Question about an art project

I'm trying to make an interactive sculpture and I'm wondering if using Arduino is the way to approach it. I need to have an air pump that is activated by a motion sensor. When the sensor is activated I need the pump to inflate for 10 seconds and then stop. Has anybody done something like this in the past? Do you have any advice? I have no experience with engineering of any kind, any comments would be greatly appreciated.

What are you inflating? This would determine what pump you need which would determine what circuit you need.

I made a balloon of sorts. It's a sheet of dragon skin rubber with a plexiglass backing so only one side inflates. I have a small air pump from walmart (used for inflating pool toys) that works just fine.

briannab:
I made a balloon of sorts. It’s a sheet of dragon skin rubber with a plexiglass backing so only one side inflates. I have a small air pump from walmart (used for inflating pool toys) that works just fine.

What are the pump’s specs? ie Voltage, current. Is it a DC pump, or mains AC?

A little searching and reading will soon teach you how to connect and read a movement sensor, and also how to make a digital pin high for 10 seconds, so all that remains is the interface between the Arduino and the pump.

How will the object be deflated?
Another point, I guess you’ll need to ensure that the pump can’t be activated more than once without deflation between times.

120v .95a
It's AC

You'll need a relay, relay module or solid-state relay to switch mains voltage with an Arduino. A solid-state relay would be the most convenient, but also the most expensive.
How do you plan to power the Arduino? Battery? Wall-wart?

Have you put any thought into avoiding over-inflation, as I mentioned? (You didn't address the other points that I raised.)

"You'll need a relay, relay module or solid-state relay to switch mains voltage with an Arduino. A solid-state relay would be the most convenient, but also the most expensive.
How do you plan to power the Arduino? Battery? Wall-wart?"

I'm not sure. What do you recommend?

"Have you put any thought into avoiding over-inflation, as I mentioned?"

As far as over inflation is concerned, with the air pump that I have 10 seconds of airflow is perfect to inflate the balloon to the ideal volume. As long as it deflates fully after each inflation it should be fine.

"How will the object be deflated?"

Right now in my test runs (without the arduino) I have it set up in such a way that there are small vents throughout the balloon. Once the pump stops running, the air escapes.

"Another point, I guess you'll need to ensure that the pump can't be activated more than once without deflation between times."

This is a good point as well. I wonder if it would be more successful if rather than a motion sensor, I had it hooked up simply on a timer. So that it would inflate and deflate on a set schedule? Do you think this would make my idea more plausible?

You can inflate and deflate on a schedule with simple code in an Arduino.

A wall-wart is the easiest way to power things, since then you don't have to worry about battery charging/replacement.

There's nothing wrong with triggering inflation using a movement sensor, but a set schedule would definitely be simpler. (Almost too simple.)

Otherwise, after inflation, the PIR detector could be ignored for a period to allow for deflation, since you're using slits for automatic deflation.

You just need to do a little thinking and decide exactly which way you want to go with things.

Does the Arduino need to do anything else?