PARAMETER MENU - Special parameters C to K
The points C to K of PARAMETER MENU offer a variety of settings which you may use to further improve the system performance and which allow you to adjust the flight characteristics of the helicopter to suit your personal preferences. Normally for the first flight you don‘t need to make any adjustments here.
Adjustment at the device
When the AR7210BX receiver is ready for operation, hold down the button until the Menu LED next to point A flashes quickly, then release the button immediately. The flashing menu LED A shows that you've entered menu point A of PARAMETER MENU. To skip to the setting you like to adjust, repeatedly press the button until the corresponding Menu LED flashes. The current setting of this menu point is shown by color and state of the Status LED. Tapping the rudder stick left/right you can decrease/increase the value. If you don't like to use one of the presets, you can edit each setting with the StudioX software/StudioXm app to your likings. In this case when your custom setting does not match the presets the Status LED will stay 'off. You can still choose one of the presets by tapping the rudder stick, but this will erase your custom setting.
When using the bank switching feature (only with PROEDITION firmware) you can only change the settings for bank 1 using the LED menu of the AR7210BX receiver. The parameters for banks 2 and 3 must be set in the StudioX software/StudioXm app. When disabling bank switching the settings will not change as bank 1 is used by default!
Setup with StudioX
Please note that editing parameters is only possible when the device has initialized completely. So as long as the system is not in operation mode the button to open the "Parameters" section is greyed out. If it does not pass initialization sequence check the device status shown in the middle of the screen. If the system does not finish "Receiver init" check the receiver settings and radio setup. If the system does not finish "Sensor init" make sure that it is perfectly standing still and that power supply is stable.
Click the "Parameters" button. You will find the special parameters mentioned above under "Bank 1 - Parameters". You can edit them using the given adjustment buttons. When using the bank switching feature (only with PROEDITION firmware) you can set parameters for banks 2 and 3 accordingly and switch between those different settings in flight. When bank switching is deactivated you can only set parameters for bank 1 as this is the default bank.
Speed flight stability (Point C)
When in fast forward flight apply jerky collective pitch inputs to test this parameter. The helicopter should mainly remain in its horizontal flight path during climbing and descending. If the nose of the helicopter is pitching up and down heavily like a swimming dolphin, increase the setting to compensate for this effect. But if the value is too high, the helicopter might feel sluggish and lazy. So it's best to try finding the lowest suitable setting. Note that the Cyclic Gain (usually set by Dial 1) must be set as high as possible as well. Otherwise the pitching up just may be the result of too low reaction of the gyro system in general.
If the helicopter is still pitching up at the highest value and maximum possible cyclic gain, check whether the swashplate has enough cyclic throw at high collective pitch values or use faster and stronger servos and rotor blades with very neutral phasing (for example blades specifically designed for flybarless helis).
|Status-LED||Speed flight stability|
Rudder rate consistency (Point D)
At PARAMETER MENU point D the rudder rate consistency can be adjusted. This parameter comes into play when the tail gyro is operated in HeadingLock mode. It determines how hard the tail gyro tries to maintain a given rotation rate from the transmitter. If the value is set too low, pirouettes will be inconsistent during fast forward flight or in crosswind conditions and the helicopter will slowly drift on the vertical axis when in stationary hovering flight with crosswinds. If on the other hand the setting is too high, the tail gyro will respond delayed to fast directional changes and the rudder stick control feels very inprecise. Additionally the tail might make a slow bounce after stopping from a rotational movement and commute gently while hovering or flying around. So only adjust this parameter as high as necessary.
Parameter menu point D only adjusts some part of the tail gyro control loop. First of all, you must adjust the tail gyro gain in the transmitter and use it to switch the gyro to HeadingLock mode.
- Before adjusting the rudder rate consistency always try to find the maximum amount of tail gyro gain by flying around and using the tail gyro in HeadingLock mode.
- After adjusting the rudder rate consistency it might be necessary to readjust the tail gyro gain! Both parameters interact to each other.
|Status-LED||Rudder rate consistency|
Please note that poor tail performance very often may be a sign of a stiff tail mechanics, slop in the tail linkage or an inadequate rudder servo! The tail rotor system in this case does not react as precise as necessary and hinders the tail gyro from working properly. If you cannot increase the rudder rate consistency further than “very low“ or “low“ without the tail rotor starting to slowly oscillate or bounce after doing a full stop, it is very likely that there is a mechanical issue. Also if on the other hand the tail does not turn constantly at high speeds or doesn't turn around at all, even with setting „very high“, again this may be due to a mechanical cause.
Make sure that the maximum blade pitch at the tail rotor neither is too large nor too small. A large pitch angle can lead to a stall of the tail rotor blades. Then the tail rotor produces hardly any thrust, similar to a very small angle. Also check the entire tail mechanics running smooth and without binding. Make sure that the rudder servo is strong enough and that it is supplied with sufficient power (long supply leads cause high voltage loss!). Check that the rudder servo does not get powerless at maximum servo deflection. This can happen if the pulse range of the servo is exceeded. The cause for lacking tail thrust also can be that the tail rotor blades are too small or too soft, or because the rotation speed of the tail rotor is too low!
To gain better tail gyro performance also check for correct servo horn length. If the tail gain in general is very low and the rudder tends to oscillate very easy move the linkage ball on the servo horn further inwards to the center. If on the other hand you have a very large amount of tail gain and the tail gyro still does not seem to be capable to hold the tail rotor in any flight condition, move the linkage ball on the servo horn further out from the center, to get faster response speed when the gyro needs to control the rudder.
Do not change the rudder rate consistency at menu point D in case the tail gyro does not hold well on abrupt directional changes. The rudder rate consistency doesn't compensate for sudden movements! In this case increase the gyro gain (if possible) or use the help of RevoMix feature (point F).
Stick deadzone (E)
The deadzone defines the range around the very center of the stick in which the AR7210BX receiver will not react to stick inputs. Unfortunately, some on the market available transmitters have the problem that when the sticks are brought back to the center position after a stick input, they aren’t exactly at the same center position as before. This generates a continuous deviation on the corresponding function, although the stick seems to be at mid position. This deviation is interpreted as a small input by the receiver which leads to an unwanted drift on one or more axis. Especially you can see and feel this in hovering flight when the helicopter is turning slightly to one or another direction all the time. This makes it difficult to have precise hovering as it is hard to find a stick position at which no input is sent to the AR7210BX. This can be very dangerous as it may cause the helicopter to tip over when trying to take off or it can cause the pilot to loose control over the helicopter at all! So increase the stick deadband stepwise just until you don‘t see such effects. Note that as a result of large stick deadband there will be a wide range around mid stick position in that the receiver will not react to stick inputs. This will make the control more inprecise. So if using “large“ or “very large“ deadband is necessary, we recommend to let your transmitter get checked by its manufacturer for damaged or worn out stick potentiometers.
Torque precompensation/RevoMix (F)
The advantage of always knowing the collective and cyclic inputs allows the AR7210BX receiver to help the tail gyro holding the tail in position. It can precompensate for the torque variations on the tail rotor, just before any noticeable deviation occurs. This method of torque precompensation (RevoMix) relieves the tail control loop and improves the tail performance, especially when using the AR7210BX on helicopters with insufficient tail authority and/or extreme motor torque (e.g. overpowered electric helicopters) where the tail does blow out for a short moment when applying a sudden collective or cyclic input.
In general you can see the compensation when you move the collective or cyclic control sticks. With precompensation activated the tail rotor has to produce a deflection which must counteract the rotor torque. Since at 0° pitch the least torque is applied by the main rotor, also the tail rotor makes the least deflection and the tail slider is in center position. If you pitch in positive or negative direction or move aileron or elevator control, a deflection will be added to the tail rotor which will act against the torque of the main rotor. For helicopters with clockwise rotating main rotor, the precompensation has to always push the tail to the left (nose of the heli to the right). For helicopters with the main rotor turning anti-clockwise, the precompensation has to push the tail to the right (nose of the heli to the left). The deflection will be to the same direction, whether positive or negative pitch, as the torque only increases. So when doing the adjustment first of all check which direction is needed for your helicopter. Then choose the amount of precompensation from the given preset or adjust freely using the StudioX Software/StudioXm App.
When doing the adjustment on the device the rudder servo will directly move into the direction of compensation. So you can easily see, where the tail will move when adding pitch. When precompensation is set to "high" the servo will move further than with "low", so you get an additional visual reference of what you're adjusting at the moment.
|red flashing||low - normal direction|
|red||high - normal direction|
|blue flashing||low - reverse direction|
|blue||high - reverse direction|
Use torque precompensation when the tail does go away in torque direction when applying a sudden pitch input, even if the tail gyro gain is properly setup. Increase the amount of precompensation stepwise until the tail holds well. If the tail is moving against torque direction, the amount of precompensation is too high already. If the tail is blowing out even worse when torque precompensation is active, probably the direction of torque precompensation is wrong! If you can't find a good adjustment check the mechanical conditions. Use different (larger) tail rotor blades or higher tail rotor speed to gain better holding force. Also check your tail gyro gain. If the tail gyro gain is very low in general and the rudder tends to oscillate very easily move the linkage ball on the servo horn further inwards to the center. If on the other hand you have a very large amount of tail gain and the tail gyro still does not seem to be capable to hold the tail rotor in any flight condition, move the linkage ball on the servo horn further out from the center, to get faster response speed when the gyro needs to control the rudder.
Torque precompensation can only be used when you have 0° of pitch at SETUP MENU point H (servo trim)!
Cyclic response (G)
With point G can be set how aggressive the AR7210BX receiver responds to cyclic control commands (roll and pitch). This can reduce the usual uniform and linear control feeling of flybarless systems and approach it to the feeling of a flybared helicopter.
If you want to use this feature, start from the "slightly increased" setting, gradually increasing to the desired level, until you have found your ideal setting. A too high setting will result in uncontrollable, inaccurate rotation and deteriorating stopping behavior of each control function. How high this feature is adjustable without causing any adverse effects depends on many factors such as heli size, swashplate servos, main rotor blades, main rotor speed, servo power supply and depending on the particular heli setup.
|red flashing||slightly increased|
Pitch boost (H)
PARAMETER MENU point H allows you to setup the collective pitch boost function. This function causes that the faster you move the thrust stick, the more additional collective pitch will be exposed. This can be especially useful in 3D aerobatics when very rapid collective pitch changes are necessary for certain flight maneuvers, as hereby dynamically the required control stick deflection will be reduced. However, the maximum pitch value will not be exceeded.
When the setting is too high, this can cause the rotor blades to stall when giving very fast collective pitch commands. The collective pitch will feel slow and spongy, precisely causing the opposite effect as desired. Also note that a high setting can make the pitch control inprecise and more sensitive, as when giving fast stick input, the pitch will overshoot.
Start from the "low" setting, gradually increasing to the desired level, until you have found your ideal setting. How high this feature is adjustable without causing any adverse effects depends on many factors, such as maximum pitch values, pitch curve, swashplate servos, main rotor blades, system headspeed, pilot skills, ... .
Throttle response (I)
Use PARAMETER MENU point I to change the response of the internal Governor control. This determines how fast and how far the system will open the throttle when the rotor speed changes. Ideally the response is set as high as possible. If it is too low, the main rotor will speed up in unloaded conditions as the system reduces throttle not quick enough. Also the internal Governor will increase throttle very cautious when the rotor is loaded, so that the head speed will drop. If on the other hand the response is set too high, the throttle may stutter audible and the throttle will kick in very hard. So the motor speed will overshoot when the rotor head is loaded. This will make the headspeed even more inconsistent than with a lower setting. The height of throttle response highly depends on factors such as heli size (blade size), motor power and performance and/or the throttle reponse behavior of the speed controller (when flying an electric heli). If you need to adjust the throttle response, we recommend to start with the lowest value and increase stepwise just until you get the most consistent rotor head speed. Having a heli with good motor power and a fast responding speed controller (on electric helis) typically allows to have high throttle response values (up to "very aggressive" setting) which will give very consistent head speed. Helis with not so much power (small nitros, gasser, scale helis) prefer low throttle response settings for a softer throttle management.
|red flashing||slightly increased|
Slow rampup speed (J)
When using the internal Governor function this will not apply full throttle immediately when switching into idle up but will increase the motor speed slowly until the desired head speed is reached. At menu point J you can determine how fast this soft start occurs when the Governor is activated initially. The speed is given in number of revolutions by how much the rotor speed is increased per second. The higher the speed the faster your preset head speed will be reached. Please note that the given rates only are indicative. Depending on the response of the speed controller and the inertia of the rotor system it can actually take longer or shorter until the desired speed is reached.
|Status-LED||Slow rampup speed|
|red flashing||100 rps|
|blue flashing||300 rps|
With the StudioX software/StudioXm App you have the option to disable the softstart feature, which will set the spool up rate to "0". This is necessary when using a speed controler with built-in softstart feature (but without headspeed governing!). In this case the system will add half throttle immediately and wait until the speed controler has finished the spool up. Then it will activate the governing.
Please note that you can't set a speed lower than 50 rps with StudioX because of the fact noted above. Setting the speed below 50 will be the same as setting it to 0, so it will disable the soft start!
Fast rampup speed (K)
When using the internal governor function and you change the head speed in the transmitter in flight (i.e. by switching to a different flight mode), there will not be an abrupt change but the system will increase the rotor rpm with a given rate that can be adjusted here. This rate also determines how fast the rotor head speed will increase when reactivating the Governor after an autorotation maneuver (Autorotation bailout). In this case, when the heli is still in the air, the normal soft start (which is set at point J) would take way too much time for the rotor to speed up again, so we use this faster spool up rate instead.
|Status-LED||Fast rampup speed|
|purple||same as slow rampup speed (J)|
|red flashing||300 rps|
|blue flashing||700 rps|
When using a very fast rampup speed in consequence the throttle will be opened very quick. Especially when recovering from an autorotation maneuver this can cause the rotor blades to fold in or will damage the main gear. So only increase the value stepwise and with care. With nitro helicopters using quite low values is recommended (even the setting "same as slow rampup speed (J)" may be sufficient) as here an abrupt throttle change from idle position can cause the engine to quit! Also nitro motors react quite slow to throttle changes and it takes some time to speed up the rotor. When the change rate does not fit to the physical speed up, it can happen that the motor is driven to full throttle during spool up by accident as the motor does not come to speed. In this case for technical reason it may happen that the systems stays at full throttle then!