ESC Open Loop Commutation Time Effects on Stability

Hello - I am considering getting a BlueRov and I am wondering how well the stabilization actually works. As far as I understand the thrusters are BLDC motors driven with zero cross detect based 6 step ESCs. This thus means that the ESCs have a minimum operating speed. To maintain stability they must be driven bidirectionally, but this minimum speed means that there is a deadband in which they cannot run correct? I’m wondering if this creates a kind of “hunting” around each axis of control? I’ve seen some videos of them generally stabilizing /heading holding, but I’m thinking this probably isn’t very exact? Would anyone happen to have any detailed videos of the thrusters maintaining heading / stability? Thanks in advance!

Hi @finfish -
The deadband is not an issue, I’ve never witness the “hunting” you describe! The BlueROV2 does a great job holding heading and orientation - the thrusters quickly fight any external forces. You can find some videos on this playlist.

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