Not enough power? Wires too thin?

Community General Discussions
1

Hi,

I have 4 lower power wild thumper motors that are rated at 6V 2.2A and I am powering each pair with 1 motor controller (l298n) that is quite cheap, powered by 2  6x AA (7.2V total, 2Ah) battery boxes in parallel to give 7.2V 4Ah per controller.

The robot that the motors are moving is quite heavy, but the wheel diameter is the same as the wheels used on the wild thumper.

When I make both controllers turn all motors forwards at full power, the robot hardly moves and even the tiniest bump stops it.The lights on the motor controllers also get very dim a sif there is not enough power (which is obviously the case).Is this because the battery box wires are too thin? They are very thin, and I understand that small wires cannot carry very much current. Should I use much thincker wires?

I would really like to continue this robot as I have put a lot of time and money into it. Does anyone have any suggestions/advice?

 

Thanks.

2

Thanks Guys!

Thanks for all the info!

I may have solved the problem though - I had a diode (connected the right way!) between the motor controllers and the batteries, and when I took it out after some testing with the volt/ammeter (I didn’t actually need it)  the motors had a lot more power. Now, when I set the motors to go forwards, they do, with a reasonable amount of torque. However, I think the whole set up is not powerful enough - when I set the motors to make the bot turn (left side forward and right side backward and vice versa) it can only just/not quite turn. The length/width of the bot is such that the motors at the front and the back are too far apart so there is not enough leverage to drag the grippy wheels round sideways. It looks like I might have to change the body or something. :frowning:

3

just for info

here is a good DC wires size calculator

 

http://www.solar-wind.co.uk/cable-sizing-DC-cables.html