I am a complete noob when it comes to electronics, but would love to learn as a hobby.
I would like to build a motion activated water sprayer, but have no clue as to the additional circuitry would be needed. Would anyone be able to help or point me in the right direction?

Kind Regards,

 

You might enjoy this project. One of the best ever.

 

Welcome to AAC.

We can certainly help, but we need a lot more information first.

What kind of sprayer are you thinking about? A garden hose, a battery-powered sprayer, or something you plan to make yourself? If the latter, what are the voltage and current requirements of the pump motor?

Here are some small battery-powered ones:

http://www.amazon.com/Scrubbing-Bubbles-Extend-A-Clean-25-Ounces-1-Starter/dp/B00343FRHG

http://store.reuseum.com/Battery_Po...mp-RS004.htm?gclid=CNzErLiU-rMCFYKK4AodomsAwA

What do you want it to do?

You mentioned motion-activated, so how would you like it to operate? Think about it step-by-step. As an example:

1) Motion detector, when triggered by movement, triggers sprayer - a) immediately, b) after a delay of xx seconds, c) other?
2) Sprayer sprays for a) xx seconds, b) until motion detector stops detecting motion, c) other?
3) Delay between motion detections? In other words, do you want the sprayer to remain off for xx seconds/minutes after it has sprayed once so multiple motion detections in a short period of time don't continue to trigger it?

I just helped someone here do something similar with a PIR module from Parallax: http://www.radioshack.com/product/index.jsp?productId=12330342.