Futaba GY470 Rate Gyro for Helicopters

Features of GY470

• Remote gain function and mode switching function: Adjust gain from the transmitter or with the trimmer on the GY470. Supports AVCS/NORMAL gyro mode switching.
• Integrated, compact, and lightweight: 20.7x20.7x11mm, 3.7g, realized by high-density mounting technology.
• Easy setup: Usable immediately with minimum setup.
• Supporting the S.BUS/S.BUS2 connection: Single wire connection to the receiver.

GY470 Ratings

• Gyro sensor: MEMS vibrating structure gyro
• Operating voltage: DC 4.0 V to 8.4 V
• Current drain: 30 mA (excluding servo)
• Operating temperature range: -10 °C to +45 °C
• Dimensions: 20.7 x 20.7 x 11.0 mm (excluding protrusions)
• Weight: 3.7 g
• Functions: Sensitivity trimmer, LED monitor, Servo selection (1520 µS, 760 µS), S.BUS/S.BUS2 connection.

Functions

• Servo Selection Switch
• Gyro Direction Switch
• Port 3 (Rudder output)
• Port 2 (Gain input)
• Port 1 (Rudder input/S.BUS input)
• Trimmer (Limit / Gain)

Set Contents

• GY470
• Mini screwdriver
• Wiring strap
• Sensor tape
• Extension Cord: (Black)
• Extension Cord: (Red)

Connecting the GY470

Standard Connection:

• Connect Port 3 (Rudder output) to the rudder servo.
• Connect Port 2 (Gain input) to the gyro gain CH of the receiver for remote gain. If not connected, the trimmer on the GY470 functions as GAIN.
• Connect Port 1 to the rudder CH of the receiver.

S.BUS Connection:

• Connect Port 1 to the S.BUS receiver.
• Port 2 is not connected. Remote gain is still effective.
• Connect Port 3 to the rudder servo (digital servo only).

Mounting to Fuselage

• Always use the accessory sensor tape to install the GY470, placing it at the center of the tape.
• Check the sensor installation state before flight. If the sponge is torn, replace it.
• Clean any oil from the sensor bottom and the installed part of the frame with cleaner.
• Install the sensor so that the bottom of the gyro is perpendicular to the main rotor shaft axial direction. Offset of this axis may react in the roll and pitch directions.

Rudder Servo Linkage Check

In NORMAL mode:

• Make initial linkage connections in NORMAL mode. Adjust mechanically and use minimum trimmer adjustments at the transmitter.
• Move the rudder stick left and right. Check the direction of operation of the tail rotor. If it operates in the wrong direction, reverse it using the transmitter's reverse function.
• At the rudder neutral position, connect the linkage so that the servo horn and control wire are perpendicular.
• Set the servo horn length according to the helicopter manufacturer's instructions.

Monitor LED Display

WARNING

• Always check transmitter and receiver battery voltage for sufficient capacity.
• The GY470 requires 3-5 seconds to initialize. Do not move the helicopter or rudder stick during initialization. If the neutral has shifted, the LED will blink orange, indicating a reboot is needed.
• Ensure slack in gyro cables for maximum performance.
• Use supplied gyro mounting pads. Do not use a strap that encompasses the GY470 sensor, as it may affect performance.
• When switching between NORMAL and AVCS modes in flight, re-learn the center position by flipping the gain switch three times (NORMAL → AVCS → NORMAL → AVCS → NORMAL → AVCS) within one second. The servo will center, indicating the new center position is memorized.
• Use only digital servos with the GY470. Using an analog servo will damage it.
• Always check servo operation direction. Incorrect direction can lead to dangerous flight.
• Do not drop the GY470 or subject it to strong shock, as this may damage the sensor.
• When using AVCS mode, set revolution mixing to OFF.
• Do not place the gyro near heating equipment. Allow the gyro to adjust to ambient temperature before flight. Significant temperature changes during use can cause drift.

Adjustments

Please consider both helicopter and transmitter directions.

Setup before a flight [Remote gain use]

Requires S.BUS connection or gyro gain CH of Port 2 connected to the receiver.

1. Set the servo selection switch to your tail rotor servo setting (1520µS or 760µS).
2. Set up your transmitter according to the gyro setting menu manual. Gyro gain is set to 50% by AVCS. Refer to the graph for AVCS/NORMAL mode or LED status.
3. Turn on the receiver. The GY470 requires 3-5 seconds to initialize. Do not move the helicopter or rudder stick during initialization. If the neutral has shifted, the LED will blink orange, indicating a reboot.
4. Move the rudder stick left and right. Adjust the limit trimmer for maximum travel, ensuring the servo horn does not hit the linkage.
5. Check gyro direction: If the rudder servo moves Right when the helicopter nose moves Left, the direction is correct. If the rudder servo moves Left, switch the direction using the Gyro Direction Switch.

Setup before a flight [Remote gain not use]

When not using S.BUS connection and Port 2 is not connected. The limit trimmer is automatically changed by the gyro gain setting trimmer. Limit is fixed at 50 degrees left and right.

1. Follow steps 1-3 from the remote gain use section.
2. Gain trimmer operation: Start with AVCS set to 50%. Adjust the gain trimmer gently.

Flight Adjustments

• Adjust the transmitter and gyro while repeatedly taking off and landing with the aircraft on the ground. Transmitter adjustments should not be made while flying.
• Set sensitivity to prevent hunting during hovering and flight.
• Adjust hovering and flight rudder effect using the transmitter's D/R or AFR function. Do not use the End Point (ATV) function, as it may change trimming.

AVCS/NORMAL Mode

NORMAL Mode: Sends control signals to the rudder servo only when the helicopter tail moves. When the tail stops moving, the gyro signal becomes zero. This results in a "weathervane" effect where the helicopter tail drifts with crosswinds, and the gyro repeatedly corrects the drift.

AVCS Mode: Continues to send control signals to the servo even when the tail stops moving. The gyro computes drift angle and constantly outputs a signal to resist crosswinds, automatically correcting tail trim (auto trim). When the tail rotates, the servo rotates accordingly. When the tail stops, the servo holds that position.

AVCS Mode Servo Neutral Position Check: If the rudder stick or helicopter is moved in AVCS mode, the servo may not return to neutral. To check: Move the rudder stick fully left and right within 1 second, then return to neutral. The servo will move to the neutral position after about 1 second.

What is S.BUS?

S.BUS is a data communication system that transmits control signals from a receiver to servos, gyros, and other compatible devices. It allows commands to be sent to multiple devices on the same signal line. S.BUS devices execute commands for their set channels. Channels for S.BUS servos can be set using an SBC-1 channel changer or CIU-2 USB serial interface. Conventional servos can be used, but they cannot be used with S.BUS output.

Important Notes for S.BUS:

• Turn on the transmitter power first, then the receiver. Confirm operation to avoid malfunction.
• Wiring for S.BUS servos should only be replaced when power is OFF. Replacing wiring with power ON can lead to malfunction.