# DC Motor Selection

I'm trying to build a remote control submarine and I need some help in selecting an appropriate DC motor. I'm not a mechanical engineer and I don't really know anything about fluids or motor selection. The shape of the submarine is cylindrical with about a 3 inch diameter. I want to be able to go at least 1 m/s. I found this website: #-Link-Snipped-# that seemed somewhat helpful. They first calculate the power of the motor that they need based on the motor's rotational speed and torque. The problem is I don't know how much torque I need for the motor or it's rotational speed. I tried using this equation that I found on wikipedia: F= -1\2p* v^2*A*C to give me the drag force of the submarine and I figured the thrust of the motor would need to equal that. I still don't know how that would relate to the torque of the motor though or how fast the motor would need to spin. As far as the voltage source goes, I was thinking of connected two 7.2 volt batteries in series to give me 14.4 V. Thanks for any insight that someone could offer me.

## Replies

You are reading an archived discussion.

## New Member salutes CE

me at 440 W after registering for CE

## Applying to an MBA program in the USA?

Anyone here have tips on the steps in getting an MBA degree from a US institution. In particular, I'm looking for: a) MBA programs that have historically catered to foreign...

## can google search be 'extended' to desktop search

:smile: i search a document on google and google returns.. what if i already have a file in some of my lappy's drive which meets the search criteria??? is this...

## Distance learning or correspondence MBA

Can anybody tell me some good colleges for Distance learning or correspondence MBA. Is there any difference in the two? I have 3.5 yrs of experience in IT and its...

## How does information data travel through Internet?

i heard that information through internet travels through cables under sea. is it true? That means there is under sea cable connection between all the countries....