So I will get straight to the point. I wanted to get ambitious with my robot project while trying to keep the budget minimum. I have browsed through several posts regarding power sources and servos, and most of them keep me juggling my choices.
Choice for servos:
I noticed how convenient MG996R is for my intended purpose, but I also realise that it adds to weight of the robot (18 motors is around 990 grams). Hence I'd need more power for these bad boys. Another option I observed was using MG90 micro servos, but the overal torque of these motors are far too small compared to MG996R. I am really confused as to whether I should choose MG90 for light-weightedness (240 grams for motors) or should I go for MG996R for higher torque while getting higher weight.
I don't know which among these two are more accurate either. Would it be mg90? or MG996R? I currently have sg90 from my previous project of 4-legged robot, but I recall how poorly accurate they were and also they were easy to break due to plastic gears.
Since I am making a hexapod, I wish to have proper accuracy, but once again I can't spend 30 dollars for each hitech servos with high torque, I wish to keep the budget low as possible. MG996R itself is quite high for my budget.
Choice for Power:
I also wish to understand how to choose my power source. One group of people suggest 18650 power source, but they'd provide 3.7V alone, and 7.4V if put in series. One post mentioned if we were to use single cell, we'd need a boost convertor, and buck for the other case. I wish to know how do these choices effect overall current output.
Some suggest to get NiMH batteries as they are perfect at 6V for the servos, but I wonder about their total current discharge seeing as how the motors require at most 15A or 18A.
I wish to see some successful choices of the above components, or maybe better equivalent components. Some people say MG996R was a failure for these hexapod projects, and it scares me to take up this project for this reason. Help me get an insight as to how I can choose an ideal servo motor and the ideal power source with appropriate circuits that support the distribution of power.