In some embodiments, a camera actuator module includes a linear actuator motor for moving a lens assembly, a position sensor coupled to the lens assembly, a mechanical end stop mounted in the path of motion of the lens assembly, and a non-transitory storage medium storing program instructions. In some embodiments, the program instructions are computer-executable to implement exciting, using the linear actuator motor, a mechanical resonance in the camera actuator module calculated to cause the lens assembly to move to an overload displacement by powering the linear actuator of the camera actuator module at a resonant frequency of the camera actuator module, measuring, using the position sensor, a current maximal displacement of the lens assembly during the exciting using a position sensor, and estimating a position of the mechanical end stop using at least the current maximal displacement.