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Help Needed: How to use Arduino to Power a Motor and 4 PIR Motion Sensors as Switches? Answered

Hello all! I am in need of help. I'm making sculptures that I want to rotate when people walk by. The sculptures will be about 4 1/2 feet tall but light, about half a pound. I want them to spin slowly, around 1-2 rotations per second. 

I am hoping to use an Arduino to power a DC motor (or a stepper motor is ideal because it's easier to find one with a flat bottom, but I understand it's also more electronically complicated). I want to use four PRI sensors (one on each side of a square base) as switches to turn on the motor when people walk by. I want to code the Arduino to turn off the motor after about 7 seconds, and the turn it back on if the sensor is triggered again. 

I am open to suggestions on every level of this project, including which materials to use, schematics, battery power and code. I've been messing around with it for a while, but I basically feel like I need someone to walk me through it. I've gotten one PRI hooked up to work, but I have no idea how to connect a second, third and fourth, or how to plug it all into an external battery source (a motorcycle battery, a gel cell battery have both been suggested to me, but I'm worried that might be too much power?)

Currently I have an Arduino R3 Plus, Osepp and Raspberry PRI sensors, a 12V DC motor, a 12V stepper motor and various other wires and resistors to hook it all up. 

Do I need a larger Arduino? What kind of battery power do I use?

Any help you can give me would be so Appreciated!! 

Thank you very much, 


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4 years ago

There are probably some instructables on motion trackers

This one popped up in search on the web


You need a motor shield to interface a motor with an arduino so you don't burn out your board. Take a look at robotic projects with geared motors and then you can see what kind of power source to use. Good luck.