Hi,
I am currently working on creating a automated fall detection device which requires an accelerometer, gyroscope, and bluetooth chip. I understand that I will need a protoshield to connect all the sensors to the board.
As of now, I am looking at the Arduino Uno and was wondering what kind of battery I should use. I require a battery that can last for atleast 24 hrs (if possible). I found a kit on online that offers a medium-cap lithium backpack or hi-cap to power either a duemilanove and/or arduino mega but was wondering if that same battery will be compatible with the UNO.
I have really no knowledge in electronics and would appreciate any feedback!
Thanks,
Persianeseguy
What you will need to do is add up all the power consumption of all your devices. Then with the mission duration, you can determine the capacity of the battery you need.
Each part should indicate how much current it consumes. Most of your items are likely to be in the single up to 100’s of milli (thousands) of an amp. Once you add them up, multiplty by the hours. You should now have something in milliAmp-hours. This is the absolute minimum capacity you need.
As an purely fictional example:
Thing A - 100ma
Thing B - 20ma
Thing C - 75 micro amps
Sum is 0.120075 amp. Times 24 hours is 2.8818 amp-hours. In this case I would look for a 5 amp-hour batery (2x margin).
fll-freak:
milli (thousands) of an amp.
Skye,
Did some “helpful” spelling “corrector” get the better of you here? :? Just to help the general readership:
1 milliampere = 1 mA = 0.001 A = one thousandth of an ampere.
1 kiloampere = 1 kA = 1000 A = one thousand amperes. (This is not a unit likely to be of use in hobbies, but it’s a standard unit and I do encounter it in my work with industrial machinery.)
Also:
1 microampere = 1 μA (for convenience, often typed 1 uA) = 0.000 001 A = one millionth of an ampere.
In the interest of clarity,
Eric
Thanks Eric. That sentence was poorly written on my part and might have had interesting concequences like buying a marine battery to power an LED for 5 minutes (or would it have been a hearing aid baterry to run a small city for a day?).
Skye,
You’re welcome!
Ah, but think of how much fun we could have with FLL rounds that lasted:
2.5 minutes * 10^6 = 41,667 hours = 1736 days = 4.75 years
~ the age range of the program. 
Eric
the Uno and Duemilanove are the same device just different generations. I have one of each and they are all but identical.