Context: I am building an add-on to a door handle to create a "smart door handle" that I can move remotely. Working in IT, the software part is not a problem, but the mechanical one is. I am considering several solutions and one of them involves gears. I apologize in advance for my technical wording, not being a native speaker of English (and neither a mechanical engineer).
The generic idea is to have one gear mounted directly on the door handle axle
source: my first attempts to use the fantastic FreeCAD
It will be powered by a stepper motor via either a smaller round cogwheel or a worm gear (I am not sure which yet).
The problem: I need to be able to manually press on the handle to open the door (with my hand). With the simple solution I have so far it is not possible: pressing on the handle would force the movement of the wheels and this is not good either mechanically (the torque will be too big and probably break/damage the wheels) or electronically (the motor is not intended to work as a generator, and even if it was the torque is not correct).
The sought-for solution: a mechanism that would make it so that a movement triggered by the motor moves the handle, but when the handle is pressed and it is the source of the movement - it would not be transferred to the motor.
I thought that this was a showstopper but after watching 20 Mechanical Principles combined in a Useless Lego Machine I realized that I have no idea about what is possible in mechanical engineering.
My question: is there a standard solution for such a problem?