I'm planning to do some DIY project, and I'd appreciate your help and advice in the matter.
So basically I'd like to build an automatic window shade system. It is a simple shade, that you can pull up/down and close/open the blades, but I'm only planning to use the latter. I'd like to use a phototransistor to measure the intensity of sunlight and close the blades in proportion by rotating the hanlde on the shade. Fortunately it doesn't need much torque to turn it, and I would check and adjust the blades once around every hour, so it won't take much power, however I'd like to make as self sufficient as possible, so my idea to power it with a battery source (preferably a phone battery or notebook battery), and recharge it with a small solar panel. So I need to find a solution to rotate the handle with a low-power actuator.
This is where my question lays. I'm not sure what kind of motor should I use for this:
1) Step motor:
would be ideal, because I don't need high RPM
no need for additional encoder to properly control tha angle of the blades
few extra mechanical parts
more complex driver
more roboust power supply
2) DC motor:
lower voltage and current levels? (actually i'm not so sure about this :D)
needs additional encoder
needs a complex gearbox to achiev proper torque and RPM, which can be a pain in the @ss to make...
So this is my problem, what do you think?