Battery selection for my project

I am making a project with following components-

  1. Arduino Uno x 1
  2. TowerPro MG996 Servo x 4
  3. Ultrasonic Sensors x 2

The Project Idea is very simple.
The Ultrasonic sensors will detect a object and then the Servos will lift the wall.
There the two walls for 1.5kg each. From the servos the 2 servos will lift a wall.

I am having problem in selection of battery.
Can anyone tell me of what Voltage and mah battery do I use for my Project.
Thanks!

How long do you want it to run before depleting the battery? The "h" in mAh stands for "hours".

hmm 5-6 hours

How many lift operations during that tme?
Read the datasheet for servo current at that load and multiply by time. That's the energy needed.

Have you looked at the electrical specifications of the devices you listed? Please find them, and post them here if you don't understand them.

What is your usage pattern? For example, are the servos always running? No? What percentage of the time, then?

Do you mean MG996R, with stall current 2.5A? If so, best to use a heavy duty rechargeable battery pack (e.g. RC racing type), 4.8 to 6V, capable of 10 Ampere discharge.

Be sure to solder servo power connections, or use quality connectors with a servo power distribution PCB.

Its a project based on a bridge. If a car comes at the edge of the barriers of bridge the wall lifts and thats it

Ok,
Means I should use a battery of 6V, 10000mAh

You are making a model for testing the concept?

yes

One of these would give about 2 hours of operation

If it was my project, I would take the easy approach;

Measure the current that flows when lifting the wall.

Decide how often you want to lift the wall.

Do the sums.

Because friction in the mechanics of how the servos lift the wall can have a significat effect on the current used, I doubt very much you can 'calculate' or even guess at the curent used, and hence the batery capacity needed, you just need to do measurments.

Got a multimeter ?

Get the project working using mains supply. When the project is ready You can measure currents, using the specified frequency of actions, and calculate the capacity of the battery.
Hopefully the installation will sit idle for all, or nearly all, of the time.

Hmm, ok
Thanks :wink:

I want to control TowerPro MG996R servo motor with arduino. I have the code also. but i dont have the battery.
The Specifications of TowerPro MG996R Servo Motor
Operating voltage: 4.8~ 6.6v
Current draw at idle 10mA
No load operating current draw 170mA
Stall current draw 1400mA

can anyone help for selection of battery
Please tell me the specific voltage and mah I need for my project

How long do you want to run the project on battery?
What is the duty cycle?

10 hours

Well at 1400mA how long is the circuit supposed to run?

A 1400mAh lipo would run for about an hour.

A 2800mAh lipo would run about 2 hours.

A 14000mAh lipo would run for about 10 hours.

can you tell me for 10 hours

thanks