Batteries for my robot project

Other Hardware Motors, Mechanics, Power and CNC
1

Hi,

I need help in building my robot. I am using an arduino leonardo and an adafruit motor shield v2. I am also putting in an ultrasonic sensor. I am planning to make it small, so i am using the zumo chassis. That means it will function with the two micro metal gearmotors (also known as n20 gearmotors).

The zumo chassis has a place for putting 4 AA batteries. I want to recharge the batteries, and putting rechargeables means that i will only have 4.8v. But my project requires at least 6v. I need to power the two motors, the ultrasonic sensor, the arduino and the motor shield. So i will be needing a lot of current. At the same time, i need to fit the battery in the battery compartment of the zumo chassis.

Which battery should i use?
Should i use two li ion cells (thats about 7.4v and 2600mah)?
If i use alkalines, will it work?
Please help

2

Define "a lot of current" in amperes... Its useful to know both the running current and stall current for
the motors.

Sounds like you are expecting to power everything from one supply - bad news, rethink this, you
should strongly consider a separate motor supply.

With small motors and a beefy LiPo power pack you may get away with a single supply though.

3

Start with 4 AA cells and see how it goes. This is the cheap and easy option.

I have a similar palm sized 4WD robot (4 geared N20 motors) that runs off 4 AAA NiMh cells. In this one the Arduino is powered by a Pololu DC-DC converter off these cells, this provides 5V DC even though the battery voltage may be above or below this. It runs for about 1 hour so the average current is quite low (<1 Amp total).