Soft mount – So, what is it?

The FPV Drone community is on fire because of the new hype: Soft mounts. The source of this hype was when the Drone Racing pilot Johnny FPV stated his secret is to soft mount the motors so it flies like it’s on rais.

But what exactly are soft mounts? It’s just hype or it really make some difference?

Soft mount is nothing more than fix motors in the drone arms using some soft material between the motor and the arm, with the purpose of absorbing the vibration and reduce as much as possible before it reachs the gyroscope in the flight controller board.

When first quadcopters have came out, it was a commom practice to mount the flight controller board on a damped surface, usually by rubber or silicon mounts. At these times gyroscopes was not so good, so any vibration caused a huge noise on the position reading.

As the gyroscopes and processing power of flight controllers evolved, the vibration generated noise was reduces, and complex filtering algorithms were created and did a excellent job filtering the remaining noise. But it have a cost, and it is processing cycles.

On the most modern flight controller boards, the gyroscope are even faster than before, reaching refreshing rates up to 32kHz, and with faster operation frequency comes noise, and flight controller have to work harder to know what is legit movement and what is just noise.

Minimize vibration that reaches the flight controller is a good way to get more performance from gyroscope, because it allows you to reduce the filter algorithm and it reduces A LOT the processing load. One way to do it is avoid the vibration of motors affect the drone frame and end up reaching the flight controller board.

So, in teory, soft mounting motors really can help to fly better, more “locked in” and with sharp responses to the transmitter commands.

The Friend Ultra FPV did a nice video demonstrating the difference of accelerometer values in both situations: With and Without soft mounting motors.

So, any doubt? Leave a comment!

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