Gremsy Mio, Pixy, S1, T3, T7, and ZIO 3-Axis Gimbals¶
Gremsy Mio, Pixy F, Pixy U, Pixy WP, S1, T3, T7 and ZIO 3-axis gimbals can communicate with the flight controller using the MAVLink protocol and are compatible with a range of cameras for real-time video or mapping purposes.

Where to Buy¶
These gimbals can be purchased from the Gremsy store
Connecting to the Autopilot (4.3 or higher)¶
If using ArduPilot 4.3 (or higher) please follow these setup instructions

Connect the gimbals’s COM2 port to one of the autopilot’s Serial/Telemetry ports like Telem2 as shown above.
Connect to the autopilot with a ground station and set the following parameters, if using the first mount:
MNT1_TYPE to “6” for “Gremsy” and reboot the autopilot
SERIAL2_BAUD to “115” for 115200 bps. “SERIAL2” can be replaced with another serial port (i.e. SERIAL1) depending upon the physical connection
SERIAL2_PROTOCOL to 2 for “MAVLink2”
SERIAL2_OPTIONS to 1024 for “Don’t forward mavlink to/from”
Optionally set RC9_OPTION to 163 for “Mount Lock” to allow the pilot to switch between “lock” and “follow” modes during “RC Targetting”. Note “RC9” can be replaced with any RC input channel
When the autopilot has successfully connected to the gimbal, “Mount: GREMSY PixyU fw:7.7.1.0” (or similar) will be sent to the ground station. Looking for this message may be useful in determining if the autopilot and gimbal are communicating successfully.
Configuring the Gimbal¶
Download and install gTune Desktop
Connect the gimbal to your Desktop PC using a USB cable and power on the gimbal
Use gTune Desktop to check the gimbal firmware version
Open gTune Desktop application, “Found your device” should be displayed
Select “CONNECT”
Select “INFO” and confirm the gimbal is running Firmware “7.7.1” or higher
If the gimbal firmware is older than 7.7.1 download the latest .hex for Mio, Pixy F, Pixy U, Pixy WP, S1, T3, T7 or ZIO
Select “UPGRADE”, “BROWSE” and select the file downloaded above
Press the other “UPGRADE” button and the upgrade should complete within 30 seconds
Use gTune Desktop to configure the gimbal
Select “SETTINGS”, “CONTROLS” and ensure “SYNC” is selected so the gimbal communicates with the autopilot using MAVLink
Select “Settings”, “REDUCE DIRFT by DRONE”
Select the “STIFFNESS” tab and adjust the Tilt, Roll, and Pan gains so that the gimbal holds the camera in position without shaking
Testing Controlling the Gimbal from RC¶
Disconnect the USB cable connecting your PC to the gimbal
Powerup the vehicle and gimbal
Move the transmitter’s channel 6 tuning knob to its minimum position, the camera should point straight down
Move the ch6 knob to maximum and the gimbal should point upwards
Note
The RC’s channel 6 input can be checked from Mission Planner’s Radio calibration page
Testing ROI¶
The ROI feature points the vehicle and/or camera to point at a target. This can be tested by doing the following:
Ensure the vehicle has GPS lock
If using the Mission Planner, go to the Flight Data screen and right-mouse-button-click on a point about 50m ahead of the vehicle (the orange and red lines show the vehicle’s current heading), select Point Camera Here and input an altitude of -50 (meters). The camera should point forward and then pitch down at about 45 degrees

Pilot control of the gimbal can be restored by setting up an auxiliary function switch to “Retract Mount” (i.e. RCx_OPTION = 27) and then move the switch to the lower position
Connecting Two Gimbals¶
If two Gremsy gimbals are used, each gimbal can be directly connected to one of the autopilot’s serial ports or they can can be daisy-chained together with only one connected to one of the autopilot’s serial ports.
Use the gTune desktop application set the second gimbal’s MAVLink component id to “GIMBAL_COMPID2”
Connect a GCS to your autopilot and set
MNT2_TYPE to “6” for “Gremsy” and reboot the autopilot
set the appropriate SERIALx_BAUD, SERIALx_PROTOCOL and SERIALx_OPTIONS parameters as described above
Connecting to the Autopilot (4.2 or earlier)¶

We recommend connecting the Gimbals’s COM2 port to one of the autopilot’s Serial/Telemetry ports like Telem2 as shown above.
Connect with a ground station and set the following parameters, if using the first mount:
MNT1_TYPE to “4” for “SToRM32 MavLink” and reboot the autopilot
SERIAL2_BAUD to “115” for 115200 bps. “SERIAL2” can be replaced with another serial port (i.e. SERIAL1) depending upon the physical connection
SERIAL2_PROTOCOL to 2 for “MAVLink2”
SR2_EXTRA1 to 10
SR2_POSITION to 10
The gimbal’s maximum angles can be set using these parameters (shown for the first mount):
MNT1_ROLL_MIN to -30 to allow leaning left up to 30deg
MNT1_ROLL_MAX to 30 to allow leaning right up to 30deg
MNT1_PITCH_MIN to -90 to allow pointing 90deg down
MNT1_PITCH_MAX to 30 to allow pointing 30deg up
MNT1_YAW_MIN to -180 to allow turning around to the left
MNT1_YAW_MAX to 180 to allow turning around to the right
To control the gimbal’s lean angles from a transmitter set the RC controls for roll, pitch, or yaw using RCx_OPTION
212 (Mount1 Roll), 213 (Mount1 Pitch), 214 (Mount1 Yaw) for the first mount, or 215-217 for the second mount, respectively.
Gremsy’s instructions can be found below: