I'm making a model of the mars Curiosity rover. I'm using lots of servo's (6 modified ones for driving, 4 for turning, and a few more of various sizes for the arm and camera movement).
I'm planning on using a typical 2S2P LiPo battery (four cells, 2 of which are in series and two of which are in parallel), which should output 7.4V (I chose 7.4V because it's close to the voltage I need).
The 7.4V should be fine for the arduino (I'm going to use a Mega because of the large number of servo's).
The large servo's I'm planning on using (the 6 modified ones for driving and 4 for turning) should run at 6V and ~400mA each. 7.4V is too much for them.
Some of the other tiny servo's for the arm will go to as low as 4V.
I have no idea how voltage is regulated. With my understanding, a battery provides a constant voltage and as much current as is needed (with limits, of course).
What would be the best way for me to step down the voltage to 6V (at least 5A) and other voltages at much lower currents?
It might be as simple as using a resistor, I really don't know.