Any Electronic Gurus around?

[Emphasiski]

I'm planning a pretty involved prank. Half of it, is my supervisor cleaning up the mess. So it needs to happen when I'm not there.

Basic electronic components are abundant at work...wires, switches, photocells, SCR's etc.

We have basic ceiling tires at work. When my supervisor sits, or does something at his desk...I want a tile to lift and a box of super fine paper shredding to get dumped on him.

I'm fine with a couple servos and some fishing line doing this, but what I can't figure out is a delay between the servos. So one can lift the tile, and the other can tip the container with the shreddings.

I'm also open to switch ideas. I have some photocells and SCR's I could use, but there's nothing guaranteeing that he's going to be in one spot. So I might put a microswitch on the bottom of his chair, for when he sits in it....maybe a pull switch, for when he pulls his chair out to sit in it...hmmm

 

[Gollnick]

I'm fine with a couple servos and some fishing line doing this, but what I can't figure out is a delay between the servos. So one can lift the tile, and the other can tip the container with the shreddings.

Ah yes... the elements of time and of sequence. Do A. Wait for B. Then do C.

For this to really work well, you will want to wait for the chair sensor, then activate the motor to raise the ceiling tile, then wait for the tile to open, then activate the motor to dump the confetti, then wait for some time for the confetti bin to empty, then reverse the motor on the bin, then wait for the bin to return to the initial position, then reverse the motor on the tile to close the tile, then stop.

You can introduce simple time delays with time-delay relays. But the more complicated behavior described is best achieved with a PLC, programmable logic controller.

 

[Emphasiski]

I was hoping to stay away from getting a controller. I'm assuming you're referring to something like an arduino board.

 

[Emphasiski]

Although, with the cost of some of those relays...I might be better off getting and arduino.

 

[Gollnick]

An arduino board is a microcontroller. It would be fun to learn on. But it's steep learning curve. It's also going to take work to interface it to your other components.

PLCs are not cheap -- except used on eBay. They do range in price considerably; what you need here is a very simple one which should be very inexpensive. They're easier to work with both to program and to interface. And, they are actually made for doing just this sort of thing.