailout or hover training. You can switch between modes using a simple 3-position switch.

Please note that due to the complexity of this feature configuring and enabling bank switching is only possible with the StudioX software or StudioXm app!

Functional test of AttitudeControl

When activating AttitudeControl you should be able to see an immediate impact on the swashplate control: If the heli is tilted to one side, the AR7210BX receiver permanently steers the swashplate opposed to the inclination. In the region around horizontal position the swashplate will always stay nearly horizontal to the ground (note: by default the the heli will be rolled by 4 degrees to the right, this is to compensate the tail rotor thrust when hovering!). The system constantly tries to bring the helicopter back to the horizontal position as long as the helicopter is oblique.

When AttitudeControl is deactivated on the other hand, the swashplate will always be moved back to neutral position (perpendicular to main rotor shaft) as soon as the helicopter is standing still for a few seconds, independant of the current leveling. Here the system only corrects currently occurring rotational movements, but does not regulate the absolute deviation from horizontal position.

In the modes rescue bailout and 3D - Mode the system will also control the collective pitch when it tries to rotate the heli back into level position. Here the maximum amount of pitch is determined by the setting AttitudeControl Pitch in PARAMETER MENU (Point M). When using the mode "rescue bailout with pitch" or "3D - Mode with pitch", additionally it will keep this pitch angle when level position is reached. Then the pilot only can add collective pitch in the same direction, but not in the opposite direction. Check to see if this works correctly and whether the control directions are correct. If the helicopter is kept in hovering position, some positive collective pitch must be applied by AttitudeControl and you can use the thrust stick to add more positive pitch, but not less. Analogous this must work when the heli is in inverted hovering position if using the "3D - Mode with pitch". Here AttitudeControl will apply some negative collective pitch and you can only add more negative pitch, but not positive.

Flying with AttitudeControl

If not done already, for the first flight keep AttitudeControl deactivated and adjust all flight parameters like tail gyro gain, cyclic gain and so on as described in this manual.

If the heli is set up well you can familiarize yourself with the effect of AttitudeControl. For this we suggest to use the "Bail out rescue mode". Fly the helicopter in a sufficient amount of height in a stable hover and activate the AttitudeControl by using the appropriate switch. The helicopter should continue to hover in approximately the same position. Now give some aileron or elevator stick input and release the stick when the helicopter reached some oblique position. AttitudeControl should bring the helicopter back to the horizontal position more or less rapidly.

Deactivate AttitudeControl and again tilt the helicopter by giving some stick input. Now the helicopter will stay tilted if you release the stick. Only when AttitudeControl is activated by flipping the switch again, the helicopter will be rotated back to horizontal position as before.

If using an AttitudeControl operation mode with collective pitch control, moving the thrust stick does not have any effect in some area as AttitudeControl takes over collective pitch control as long as the thrust stick is in this area and AttitudeControl is activated. Therefore make sure the thrust stick is in a position that will roughly produce the same amount of collective pitch, before and while deactivating AttitudeControl. Otherwise when deactivating AttitudeControl the helicopter would make a leap down, if the thrust stick controls a smaller pitch angle than AttitudeControl.

For safety reason you should never take off or land with activated AttitudeControl. As AttitudeControl actively gives control commands to the control loop of the AR7210BX receiver, the swashplate may tilt to one side if the helicopter is not placed perfectly level on the ground. This may cause the helicopter to tilt and crash when trying to take off or when the motor is switched off and the main rotor is running out.

Fine tuning of AttitudeControl

• The amount of deflection of the AttitudeControl switch channel controls the AttitudeControl gain. This determines the speed and roughness of the control input from AttitudeControl. If the effect of AttitudeControl is too low resp. the heli rotates back to horizontal position too slowly, increase the AttitudeControl gain by increasing the deflection of the AttitudeControl channel (i.e. by using the servo throw adjustment for this channel in the transmitter). If on the other hand the heli overshoots after reaching neutral position and bobs briefly, maybe the AttitudeControl gain is set too high. Reduce the gain accordingly. In such case also make sure that cyclic gain and cyclic feed forward are well adjusted. It is recommended to adapt the AttitudeControl gain to the preferred application. If you would like to use AttitudeControl as emergency rescue then set the gain as high as possible. On the other hand when using AttitudeControl mainly as a training aid, for example in 3D - mode, then make the effect of AttitudeControl rather weak, so that the system does take over control gently.
• In case the helicopter is not aligned horizontally as desired with active AttitudeControl, i. e. drifts to one side in hovering, the artificial horizon can be readjusted. This is done in Quicktrim Menu at PARAMETER MENU point A or by changing the trim with the StudioX software or StudioXm app. When the positioning seems to vary randomly and the tilt gets a huge offset the longer you fly, this can be due to bad position measurement. The cause for this can be high frequent vibrations, fluctuations in temperature or misalignment of the device. On the other hand please note that minor deviations are inherent. When you feel the artifical horizon gets some little offset after some time let the heli stay in hover position for a few seconds without touching the sticks. Usually the horizon will recalibrate automatically then (as long as the vibration level is not too high).
  

Adjustment at the device

If not already done enter PARAMETER MENU by pushing the button briefly when the device is operational, so that the Menu LED next to point A starts to flash. Then repeatedly press the button to skip to Menu LED (menu point) L. At PARAMETER MENU point L you can choose between five different AttitudeControl operation modes. This is done by selection with the rudder stick. Tap the rudder stick repeatedly until the Status-LED lights in the desired color. If one of the AttitudeControl operation modes is selected, the AttitudeControl function is enabled and it can be activated/deactivated in operation by using the previously assigned transmitter channel for AttitudeControl. The "AttitudeControl disabled" option specifies the AttitudeControl is completely disabled and actuating the AttitudeControl channel has no effect (in terms of the AttitudeControl). The assignment to the colors of the Status-LED is as follows:

Status-LED	AttitudeControl operation mode
off	AttitudeControl disabled
purple	Angular Mode
red flashing	Bail out rescue mode
red	Bail out rescue mode with pitch
blue flashing	3D - Mode
blue	3D - Mode with pitch

Firstly enable AttitudeControl when all initial settings in SETUP MENU and RECEIVER MENU have been performed. Otherwise the servos may drive to the mechanical full stop, start binding and may get damaged, e.g. when AttitudeControl gets activated when leaving the menu and the system starts to try moving the heli.

Briefly press the button store the setting. In case you've chosen a mode with (collective) pitch control, briefly pressing the button at point L will lead to menu point M. Otherwise menu point M will be skipped und the system will exit PARAMETER MENU.

Hovering pitch

At PARAMETER MENU point M the collective pitch will move to the set hovering position. As described above this will be used to keep the heli in hovering position (when using an AttitudeControl mode with pitch). Ideally the pitch angle is exactly as large as it is necessary to maintain a stationary hovering flight without ascending or descending. Typically this is somewhere in the range between 5 and 6 degrees.

By moving the rudder stick left or right you can descrease or increase the hovering pitch. The color of the Status-LED indicates the range where the pitch is in between at the moment. This range is specified as percentage of maximum positive/negative pitch.

Status-LED	AttitudeControl collective pitch
off	> 20% of maximum collective pitch
purple	> 30% of maximum collective pitch
red	> 50% of maximum collective pitch
blue	> 70% of maximum collective pitch

• Please note that during operation you can always add more pitch by giving thrust stick input. The pitch you adjust here is only the minimum amount of pitch. So practically in case this is not enough pitch to keep the heli in the air you will always have the option to override the pitch input for safety reason.
• When using the "3D - Mode with pitch" make sure that the maximum pitch range is symmetrical, i.e. the maximum positive and negative pitch are of same size. Otherwise the hovering pitch will differ in normal and inverted flight as the AttitudeControl pitch is calculated from each maximum pitch setting! The setting affects both directions, separate adjustment of the hovering pitch angles is not provided.
• If the maximum positive/negative pitch is changed at SETUP MENU point K in consequence also the hovering pitch will change! So after adjusting the maximum pitch also check and readjust the hovering pitch here at menu point M.
• When tilting the helicopter the amount of pitch will change and you may not see the set amount of hovering pitch. This is because the system uses an internal algorithm that controls the pitch during rotation, trying to roll the helicopter with as less horizontal and vertical movement as possible. Anyhow, this algorithm bases on the assumption that you've set the hovering pitch as good as possible. But, for examply, when you've set more pitch in order to achieve the helicopter gaining height when AttitudeControl is active, this may not cause the helicopter to turn on spot properly.

Setup with StudioX

When StudioX/StudioXm has connected to your AR7210BX receiver, in the device overview main screen click the "Parameter setup" button. Then click the "Next" button repeatedly until you reach the screen "Bank 1 - AttitudeControl" or directly go to this options screen using the box on top. Here you can choose between five different AttitudeControl operation modes. If one of the AttitudeControl operation modes is selected, the AttitudeControl function is enabled and it can be activated/deactivated in operation by using the previously assigned transmitter channel for AttitudeControl. The "AttitudeControl disabled" option specifies the AttitudeControl is completely disabled and actuating the AttitudeControl channel has no effect (in terms of the AttitudeControl).

Hovering pitch

When an AttitudeControl mode with pitch is used, you can set the minimum amount of pitch deflection that is used to keep the heli in hovering position. Ideally the pitch angle is exactly as large as it is necessary to maintain a stationary hovering flight without ascending or descending. Typically this is somewhere in the range between 5 and 6 degrees. The value you see here is the percentage of the maximum amount of pitch. So if you've set up your helicopter with 12 degrees of pitch, you will roughly see 6 degrees of hovering pitch at a value of 50. If you like to measure the exact pitch click the "Measure" button. This will move the swashplate into hovering position temporarily.

• Please note that during operation you can always add more pitch by giving thrust stick input. The pitch you adjust here is only the minimum amount of pitch. So practically in case this is not enough pitch to keep the heli in the air you will always have the option to override the pitch input for safety reason.
• When using the "3D - Mode with pitch" make sure that the maximum pitch range is symmetrical, i.e. the maximum positive and negative pitch are of same size. Otherwise the hovering pitch will differ in normal and inverted flight as the AttitudeControl pitch is calculated from each maximum pitch setting! The setting affects both directions, separate adjustment of the hovering pitch angles is not provided.
• If the maximum positive/negative pitch is changed at SETUP MENU point K in consequence also the hovering pitch will change! So after adjusting the maximum pitch also check and readjust the hovering pitch here at menu point M.
• When tilting the helicopter the amount of pitch will change and you may not see the set amount of hovering pitch. This is because the system uses an internal algorithm that controls the pitch during rotation, trying to roll the helicopter with as less horizontal and vertical movement as possible. Anyhow, this algorithm bases on the assumption that you've set the hovering pitch as good as possible. But, for examply, when you've set more pitch in order to achieve the helicopter gaining height when AttitudeControl is active, this may not cause the helicopter to turn on spot properly.

Pitch boost

The option "Pitch boost" allows to set an additional pitch input which can be added for a restricted amount of time. For example when you set the "Pitch boost" to 80 and the "Boost time" to 1000, the system will give 80% pitch input for 1 seconds (=1000 milliseconds) as soon as the helicopter reaches horizontal position when activating the AttitudeControl. So you can use this to gain height instantly and get away from the ground, i.e. when rescuing the helicopter.

• You can use the "Pitch boost" feature in any of the five AttitudeControl modes, not only in the modes with pitch! On the other hand, when using "Pitch boost" in combination with Rescue with pitch or 3D-Mode with Pitch, first the system will use the "Pitch boost" for the given amount of time and then move the pitch to the given amount of hovering pitch.
• When the "Boost time" is set to 0 the "Pitch boost" is disabled resp. will not have any effect.