Ways to automatically swing or rock a baby

Question

An idea that comes to my mind to swing a baby swing automatically is using a CD drive eject - close function , I have several such Drives I dont use and I dont want to use a computer to do the periodic control eject \ close. Can it be done without a controller or just a simple circuit? Also, are there any other ways to make the swing automatic , what I need is just a back and forth motion to couple it with the swing?

Here is the typical swing:

Also we have a rocker like one below can it also be automatized?

Note: Some babies wont just sleep unless they are swinged\rocked continuously hence the question. And I know automated stuff is available but we already have these non automatic stuff.

Update:

I had asked a similar question here

Answer 1

Rocking a baby in a swing or rocker takes a fair bit of torque, hence it's not a trivial problem. Above all other things you want to make it absolutely safe and make sure that no curious baby fingers or toes can get trapped or squeezed in any way form or shape.

I would recommend against doing this yourself and go with a commercial product that has been properly tested and is UL (or equivalent) certified.