Using STorM32 with DJI

The STorM32 gimbal controller can communicate with an DJI flight controller via the CAN bus. The CAN bus communication allows for a much richer set of features than possible with the traditional PWM connections. Examples are advanced control functions or the STorM32-Link. It also leads to a clean wiring.

Currently only the DJI Naza M2 is supported.

STorM32-Link Features

The DJI CAN bus STorM32-Link provides 3 features:

• Control of the STorM32 functions by the radio transmitter. This feature has the same effect as if the receiver would be connected to the STorM32 controller at its inputs, except that such a physical connection is not required since the information is read off from the DJI CAN bus. For this to work the parameter Virtual Channel Configuration in the [GUI:Setup] tab must be set to “serial”.
• Yaw drift compensation. This feature suppresses any yaw drift of the camera IMU. This allows one e.g. to put the yaw axis into “hold” mode for extended periods of time, and yet the camera will not drift away (the accuracy and stability depends on the accuracy and stability of the flight controller's yaw angle).
• Horizon drift compensation. This feature helps to maintain a leveled horizon even in high-g maneuvers, there the horizon would usually tilt. For this to work the parameter STorM32Link Configuration must be set to “v1”.

A demo video showing the effectiveness of the horizon drift compensation is available on the firmware author's youtube channel.

Testing the Connection

The CAN bus connection can be tested in several ways. The following tests do not require that the copter is completely built, and do not require that the copter is armed.

• STorM32-Link field in the STorM32 GUI: The [GUI:Dashboard] and [GUI:Data Display] each have a field which is related to the STorM32-Link. They should display OK, PRESENT or a similar positive message.

• Gimbal RC Targeting: The camera can be moved with the transmitter sticks.

• Sniffing the communication: One of course can sniff directly what is going on on the CAN data lines. You when need a SLCAN adapter, e.g., the UC4H SLCAN adapter.