Eagle Tree Systems Guardian 2D/3D Stabilizer Manuel utilisateur

Table of Contents

Introduction 1

Specifications 1

How to Get Help 1

Terms and Symbols used in the Manual 1

Main Features 2

Overview/Quick Start 2

Guardian Physical Connections/ Controls 3

The Receiver Connection Harness 4

Receiver Requirements 4

Mounting the Guardian in your Model 5

Preflight Checks 6

First Flight 6

Tuning Stabilization Gains 6

Status LED 8

Mode/Config Switch Behavior 8

The Guardian PC Software 10

Guardian Configuration Page Software

Reference 11

Troubleshooting / F.A.Q. 12

Limited Warranty

Guardian 2D/3D Stabilizer

Document Version 2.0

Assembled in Taiwan

Introduction

Thank you for your purchase! Based on Eagle Tree's proven inertial stabilization technology, the Guardian 2D/3D Stabilizer (the Guardian) stabilizes just about any type of

fixed wing model, and works with any radio. Unlike most “gyro stabilizer” products on the market, the Guardian provides true wing leveling stabilization as well as precise

fly-by-wire control. This lets you configure the Guardian to return to level flight in an emergency, by just flipping a radio switch!

This instruction manual will guide you through the installation and operation of your Guardian. The latest version of this manual is available in the Product Manuals

section of the Support tab on http://www.eagletreesystems.com. The online manual is in full color, and includes any updates that were made after this manual was

produced. Please read the entire manual carefully before proceeding. If, after you read the manual, you have further questions or problems, see the “How to Get

Help” section below.

Packing List

Your package should include the following: The Guardian, the receiver connection harness with labeled

connectors, the quick reference card, and a printed version of this manual.

Specifications (approximate)

•Input Voltage Range: 4.5v to 16v

•Current Draw: Approximately 31mA

•Dimensions: 41mm x 22mm x 11mm (1.62 inches x 0.86 inches x 0.42 inches)

•Mass: 11 grams (0.4 ounces) including harness

•Maximum Servo Current through Guardian: 5 Amps

How to Get Help

Eagle Tree is committed to providing great customer service. If you’ve read the manual and something is not clear,

just ask. We’d much prefer to take the time to answer your questions, rather than having you waste your valuable

time struggling with an issue.

To get help, visit the Eagle Tree Guardian support thread at

http://www.rcgroups.com/forums/showthread.php?t=1596644. Chances are someone has posted a solution to your

problem already. If not, posting your problem there will get a very quick response from the Eagle Tree community.

If you prefer to not post on the forum, or you feel there is a problem with your Eagle Tree hardware, please open a

support ticket with us at http://ticket.eagletreesystems.com and we will respond to your support ticket as soon as we

can. Note that when you create a support ticket, you will be emailed a link that will let you check the status of the

ticket. If you do not receive the email, this most likely means that a spam filter is intercepting emails from Eagle

Tree.

Also Eagle Tree greatly values your feedback on how we can improve our products. To leave us feedback for a

new feature request or improvement, either post the feedback on our support thread above, create a support ticket

with your feedback, or send feedback at http://www.eagletreesystems.com/Feature/feature.html

Terms and Symbols used in the Manual

Warning or Caution

Helpful Note

Pitch – Lift or descent of the nose and tail of the model. Normally controlled by the elevator, or

movement of elevons in same direction.

Roll – Rocking movement of the wings, side to side. Normally controlled by ailerons, or

movement of elevons in opposite directions.

Yaw – Turning of the airplane without banking. Normally controlled by the rudder.

Axis – an imaginary line drawn horizontally through your model’s wing (for Pitch), horizontally

through your fuselage (for roll), or vertically through the center of your fuselage (for yaw).

Control Stick – The stick on your radio that controls elevator and aileron functions (pitch and roll).

Attitude – The orientation of the model with respect to the horizon.

2D Mode – A mode where the model is brought to a level attitude (level flight and level wings) by

the Guardian when the control stick is centered.

3D Mode – A mode where the Guardian attempts to hold the model’s present attitude when the

Control Stick is centered, by moving the model’s control surfaces automatically.

Heading – The present direction of travel of the model with respect to North.

Control Surfaces – Your model’s elevator, ailerons (or elevons) and rudder (if equipped).

Receiver Connection Harness – The cable included with your Guardian that lets you connect your Guardian to your receiver’s outputs.

Mode/Config Switch – A two or three position switch on your radio transmitter which you have configured to control the “Mod” input on the Guardian’s Receiver

Connection Harness.

Toggle – One fairly rapid movement the Mode/Config Switch between its extents. (UP/DOWN or DOWN/UP)

Configuration Gestures – A series of toggles of the Mode Config/Switch. The number of times you toggle the switch determines which configuration step is performed.

Gain Knob – A knob or switch on your radio transmitter which you have configured to control the “Gain” input on the Guardian’s Receiver Connection Harness.

General Safety Precautions

In addition to other warnings and other precautions in this manual, the following should always be observed:

1) The Guardian is intended for recreational use only! Any other use is not supported.

2) Fly safely! Please refer to the American Model Association’s Safety Code at http://www.modelaircraft.org/files/105.PDF, or the appropriate safety code for

your country. Always obey the law when flying.

3) If you have never set up or operated an RC model before, you will need help from an experienced modeler. Local RC clubs are great ways to meet experienced

modelers, and receive the required training.

4) Never operate your model aircraft near or over buildings, power/telephone lines, or other obstacles. Never operate your model aircraft near or over other people!

5) RC models and accessories are not toys, and should be kept away from children, without proper adult supervision.

6) Be sure to always fly conservatively and exercise common sense, especially while learning to use the Guardian.

Main Features

The Guardian 2D/3D Stabilizer has two main modes of operation: 2D Mode and 3D Mode. While in flight, a spare switch on your radio lets you switch between 2D mode,

3D aerobatic mode, and no stabilization. Imagine performing a difficult 3D maneuver with ease, then just flipping a switch to instantly return to level flight!

Please see the Tuning Stabilization Gains section for notes on preventing damage from re-leveling too quickly.

2D Mode

When set for 2D Mode, the Guardian provides much smoother flight and wing leveling stabilization for your model, which makes it a lot easier to adjust and fly your plane.

In this mode, the Guardian "remembers" level flight for your model and returns it to level flight when needed. In 2D mode, flying in moderate wind can seem just as easy

as flying in no wind at all!

Additionally, the Guardian provides precise "fly by wire" control, in which it interprets your control stick deflections as command angles for Pitch and Roll. For example,

pushing and holding your control stick left will cause your model to enter a level altitude banked left turn. This mode is ideal for beginners as well as experts looking for a

reduced workload on take-off and landing. It also can be useful for aerobatic pilots seeking to recover quickly after losing orientation.

The Guardian also includes an advanced “Oscillation Suppression” feature that can quickly detect and eliminate oscillations stemming from too high gains.

2D Heading Hold Submode

With 2D Heading Hold submode, the Guardian will assert Aileron deflections to keep your model locked on its current 2D heading. Whenever the control stick is moved to

turn, this heading is reset and subsequently relocked as soon as the stick is centered again.

Automatic Turn Coordination

When enabled, Automatic Turn Coordination will cause the Guardian to employ the “step on the ball” method of actuating your Rudder for you. As you enter a banked

turn, the Guardian will assert a coordinating response on the Rudder automatically. This deflection is completely based on the side-to-side g-force measured by the

Guardian and does not introduce any movement on the Ailerons. This mode is great for models that skid easily.

Expected behavior here is that on the bench, the Guardian will introduce a Rudder movement that will yaw the model towards the direction it is being rolled. For

instance, if a stationary plane is rolled to the right, the Rudder should assert a right yaw moment to follow the detected turn.

Since this is based on horizontal g-force, the Guardian may exhibit different behavior in the air in a “skid” condition where the model is moving one direction, but

pointing another. The Automatic Turn Coordination will work to point the model in the direction that it is moving through the air in this case.

3D Mode

In 3D Mode, the Guardian works to smooth out turbulence and stall characteristics to bring stability and precision to your model while leaving the feel of flying the same as

without stabilization. This mode is intended for more advanced pilots looking for improved stability without compromising on performance and feel.

3D Heading Hold Submode

Centering the control stick in 3D Mode will engage 3D Heading Lock, which will cause your airplane to hold its present flight orientation (assuming it is aerodynamically

able to do so). In this mode, when the control stick is centered the Guardian remembers its current Pitch, Roll and Heading and works to keep those locked. Moving the

control stick immediately resets the locked heading, allowing for instantaneous transitions from locked maneuvers to dynamic flight. Actuation of the Rudder control will

reset just the Yaw axis, without affecting the lock on Pitch and Roll.

Direct Rate 3D Control Submode

Unlike many other gyro stabilization systems, the Guardian employs Direct Rate 3D Control to translate your stick deflections to angular rates without forcing you to “fight

the gyro.” With this feature enabled, the Guardian interprets your stick deflections as commanded angular rates and attempts to have your model follow those commands.

This way, snap rolls and other high speed maneuvers are possible without compromising on stabilization effects.

Overview/Quick Start

First, read through the manual to get a “big picture” understanding of mounting, connection, configuration and operation of the Guardian.

Consider watching the Guardian tutorial video located at http://youtu.be/Rt8Y3Lxnv-0.

While the Guardian has a wealth of configurable features and options, getting in the air for most airframes requires minimal setup and configuration. At a minimum, the

Guardian should be connected between your receiver and your servos and then told some basic orientation and trim details of your model. These steps are detailed as

follows. Note: it is assumed here that you have a transmitter switch connected to the Guardian’s Mode/Config input.

•Connect the Guardian to your receiver using the included servo wire harness. Refer to the Receiver Connection Harness section for more information.

•Connect your servos to the matching servo output channels on the Guardian. Note that the servo connectors’ signal wires should be on top when the Guardian’s

label is facing the sky. See the Wing Type Configuration section for details on specific airframes.

Figure 1 – Guardian Connections and Controls

•To reduce the possibility of extreme servo deflection, it is recommended that you disable stabilization during initial setup. There are 3 ways to disable

stabilization:

oIf you are using a 3 position Mode/Config switch, move it to the center (disabled) position.

The Guardian’s LED should be OFF when in the Mode/Config switch is in the disabled position.

oIf you are controlling overall Guardian gain with a knob on your transmitter, set your Gain dial to -100% servo deflection (~1.1ms pulse length) to disable

stabilization.

oIf neither of these methods is applicable, turn the Pitch/Roll/Yaw dials on the Guardian to their centered position, which will also disable stabilization.

•Configure your Guardian and transmitter for your wing type (see the Wing Type Configuration section for more information):

oTurn off Elevon and V-Tail mixing in your transmitter, if it is enabled. Elevon and V-Tail mixing will be done by the Guardian.

oBy default, the Guardian is programmed for traditional wing types (mixing disabled). If your model requires elevon or V-Tail mixing, you can quickly

enable this feature by doing the following:

Within 15 seconds of powering on, toggle your Mode/Config switch three times, which is the Toggle Elevon Mixing switch gesture (move the

switch up-down-up-down-up-down if the switch is presently down, or down-up-down-up-down-up if the switch is presently up).

Your servos should “twitch” three times to indicate that you have toggled elevon mixing ON/OFF.

Move your control sticks to ensure that the mixing is now enabled. If not, you may need to re-run the Enable Elevon Mixing step.

Configuring the wing type correctly is critical! The model will not be controllable in the air if the wing type is incorrect.

•Place your plane on a test bench so its orientation is the same as it would be during straight and level flight.

•Reset your Trims and Level Flight Orientation:

oWithin 15 seconds of powering on, and with your plane still in the orientation of level flight, toggle your Mode/Config switch once, which is the Reset

Level Flight and Trims switch gesture. Your servos should “twitch” once to indicate that you have reset your controller trims and level flight orientation.

Any time you re-trim your plane or re-mount the Guardian, you will need to do this again to ensure best stabilization performance.

•Compensate for servo directions and throws:

oSet your Mode/Config switch to -100% (switch position 2 on a Spektrum

controller). This activates “2D Mode”.

The Guardian’s LED should be blinking on and off repeatedly, which indicates 2D Mode.

oTurn up the Overall Gain knob on your transmitter its center position (100% overall stabilization gain) if you are using the gain knob.

oObserve how your servos react as you pitch, roll and yaw your plane.

oAdjust the Guardian Pitch, Roll and Yaw axis dials with a screwdriver, so the servo for each axis deflects in the correct direction to bring your model back

to level. A centered dial asserts zero stabilization on that axis. Turning it clockwise or counterclockwise increases the gain and selects the servo

stabilization direction. See Figure 6 to see which directions your surfaces should move as you move your model.

•Ensure your Transmitter’s elevator and aileron endpoints are set for +/-100%, if applicable.

The Guardian expects full ranges when it interprets your command

stick deflections to determine the desired orientation in 2D Mode.

•Preflight:

oCheck that when you pitch, roll and yaw your plane while in either 2D or 3D Mode, that your servos oppose your movements. See Figure 6 in the

Preflight Checks section for more information.

If the control surfaces are not correctly set up to move in the appropriate directions to counteract pitch, roll and yaw movements, it could result

in a crash!

oDo an engine run-up and confirm that the control surfaces are not moving around randomly due to excessive vibration or a loosely mounted Guardian.

If the control surfaces are moving on their own during run-up, this could result in a crash! Do not fly if this is the case.

oRange check your model!

Guardian Physical Connections/ Controls

Please refer to Figure 1. The Guardian has the following physical connections and controls:

•Port for Receiver Connection Harness – this is where the included harness connects. The servo plugs on the harness then connect to the appropriate receiver channels.

Please see the Receiver Connection Harness section below for more

information.

•Servo Connection Ports – connect the appropriate servos to the

Guardian here, noting the plug orientation in Figure 1. Please see the

Wing Hookup Configurations section below for more information.

•Yaw, Roll and Pitch gain control dials – these dials set the individual

gains for the Yaw (Rudder), Roll (Aileron) and Pitch (Elevator) axes, as

well as setting the direction of stabilizing servo travel, and are adjusted

with a small screwdriver. Please see the Tuning Stabilization Gains

section for more information.

•Micro USB port – this port accepts a “Micro B” USB cable (not

included). Connection to a PC lets you update the Guardian firmware,

and also configure and tune your Guardian via your PC. Please see the

PC User Interface section for more information.

Do not apply upward force on the USB connector when a

cable is inserted! Doing so can damage it.

•Accessory (Data) Port – this port is for future expansion, and is not used

presently. Please let us know how we should use this port!

•LED Viewports – for your convenience, the status LED can be seen from both the top and side of the Guardian case. Please see the Status LED section for more

information.

Figure 2 – Receiver Connection Harness

Figure 3 – Providing Backup Power when all Guardian Servo Channels Used

The Receiver Connection Harness

Receiver Connection Harness Pinout

The lightweight receiver connection harness with labeled connectors should make it easy for you to hook

up the Guardian to your receiver.

A diagram of the harness is shown in Figure 2, for your reference. It has the following labeled receiver

connections:

•Ail – (required) Connects to your receiver’s Aileron output channel. Note that this channel also

supplies power and ground to the Guardian and the servos connected to the Guardian.

•Elv – (required) Connects to your receiver’s Elevator output channel

•Rud – (optional) Connects to your receiver’s Rudder output channel

•Aux - (optional) Connects to your receiver’s Second Aileron or Flaperon output channel, if needed

•Mod – (optional, recommended) The Mode/Config input connects to either a two-position or three-

position switch. It allows you to switch the Guardian mode during flight and to do radio stick

configuration of the Guardian. See the Mode/Config Switch Behavior section for more information.

•Gain – (optional) The Gain input connects to a knob (or slider) on your receiver, and lets you adjust

the overall stabilizer gain during flight. See the Stabilization “Master Gain” Control section for more

information.

Receiver Connection Harness Load Capacity

When connected typically, the Aileron lead of the Guardian’s receiver connection harness takes power from

your receiver, and this powers the servos you have connected to the Guardian. The Receiver Connection

Harness is easily capable of handling the power requirements of typical analog and digital servos.

However, if the servos you have connected to the Guardian are very large, and/or have a combined current draw of greater than 5 amps, an additional

power cable is required. Note that if your BEC or receiver battery is rated at 5 amps or less (the vast majority are), a backup cable should not be needed. Note

also that the Aileron lead of the harness should not be excessively warm after flying, which could indicate that backup power is needed.

If the servos you have connected to the Guardian draw greater than

5 amps all together, there are two ways to supply additional power

to your servos, which will provide additional current carrying

capability to the servos you have connected to the Guardian:

1) If you are not using all the servo output connections on your

Guardian, a male to male servo wire (with the signal line cut!)

can be connected between a free servo channel on the

Guardian, and a free channel on your receiver.

2) If all the servo connections on the Guardian are being used, a

male/male/female Y cable (ET p/n CAB-Y-1 or similar) with

the signal line cut can be used to provide additional power to

the servos, as shown in Figure 3.

Receiver Requirements

Receiver Connection Requirements

The number of connections between the Guardian and your receiver depends on type and capabilities of your model, the level of Guardian in-flight control you require, and

the number of spare receiver channels you have. For very basic models, the Guardian is capable of operating with only the Elevator input and Aileron input connected.

BEC/Receiver Battery Power Requirements

The Guardian 2D/3D Stabilizer is sensitive to deep voltage drops, which means that your BEC or receiver battery must be sufficient to maintain a voltage of at least

3.5 volts, even under full servo load. The Guardian will shut off if the voltage drops below this level! Under normal conditions, the BEC voltage should

be at least 4.5 volts to achieve the best stabilization performance. Never exceed 16V!

If the voltage drops below 3.5 volts for a short period of time, the Guardian will experience a “brownout.” In this case, the Guardian will attempt to recover gracefully.

During recovery, stabilization may be disabled or suffer from performance issues while it does so.

If you experience issues like this in flight, bring the Mode/Config Switch to either 3D Mode or Stabilization Disabled Mode (if your transmitter is

configured for mode control) and land immediately.

If a brownout condition is detected by the Guardian, the LED will blink an error code of four long blinks followed by one short blink. If this LED signal is ever seen after a

flight, it is recommended that the BEC or battery be upgraded. Please see the Status LED section for more information on how to interpret LED blinks.

Failsafe position of Receiver Inputs

If, after you reset level flight and trims, an input channel should become disconnected from your receiver during flight, it will cause the Guardian to use the stored

trim setting for that servo channel input as a failsafe.

Functionality Limitations without the Mode and Gain Inputs or the PC Connection

While the Guardian is capable of flying without the Mode or Gain inputs being connected, most configuration steps need either the Mode input or a PC connection

in order to be done correctly. The Guardian comes preconfigured for standard fixed wing flight. Configuring the Guardian any other way will need to be set up

using either the Radio Stick Menu, which is activated using the Mode switch, or the PC Software, which requires a USB connection. Either the Mode Input or a PC is

needed to Reset Level Flight and Trims as well.

In the case where neither of these is available, it is recommended that you remap an unused channel, such as Throttle or Rudder to the Mode Input temporarily to emulate a

Mode Switch. Next, ensuring that your controller’s servo ranges for that channel are set to 100%, the remapped channel can be used to enter the Radio Stick Menu.

While the Radio Stick Menu will allow most configurations, it is only possible to access some features through the PC Software. These include the AHI display, saving and

reloading past configurations and the ability to limit your Servo Deflections (available under the Servo Config tab).

Traditional Models with Single Aileron Servo

•Model Control Type setting: Standard (this is the default)

•Guardian Receiver Inputs

oReceiver Aileron Output →Guardian Aileron In

oReceiver Elevator Output →Guardian Elevator In

oReceiver Rudder Output →Guardian Rudder In

oGuardian Aux-In is not connected

•Guardian Servo Outputs

oGuardian Aileron Out →Aileron Servo (if no Aileron

present, connect Rudder Servo to Aileron Out)

oGuardian Elevator Out →Elevator Servo

oGuardian Rudder Out →Rudder Servo

oGuardian Aux Out is not connected

Traditional Models with Dual Aileron/ Flaperon servos (with

Transmitter mixing)

•Model Control Type setting: Standard (this is the default)

•Guardian Receiver Inputs

oReceiver Aileron Output →Guardian Aileron In

oReceiver Elevator Output →Guardian Elevator In

oReceiver Rudder Output →Guardian Rudder In

oReceiver Second Aileron or Flaperon Output →Guardian

Aux In

•Guardian Servo Outputs

oGuardian Aileron Out →Aileron Servo

oGuardian Elevator Out →Elevator Servo

oGuardian Rudder Out →Rudder Servo

oGuardian Aux Out →Second Aileron or Flaperon Servo

V-Tail with Ailerons

•Model Control Type setting: V-Tail

•Guardian Receiver Inputs

oReceiver Aileron Output →Guardian Aileron In

oReceiver Elevator Output →Guardian Elevator In

oReceiver Rudder Output →Guardian Rudder In

oReceiver Second Aileron Output →Guardian Aux In

(optional)

•Output

oGuardian Aileron Out →Aileron Servo

oGuardian Elevator Out →V-Tail Servo 1

oGuardian Rudder Out →V-Tail Servo 2

oGuardian Aux Out →Second Aileron Servo (optional)

Elevon / V-Tail with no Ailerons

•Model Control Type setting: Elevon

•Guardian Receiver Inputs

oReceiver Aileron Output →Guardian Aileron In

oReceiver Elevator Output →Guardian Elevator In

oReceiver Rudder Output →Guardian Rudder In

oGuardian Aux-In is not connected

•Output

oGuardian Aileron Out →Elevon Servo 1

oGuardian Elevator Out →Elevon Servo 2

oGuardian Rudder Out →Rudder Servo

oGuardian Aux Out is not connected

Figure 4: Receiver and Servo Connections for Typical Wing Types

Figure 5 – Good and Bad Ways to Mount the Guardian

Wing Type Configuration

The Guardian is configurable for most common wing types. By default, it is configured for traditional wing control. Please refer to Figure 4, which shows the receiver and

servo connections for typical wing types.

The Guardian requires unmixed control inputs from your receiver, even if you have a V-Tail or Elevon model. If you have a V-Tail or Elevon model, the

Guardian does the mixing internally, so you will need to change your transmitter configuration to standard wing type, rather than having your transmitter do the mixing.

For airframe types other than standard and dual Aileron/Flaperon, you will need to be change the “Model Control Type” setting, using either the radio stick

configuration or the PC software. See the Menu Operation section below for more information on changing this setting.

Dual Ailerons/Flaperons

An exception to the unmixed input requirement is made for Dual Aileron and Flaperon models. By default, the Guardian will accept premixed Dual Aileron or Flaperon

inputs to its Aileron and Aux inputs. But, if your controller does not have the capability of performing Dual Aileron or Flaperon mixing, then the Guardian can be

configured to do this for you. See the List of Features and Options: Onboard Dual Aileron Mixing Enabled menu option for more information.

Mounting the Guardian in your Model

Please refer to Figure 5, which indicates correct and wrong Guardian mounting.

Make sure you are mounting the

Guardian in one of the correct ways

shown below! The Guardian will not work

correctly otherwise!

Mount the Guardian securely with two sided

servo tape, Velcro, or similar, so that it is in line

with your direction of flight. It should be

mounted near the model’s center of gravity and

level to the horizon when your plane is flying

straight and level, but the Guardian will

compensate for small mounting errors.

Choose a mounting location which will allow the

Guardian to be easily connected to your receiver

and servos.

If the Guardian comes loose from its

mounting location during flight, it will

not be able to correctly stabilize your model!

After mounting, be sure to pull up on the

Guardian with a force greater than you expect

to encounter in flight, to confirm mounting

integrity.

Figure 6 – Correct and Incorrect Control Surface Movement

If permanently mounting the Guardian, ensure that the USB port is still accessible for PC configuration and firmware update.

Preflight Checks

Before every flight, it is strongly recommended that you

perform the following steps:

•Perform your normal preflight check. Ensure your

servos respond correctly to your RC control stick

commands.

•To test that the Guardian is working, hold the

airplane level. Now, pitch, roll and yaw the

model. Please see Figure 6. You should see the

control surfaces deflecting appropriately to level

the airplane and keep it on a straight heading. If

the control surfaces do not move at all, ensure that

the Master Gain knob on your transmitter (if used)

is set so that stabilization will occur, and ensure

that the Mode/Config switch (if used) is set for

either 2D or 3D Mode.

If any of your control surfaces are moving the

wrong direction, you need to reverse the

direction of the appropriate Guardian Gain Control

Dial!

First Flight

To account for trims and mounting errors of the

Guardian within your plane, follow the instructions in

the section titled “Reset Level Flight and Trims.”

On your first flight, it is recommended that you do an

unpowered hand-toss of your airplane, if it is capable of

hand-toss launches. If the airplane safely glides to the

ground with little or no input, then your configuration is

correct. If the model oscillates or overcompensates

during the hand-toss, your Gain is too high.

Once it has been shown that the Guardian has been correctly configured, perform a run-up on the ground with stabilization enabled, while watching your control surfaces for

drift. If it appears as if stabilization is working properly with the engine active, then throttle down, perform one last preflight check and take off with power.

Don’t fly your model if your control surfaces are moving unexpectedly during engine run-up!

Once in the air and only when safe, release the control stick so it sits at zero deflection with 2D Mode enabled. Your airplane should fly straight and level. If not, your

Guardian may be mounted improperly or you need to re-trim your airframe. Disable stabilization by flipping the Mode/Config switch to the center position (if available).

Trim your controller in this mode until the plane achieves level flight. Land and follow the instructions for “Resetting Trims” on the ground.

Tuning Stabilization Gains

Stabilization Theory

The Guardian 2D/3D Stabilizer uses accelerometers and gyroscopes to measure the orientation of your model relative to the local direction of Earth’s gravity. In addition, it

interprets Pitch and Roll attitudes commanded by your Elevator and Aileron stick movements, respectively.

With this information, it is able to determine the error between your requested flight attitude and your plane’s true orientation. By passing this error through a controller

algorithm and sending it as servo commands through its Elevator, Aileron and Rudder outputs, the Guardian can help turn your squirrely model into a smooth-flying wing

on rails!

Each axis has a separate gain control dial, which is used to adjust gain on that axis. The Pitch, Roll and Yaw gains are then scaled by the optional Overall “Master Gain”

control, which can be mapped to a knob (or slider) on your transmitter. This arrangement allows individual axis gain adjustment while also providing in-flight Overall Gain

adjustment to compensate for varying conditions and aerodynamic performance.

In general, the higher the gain, the more responsive and resilient your plane will be to disturbances such as wind, balance and trim issues. Tuning the gains too high

however may result in oscillations of the airframe. It is recommended that the Master Gain control be used to tune the airframe until it barely oscillates and then be turned

back down. This will ensure the best performance while preventing future oscillations.

Components of Stabilization

The Guardian employs two major techniques to stabilize your model: “rate stabilization and “orientation stabilization”. Sometimes called “derivative” and “proportional”

stabilization respectively, these two behaviors work together to smooth out bumps in the air while keeping your model in the orientation you want it.

Rate Stabilization

This is the reaction of the model to instantaneous motion. Specifically, it is the movement of your servos to oppose the angular rate of your model. The faster your model

is rotating in a given direction, the harder the Guardian will oppose that motion. This is the effect that smoothes turbulence and makes your model feel more stable. In

addition, when you fly in 3D Mode with 3D Heading Hold disabled, this is the only type of stabilization used.

Orientation Stabilization

This is the reaction of the model to the error between its current orientation and its commanded orientation. For instance, in 2D Mode with the sticks centered, the further

the model is brought from level orientation, the harder the Guardian will fight to bring it back. This behavior is also used in 3D Mode when 3D Heading Hold is active to

keep the model pointed in its locked direction.

Figure 7 – Guardian Gain Control Dials

Figure 7A - Guardian Master Gain Control

When in 3D Mode, Orientation Stabilization is used in the Pitch, Roll and Yaw axes to keep your model on track. When in 2D Mode, Orientation Stabilization is

only used on the Pitch and Roll axes, leaving the Yaw axis (Rudder) only with Rate Stabilization. This will make the Rudder appear to be stabilizing less than the Elevator

and Ailerons (or Elevons) in 2D Mode. This is expected behavior.

Individual Axis Gain Dials

The gain control dials on the Guardian can be used for tuning the individual axes on your airframe. In addition,

they allow for the reversal of the direction of stabilization servo travel. When a dial is centered (with the

“double-dot” dial indication facing upwards, as shown in Figure 7) the gain for that axis is set to zero. This

effectively disables stabilization on that axis.

When a dial is rotated away from its centered position in the clockwise direction, the gain for that axis is

increased, and the stabilization deflection direction is set to normal. If the dial is rotated counterclockwise from

its centered position, the gain will be increased as well, but the stabilization deflection direction will be reversed.

This allows for stabilization to be tuned for any airframe, regardless of servo orientations.

If you have difficulty seeing the double-dot indication on the dials, you can either gently rotate the dials

counterclockwise and clockwise to find the approximate center point, or you can use the PC software to visualize the dial settings on your computer screen.

Stabilization “Master Gain” Control

The Master Gain control increases or decreases the effective amplitude of the Pitch/Roll/Yaw gain dials and serves as a way to easily tune all

three. If you have an RC controller that has a free analog knob or slider, this can be mapped to the Gain channel to allow for overall in-flight

stabilization gain adjustment. The higher the gain knob setting, the stronger the Guardian’s stabilization effect will be.

Another way to think about this is that it is similar to a graphic equalizer and volume control on a stereo. The individual gains are similar to the

sliders on the equalizer, while the Master Gain is similar to the overall volume control.

Though not required, ideally the Gain wire from the Guardian will be plugged into a channel controlled by a knob, slider or switch on the

transmitter. If you do not have a knob or slider on your transmitter than can be used for the Master Gain function, you may use a two or three

position switch to provide low/high or low/mid/high gains by adjusting the travel limits in your transmitter. If you have no available channel for the Gain wire, you may

leave it disconnected. In this case, the gain range of the individual gain dials is reduced to slightly

less than half of the maximum possible gain to reduce the possibility of encountering oscillation.

See the figure 7A below.

Setting the Pitch/Roll/Yaw gain dials on the Guardian and the Master Gain control on the

transmitter at maximum provides maximum stabilization.

Too high of a gain setting can result in oscillation: see the Oscillations section for

more information on this. Setting Master Gain control to the minimum will lower the

overall gain to zero, while positions in between will yield proportional gain. Lowering the

individual gain dials on the Guardian will lower the gain for that axis only and allow fine tuning.

This might be desirable if, for instance, oscillation is encountered on one axis but not the others.

One possible strategy for setting gains would be to set all three of the individual gain control dials

to maximum and the master to zero. While flying the plane with the Guardian engaged, slowly

turn up the Master Gain and watch for signs of oscillation. If oscillation is encountered, back

down the Master Gain until it ceases. With the plane on the ground, reduce the setting on the

potentiometer for the axis for which oscillation was observed. Repeat until the plane can be flown

with the Master Gain in its middle position without oscillation. If you have a plane with a wide

speed range, such as a hovering 3D aircraft, using this procedure using only the mid range on the

Master Gain will allow you later to turn it even higher when hovering or performing other slow

speed aerobatic maneuvers as oscillation is seldom a problem under these conditions.

If continuous oscillations are experienced with the Master Gain wire disconnected, switch

the Guardian off immediately with the Mode switch if necessary, and land. On the ground, reduce

the gain dial for the oscillating axis as described above.

If connecting the Gain channel on a model where the Guardian had been previously tuned without it, ensure that the position of the Master Gain knob, slider or

switch is set at slightly less than the centered position (see figure 7A) to prevent the possibility of strong oscillations on takeoff.

Oscillations

Sometimes, when the controller gains are set very high or if your model flies at a very high airspeed, oscillations can develop. If oscillations occur, turn down the Master

Gain control or the gain dial for the axis that is oscillating (i.e., the Pitch axis), until the oscillations stop. Other causes of oscillations include mechanical slop in control

surfaces and slow servos. If your model has digital servos, higher gain values may be made possible by increasing the Output Servo Pulse Frequency. See: List of Menu

Features and Options: Output Servo Pulse Frequency.

Oscillation Suppression

To help reduce pilot workload, the Guardian will automatically scale down the Overall Gain when it detects oscillations. To do this, it incrementally scales the Overall Gain

down to a minimum of 50% of its currently set value. After the oscillations are eliminated, it will slowly increase the Overall Gain back up to 100% of its set value or until

oscillations are detected again, whichever comes first.

If oscillations occur and subsequently disappear, it is recommended that you slowly reduce your gains to prevent this from happening in the future.

Do not increase the Overall Gain after an oscillation has been suppressed, since doing so will only cause more oscillations until the Oscillation Suppression is unable to

reduce the Overall Gain sufficiently to be effective.

Preventing Damage to Your Model

In-Air Recovery

The Guardian is a great tool for beginners looking for a safety net in case of lost orientation or control, however switching to 2D Mode with a combination

of too-high airspeed and gains may cause damage to the airframe.

Figure 8: LED Indication during Steady State

Figure 9: Mode/Config Switch

If the model is not structurally capable of pulling out of a steep dive very quickly, some configuration may be needed to prevent excessive G-Forces. Reduce the Overall

Gain (if connected) during high speed maneuvers or limit the travel of the servos through the PC software’s Expanded / Custom Servo Ranges configuration tool under the

“Servo Config” tab. Test your changes carefully and conservatively.

Servo Binding / Stripping

The Guardian may deflect any connected servos beyond the ranges defined in your controller’s servo deflection settings. Exercise caution when first

configuring your model to prevent binding or stripping.

If moving the model or deflecting your control sticks results in any Guardian-controlled servos binding or reaching their mechanical extents, you can limit their movement

in the Guardian PC App by selecting the “Servo Config” tab, setting “Output Servo Ranges Custom” to “On” and assigning specific endpoints for each servo channel. For

more information, please see “The Servo Config Tab” under the “Guardian Configuration Page Software Reference” section.

Tuning for Optimal Gains

While not needed for a good stabilization experience, there is a maximum gain configuration that can be found that will provide the best flight performance with the

Guardian. This entails setting the highest gains for each axis without triggering oscillations. To do this, start out with the individual gain control dials set for their

maximum correct deflections as described in the “Overview/Quickstart” section. Take off with the Master Gain control knob turned down low and once at a safe altitude

and cruise speed, turn it up slowly to enable stabilization. Continue turning it up until an oscillation occurs. Note which axis upon which it occurs, reduce the overall gain,

and land. Reduce the individual dial gain of the axis that was showing oscillations. Repeat this process until all three axes oscillate at the same Overall Gain level or no

oscillations can be triggered.

Status LED

The Guardian’s LED uses blink sequences to convey information about system status, the current flight mode and any errors that have been detected.

LED Indication during Startup

The LED will turn ON for 2 seconds, and then slowly blink the number representing the Model Control Type currently selected (1 blink = Standard, 2 = Elevon, 3 = V-Tail).

See List of Menu Features and Options: Model Control Type for more information. After this startup blink sequence, the LED will display Steady State status as described

below.

LED Indication during Steady State

•Solid On: 3D Mode

•One repeated blink: 2D Mode

•Solid Off: Stabilization Disabled

Additional LED Messages

•2 repeated blinks: Radio Stick Menu is active

•3 repeated blinks: USB is connected

•4 repeated blinks: Error condition. Error type is indicated by a pause

and a number of additional, faster blinks:

oOne blink: Brownout – BEC or receiver battery is

providing insufficient power for your servos and the

Guardian. See the BEC/Receiver Battery Power

Requirements section above.

o2 – 5 blinks: Memory / Calibration Errors – Repower the

Guardian to clear. If this problem occurs repeatedly,

contact technical support.

o6 blinks: Sensor Fault – If this problem occurs

repeatedly, mechanical stress or damage to the board may

have occurred.

o7 blinks: Internal error. If this problem occurs

repeatedly, contact technical support.

Mode/Config Switch Behavior

The Mode/Config input on the Guardian lets you change your stabilization mode in-flight between 2D Mode, 3D Mode and Disabled (if a 3 position switch is used).

Additionally, you can configure the Guardian in the field via a series of toggles of the Mode/Config switch (within 15 seconds of Guardian power up), referred to as

“Configuration Gestures”.

Leaving the Mode/Config input disconnected will cause the Guardian to switch to the Default Flight Mode. The factory default of this setting is “2D Mode.” If you want to

use a different mode in this case, you will need to use the PC software to set the mode, or temporarily connect the Mode/Config input to change the mode via the radio stick

configuration. See the Default Flight Mode menu item in the List of Features and Options section below.

Flight Mode Selection

Please refer to Figure 9. The Guardian has three main operating modes (described earlier) that can be set by the

Mode/Config switch position:

•Down: ( Position 2 , -100%, 1.1ms): 2D Stabilization Mode:

•Middle: (Position 1, 0%, 1.5ms, only available if you are using a 3 position switch): None – No stabilization or

damping. All servo signals are directly passed through. (Elevon and V-Tail mixing is still performed)

•Up: ( Position 0, +100%, 1.9ms): 3D Stabilization Mode

Configuration Gestures

Within 15 seconds after Guardian power-on, the Guardian can be configured by toggling the Mode/Config switch back and

forth rapidly. The number of times you toggle the switch determines which configuration step is performed. Note that if

you have a 3 position switch, its center position is not used during toggling.

The switch you are using on your radio must be configured with its endpoints at approximately -100%, 100% for Configuration Gestures to work correctly.

Figure 10: Menu Navigation and Feedback

Here is a table of available configuration gestures, and what each does:

Reset Level Flight and Trims

: 1 Toggle (up-down if the switch is presently down, or down-up if presently up)

After changing the trims on your controller or mounting orientation, you must let the Guardian know about this change so it can best control your airplane. Without this

information, 3D Heading Lock will not work and stabilization performance will be degraded.

To update the trim and level flight information for your controller in the Guardian, quickly toggle the Mode Switch back and forth once within the first 15 seconds after

power-on. You will know that the level flight orientation and trims have been reset when the servos both twitch once and then immediately return to normal movement.

If no twitch occurs when executing Reset Level Flight and Trims, it can either be because the switch gesture was not done quickly enough or within the first 15 seconds

following boot. Alternatively, if the Guardian is mounted too far off of level flight (greater than 25 degrees in either Pitch or Roll), the Reset Level Flight and Trims will

fail, presenting no servo twitch.

Reset Trims Only:

2 Toggles (up-down-up-down if the switch is presently down, or down-up-down-up if presently up)

Use this gesture to reset your trims without needing to also reset your level flight orientation.

To quickly update the trims of your plane in the Guardian, quickly toggle the Mode Switch back and forth two times within the first 15 seconds following power-on.

(Example: up-down- up-down) You will know that the trims have been reset when the servos both slowly twitch twice and then immediately return to normal movement.

Toggle Elevon Mixing:

3 Toggles (up-down-up-down-up-down if the switch is presently down, or down-up-down-up-down-up if presently up)

A shortcut method for switching between normal and elevon mixed airframes.

To quickly switch elevon mixing on and off without needing to go into the Radio Stick Menu or use the PC software, quickly toggle the Mode Switch back and forth three

times within the first 15 seconds after power-on. You will know that the mode has been changed when the servos both slowly twitch three times and then immediately

return to normal movement. After this, moving your control sticks will reflect the current mixing configuration.

This action will toggle from Normal or V-Tail Mode to Elevon Mode and from Elevon Mode to Normal Mode.

Enter Radio Stick Menu:

4 Toggles (up-down-up-down-up-down-up-down if the switch is presently down, or down-up-down-up-down-up-down-up if presently up).

Enters menu mode (described below).

Radio Stick Menu Operation

The Guardian 2D/3D Stabilizer has many advanced features that can be configured through the Radio Stick Menu.

Entering the Radio Stick Menu

Entering the Radio Stick Menu is done by powering the model with the Guardian connected and

quickly toggling the Mode/Config Switch back and forth four times within the first 15 seconds

following power-on. One second after the last switch movement, the menu will be invoked.

You will know that the menu has been invoked when the servos of your model stop their normal

stabilization deflections and instead perform a short twitch followed by no further movement.

Also, the status LED will blink in a two blink sequence when the menu is active.

Menu Navigation

Once in the menu, you will start at menu item #1 in the List of Features and Options section

below. The menu items can be navigated by deflecting the Aileron and Elevator control inputs

(your control stick). On a controller where moving the stick to the right and pulling it back results

in negative servo deflections (servo pulse width is shortened), flicking the Aileron input to the

right will increase the menu item number currently being edited, while flicking the Elevator input

forward increases the option value for the currently selected item in the menu.

Menu feedback is reported through the Aileron and Elevator servo outputs, as shown in Figure 10.

Each time a new menu item is selected by flicking the Aileron control, the Aileron servo will

“twitch” once, delay 1.5 seconds and then twitch rapidly a number of times that corresponds to the

current menu item number selected. After this, the Elevator servo will count up to the current option value number selected for that menu item. If a new option value is

chosen by flicking the Elevator stick, the Elevator servo output only will twitch once each time the value is changed, wait 1.5 seconds and then count up to the selected

option value number.

If you have your Aileron or Elevator directions reversed on your transmitter, then they will also be reversed as you navigate the menu!

If you have reduced the rates/deflection ranges configured on your transmitter for your servos, ensure that they are deflecting at least 50% in order for

the menu to detect their movements.

Exiting the Menu

To exit the menu, saving the settings that were changed, quickly toggle the Mode/Config switch back and forth once. (up-down or down-up) Once out of the menu, normal

servo deflections will start again, using the new settings.

To exit the menu without saving your changes, simply disconnect the receiver battery and repower the plane. The Guardian will boot up again with its previous settings.

Menu Example

Let’s say you want to set the 2D Heading Hold Gain (menu option 5) to a value of 6. First, toggle the Mode/Config switch 4 times, to enter menu mode, which starts at

menu option 1. Then, you will flick the Aileron stick to the right (or left, if your ailerons are reversed) 4 times, to reach menu option 5. Then, your Aileron should twitch 5

times, to indicate that menu option 5 is selected. And, your Elevator will twitch a number of times, indicating the present setting for the 2D Heading Hold Gain. Then,

flick your Elevator stick up or down, to increase or decrease the 2D Heading Hold Gain setting, until it reaches 6. At this point, the Elevator should twitch 6 times, which is

the desired setting. To save the new setting, toggle the Mode/Config switch once, which exits menu mode, and returns servo control.

List of Menu Features and Options

The following is an ordered list of all the options adjustable in the Guardian’s Radio Stick Menu, and from the PC software. Note that options 14 and higher are available

only via the PC software.

1. Model Control Type

Enables internal mixing if needed. The Guardian expects only an unmixed servo control signal from the Rx.

1: Standard – Dual ailerons / flaperons are supported.

Figure 11: Overall Gain vs. Stick

Position within Center Stick Box

2: Elevon – The Guardian does the elevon mixing internally. Dual Aileron / Flaperon support is not available.

3: V-Tail – The Rudder and Elevator channels are mixed internally. Dual ailerons / flaperons are supported.

2. Center Stick Stabilize Only Mode

This feature is primarily for those who don’t have the Mode/Config switch connected, but want the benefits of 2D mode while also being able to perform acrobatics.

Maximum 2D Mode stabilization is active when the control stick is centered, and as the control stick is moved from center, the Overall Stabilization Gain reduces

proportionally as illustrated in Figure 11. (2D Mode Only)

Radio Stick Menu Options: 1: Off; 2: On

3. Center Stick Box Size

The maximum deflection of the control stick before stabilization is fully disabled in Center Stick Only mode. The

stabilization gain will decrease proportionally with the deflection of the control stick from its centered position. Once

the stick is moved past a certain point, controlled by this setting, stabilization is fully disabled. (2D Mode Only)

Radio Stick Menu Options: 1-10: Center Stick Box Width

4. Automatic Turn Coordination

Employs the “Step On The Ball” method to move the Rudder in order to coordinate your turns in 2D Mode. For more

information, see “Automatic Turn Coordination” under the “Main Features”/“2D Mode” section. (2D Mode Only)

When taxiing in 2D Mode on an incline, this feature will try to yaw your model down the hill. Additionally,

if the Guardian is not very close to the center of gravity, then this feature can increase the chance of Yaw

oscillations.

Radio Stick Menu Options: 1: Off; 2: Low; 10: High

5. 2D Heading Hold Gain

When the control stick is centered horizontally (zero Roll command) in 2D Mode, the controller will roll the plane to

track its current heading. (2D Mode Only)

Radio Stick Menu Options: 1: Off; 2: Low; 10: High

6. Direct Rate 3D Control

When in 3D Mode, the plane will react much more precisely with this feature enabled. Instead of simply stabilizing the 3D flight, it will control the rotational rates of the

plane directly. This provides very strong disturbance (wind, airframe inertia, etc) rejection without having to “fight the gyro”. (3D Mode Only)

This feature will expand your servo deflections beyond any limits set on your transmitter, up to the limits set by the Guardian. See Expanded / Custom Servo

Ranges for more details on how to limit servo deflections.

Radio Stick Menu Options: 1: Off; 2: On

7. Enable 3D Heading Hold

Enables the 3D Heading Hold feature in 3D Mode. Those looking for the stability and precision of the Guardian without anything else getting between them and their

airplane can disable this feature for a rate-gyro experience. (3D Mode Only)

Enabling Direct Rate 3D Stabilization is strongly recommended if this mode is set to “Off”.

Radio Stick Menu Options: 1: Off; 2: On

8. Derivative Gain

Tunes the dampening/derivative gain of the airplane. Increasing this value will strengthen the “rate gyro” behavior of the Guardian while leaving the 2D leveling and 3D

Heading Hold behaviors the same.

Increasing this value without reducing your overall or individual axis gains will increase the chance of oscillations.

Radio Stick Menu Options: 1: Low Derivative; 10: High Derivative

9. Onboard Dual Aileron Mixing Enabled

Configures the Guardian to accept unmixed Aileron and Flap (Aux In) inputs and mixes them internally to provide Dual Aileron / Flaperon outputs on Ail and Aux Out. If

disabled, the Guardian will accept premixed Flaperon signals. Useful with limited controllers that cannot perform Flaperon mixing. Disabled by default.

Radio Stick Menu Options: 1: Off; 2: On

10. Aux Servo Output Reversed

Reverses the direction that stabilization will move your second Aileron servo if you are using the Aux channel in a Dual Aileron configuration.

Radio Stick Menu Options: 1: Off; 2: On

11. 2

Elevon Reversed

Set this if the second Elevon servo on a “Delta” wing plane is not symmetrically mounted and is resulting in incorrect servo movements.

Radio Stick Menu Options: 1: Off; 2: On

12. Expanded / Custom Servo Ranges

Allows advanced users to expand the functional range of their servos from 125% around their trim values to 150% around their trim values. Overall servo deflection range

is expanded to 175%, including trims. When configured on the PC software, this option also enables custom servo limits that can be set there.

This can damage your servos and your plane if activated carelessly. It is included for modelers that either need the extra range or wish to limit the ranges to their

servos. Make sure to reset your trims before activating this mode!

Radio Stick Menu Options: 1: Off; 2: On

13. Default Flight Mode (For when Mode/Config switch is unused/disconnected)

If you don’t have the Mode input channel connected during flight, the Guardian will use the flight mode selected here. Note that you will need to set this with the PC

Software, or temporarily connect a switch to the Mode input channel to set it.

Radio Stick Menu Options: 1: 2D Mode (default); 2: 3D Mode

14. Output Servo Pulse Frequency (PC Software Configuration ONLY)

Sets the pulse frequency of the servo signals going out of the Guardian. A default of 50 Hz is recommended for analog servos, but some digital servo support higher