SimpleBGC Gimbal (aka AlexMos gimbal)

The SimpleBGC is a popular brushless gimbal controller that can communicate with ArduPilot (Copter, Plane, and Rover) using MAVLink or a custom serial protocol. More details on the capabilities of this gimbal can be found at basecamelectronics.com

More details can be found in the software user manual.

Where to Buy

The SimpleBGC controller and accompanying 2-axis and 3-axis gimbals can be purchased from basecamelectronics.com and many other retailers.

Connecting the gimbal to the Autopilot

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Although the SimpleBGC can be connected using PWM we recommend using the serial interface connected to one of the autopilot’s Serial/Telemetry ports like Telem2 as shown above.

Configuration when using Custom Serial Protocol

In your Ground Control Station set the following parameters, if using the first mount connected to Serial2 as shown above:

If you are unable to connect you may wish to set the following parameters although normally this should not be required:

  • SERIAL2_BAUD to 115 (means use serial baudrate of 115200)

  • BRD_SER2_RTSCTS to 0 to disable flow control on Telem2 (use BRD_SER1_RSCTS if connecting to Serial1, Serial4/5 never uses flow control)

The gimbal’s maximum lean angles can be set using these parameters:

Control and Testing

See Gimbal / Mount Controls for details on how to control the gimbal using RC, GCS or Auto mode mission commands

Testing the gimbal moves correctly

Testing the pilot’s control of pitch

Once powered the gimbal should point to its Pitch Angle Min (i.e. straight down) when your transmitter’s channel 6 tuning knob is at its minimum PWM value (perhaps around 1000) and the camera should point to its maximum pitch angle (i.e. straight forward) when the tuning knob is at its maximum (perhaps around 2000). The Mission Planner Radio calibration page can be used to check the Ch6’s current input PWM value.

Testing ROI

You must have a GPS lock to test ROI. The ROI feature points the vehicle and/or camera to point at a target. The instructions above describe setting up the APM/Pixhawk so that it only controls the pitch of the Tarot gimbal so when a Do-Set-ROI command is received Copter will attempt to turn the vehicle’s nose to point in the direction of the target and pitch camera depending upon the vehicle’s distance and altitude. You can test the gimbal pitch moves correctly by connecting with the mission planner, then on the Flight Data screen’s map, 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). This should cause the gimbal to point down at about 45 degrees.

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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