Hi, I need a solution with the power for my project.
I made a robot that uses 12 servos (all TowerPro SG90. controlled by a Nano. Everything works fine when I use a PC PSU 5V/21A external power. Now I need to use a battery as the external power source. I had tried a 9V 1.25A NiHM battery (It was stepped down to 5V with a 7805 IC.) The battery simply doesn't have enough power to drive all servos. I thought of parallel connect two same batteries to beef up the current, the problem is that will increase the weight and size of the robot. I am stuck at this point, any suggestions will be greatly appreciated.
If you have 12 servos running at once you may need as much as 12A to drive them. Perhaps if you put 8 of those 9V batteries in parallel... If you want regulated 5V you will need a much heftier regulator.
9V batteries have extremely poor volume/performance ratio. I think you will be better of with a single cell LIPO and a boost regulator or maybe 2 LIPO's and a step down regulator. Also, review your code so that only one servo changes its position at any moment.
nilton61:
9V batteries have extremely poor volume/performance ratio. I think you will be better of with a single cell LIPO and a boost regulator or maybe 2 LIPO's and a step down regulator. Also, review your code so that only one servo changes its position at any moment.
Please bear in mind that this is not just one of the 9V battery you get from CVS or places like that, it's a 9.6V 1250mA heavy duty battery. And yes, all 12 servos for this robot has to run in sequence. The only work around I can think of is to use the Nano to turn off the servos that are not in use within that sequence.