servo triggered by a motion senor powered by 240v


I am currently working on a project where I would like a servo to be triggered by a motion senor.

The mechanism will be used for relatively long periods, having it powered by 240v so it can be plugged into the wall would be ideal. I imagine I could use a PIR montion sensor that's wired to an Arduino board that then controls a servo. I also imagine it's a lot easier to write that last sentence than to achieve.

Essentially I want to be able to plug the project in, and then when someone walks past it activates the servo.

For the servo I would need the it to move a few kilos, and I would need to be able to adjust the speed of it for example fast in one direction and slowly for its return to the starting position. I would also like to be able to make the servo turn 360 degrees, it doesn't have to spin continuously, but I would like to have the ability to make it turn a full 360.

I haven't started building, so if anyone has ideas regarding if this is possible, and some insights that would be brilliant.



Moving "a few kilos" is not your typical RC Servo. That would require a big motor or one of the really big and strong robotics servos.

A low voltage Passive Infra Red (PIR) sensor would be easier to interface to an Arduino. They are available from Adafruit, Sparkfun, eBay and all the Chinese outlets. Adafruit has a good tutorial. I have not played with the mains powered PIR sensors. I bet they could be used with rectifier and a level shifter or voltage limiting circuit.