How can I gently swing closed a swinging glass door?

At the entrance to my office, we have these two glass doors that swing open (with a bit of resistance) and they automatically close slowly behind you. If you open them all the way (so, perpendicular to their normal position), they stay open. I wanted to give our office manager the ability to remotely close the door without having to go down two flights of stairs.

So I was thinking that a solenoid wouldn’t work, because it’s too fast and could shatter the door. But I need something that can go slowly, but also has enough force to push past the “thing” that keeps the door in the open position, to get it to close on its own.

Obviously this thing whatever it is would be controlled by an Arduino. I already built a board that uses a distance sensor to detect if the door is in the fully open position.

Any ideas?

Thanks!

How much force and how far do you need to push to get past the detent? How would the force be applied? Linear as a push or pull or angular like a sweeping arm?

I don't have the right equipment to measure the force, but I would say roughly the same effort it would take to lift a 5lb weight, and it has to go about 1-2 inches.

How would the force be applied? Linear as a push or pull or angular like a sweeping arm?

When the door is propped open, it's parallel to the wall where I've mounted my sensor box. The distance between the door and the wall is approximately 6 inches. So the force would ideally be applied "straight on," perpendicular to the door (and wall). It would give it a nudge, and the door would close (as the door was closing, the "piston" would end up at an angle to the door as the door closes).

Use a linear actuator. There are many different types, and they can move at any speed you like.

The door has a hydraulic door closer with detent. the detent is a small ball with a spring and the shaft has a small dimple or detent.

Any way you can move the door would allow the detent to be passed so the closer could close the door.

you are correct that you only need to push the door slightly.

Can install a stop to prevent the door from going that far ? how close is the nearest wall ? can you mount a motor with arm?

to test force, get a bucket and string and a pencil and some water tie the bucket to the door, loop the bucket over the pencil and start to fill the bucket with water stop when the door moves. weigh the bucket.

I am thinking a small motor on the wall near the top of the door. motor can be slow,