Control Loop arducam Motor Specs

Hello everyone! I recently purchased the Arducam imx519, and I’m thrilled with its performance. I’ve had the chance to test the autofocus function as well as manually adjust the lens position and explore its capabilities.

Now, I’m interested in delving deeper into controlling the motor responsible for lens movement using control theory. I was wondering if there are any publicly available specifications regarding the dynamics or transfer function of this lens motor. In simpler terms, if I have an initial condition x(0) and a control action signal u(t), is it possible to determine the current state x(t) by utilizing the motor dynamics equation x’ = f(x,u)? Any insights or information regarding these dynamics or transfer functions would be greatly appreciated.

Additionally, I’d like to know where I can locate the current control loop used for the autofocus feature within the libcamera-still library. If anyone could point me in the right direction, I would be grateful. Thanks!


We are currently using the formula provided by the Raspberry Pi, and I am not too clear about the very principle.

You can refer to their source code, or ask the Raspberry Pi directly for the content of the relevant formula.

Thanks so much Edward,