I’m working on a project that will turn a small motor on or off, depending on the light level detected by a photoresistor working with an LED. The motor will need to be strong enough to turn a small spool of paper, and I plan to use gearing as needed to reduce the speed of the motor to about 60 rpms. The project will be enclosed in a small handheld device, so all components need to be as small as possible. The device will also include 2 small lasers to help align the device.
I’ve got the arduino sketch working how I need it to on an arduino uno using usb connection and a 9v battery powering a small hobby motor, but I’m having a hard time figuring out how to best provide portable power to the project. Ideally, the device will be run off batteries, but if needed, a plugin adapter could be used. So, my questions are:
Is it possible to run all of these components using a 9v or 2 AA batteries, and if so, how?
Could someone help me pick out a motor that would work for this project? (i.e. low power, small, slow, inexpensive, but able to turn a spool)
Any recommendations on inexpensive laser diodes that will work with my power requirements? They don’t need to be very powerful.
Is there a way to cut the size of the arduino, since I’m only using a few pins? Maybe using the mini or nano?
I’m new to the arduino and electronics world, so any help would be greatly appreciated.
Thanks in advance!