# Thread: Mechanical Engineering. Motor Sizing

1. ## Mechanical Engineering. Motor Sizing

I am a freshman mechanical engineer and I do not believe that I have taken enough physics or statics to accomplish this task in a timely and correct manner. I am an intern at a government contracting company and am building a model of an AAV track system to test different coatings on. I need to know what size motor I will need to run this so I need to know how to do all of the calculations of torque and make sure it can run.
The track is 140" long and will weigh around 750 lbs. It runs on a sprocket that is 24 inches in diameter and is at a 28 degree angle from the single road wheel (also 24 inches in diameter) that will be touching the belt its running on. How would i account for all of the forces ( including a lot of friction from the gravel its running on)? I am guessing that the sprocket and road wheel each weigh around 100 lbs. Sorry if this is laid out poorly. Let me know if I can clarify anything.

2. This project may be clear in your mind, but you have not even come close to describing what you are requesting assistance with.
What does it matter if the track weighs 750-lb?
"It runs on a sprocket..." What is "it?"
How can "it" run on a sprocket? A chain can run on a sprocket.
Where is the belt? What is it's purpose?
If it is a "road wheel" then how is it running on a belt?
28 degrees from what? Vertical? Horizontal? The angle of the bridge of my nose?
You need to post a drawing, sketch or a picture. So far, to this feeble old mind, none of what you have outlined makes any sense.

I fear for the future of Engineering. :O

Dave
Generally, I will not give you the answer to your question, but I *will* guide you into discovering how to solve this yourself.
Insanity: "doing the same thing over and over again and expecting different results." Albert Einstein

3. "I fear for the future of Engineering. :O"

What about English?

4. ## Motor Sizing

Come on Turner! The old boys have had a giggle, but they've also made some fair criticisms.

I'm sure there will be lessons in this for everyone - please stay with us and define your problem with a sketch or some more words. Eventually we'll have a diagram that shows a bunch of levers, and we'll work out a torque from it, I'm sure you can sketch it.

What you're doing CORRECTly is i) showing due respect for the problem and ii) seeking help. Hopefully the third thing you'll do correctly is hold your chin up, ignore some childish heckling from the gallery and close the problem out.

5. What's wrong with that Zeke? Alliteration illegal in some States?

http://en.wikipedia.org/wiki/Alliteration

Dave
Generally, I will not give you the answer to your question, but I will guide you into discovering how to solve this yourself.
Insanity: "doing the same thing over and over again and expecting different results." Albert Einstein

6. ...did I forget to mention patronising back-slapping?? Pink/Zeke you should have a look at yourselves. Maybe even go and google the word 'forum' - you might evolve into more constructive contributors.

Dave
Generally, I will not give you the answer to your question, but I *will* ridicule you into not asking any more.

7. Originally Posted by Bruiser
...did I forget to mention patronising back-slapping?? Pink/Zeke you should have a look at yourselves. Maybe even go and google the word 'forum' - you might evolve into more constructive contributors.

Dave
Generally, I will not give you the answer to your question, but I *will* ridicule you into not asking any more.
According to the logs, turner91 has not been back since posting the original question - we have a "drive-by question poster" so far..

I think I have read every post ever made on EE and……I like clever humor.

8. Originally Posted by Kelly Bramble
I think I have read every post ever made on EE and……I like clever humor.
Me too, so where is it?

@Bruiser: {sigh} Maybe Google 'chaf' - you might evolve into a more laid-back contributor.

v.tr.
To make fun of in a good-natured way; tease.
v.intr.
To engage in playful teasing. See synonyms at banter.
http://www.answers.com/topic/banter

Dave
Generally, I will guide you into discovering how to look at yourself.
Insanity: "doing the same thing over and over again and expecting different results." Albert Einstein

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•