OnlineConversion Forums Welcome to OnlineConversion.com Forums

Go Back   OnlineConversion Forums > Main Forums > Convert and Calculate

Convert and Calculate Post any conversion related questions and discussions here. If you're having trouble converting something, this is where you should post.
* Guest Posting is allowed.

Reply
 
Thread Tools Display Modes
  #1  
Old 12-05-2008, 06:16 AM
lym
Guest
 
Posts: n/a
Default how do I convert revolutions to miles?

Hi can anyone help me with this. I bought a elliptical and the distance is in revolutions. I need to know how many revolutions equal a mile. I was told it was 300-350 revolutions to a mile. Is this correct?

Last edited by lym; 12-05-2008 at 06:17 AM. Reason: notification
Reply With Quote
  #2  
Old 12-05-2008, 06:37 PM
Robert Fogt's Avatar
Robert Fogt Robert Fogt is offline
Administrator
The Golden Calculator Award Over 1000 Posts
 
Join Date: Dec 2005
Location: Seattle, WA
Posts: 3,467
Rep Power: 13
Robert Fogt is on a distinguished road
Default Re: how do I convert revolutions to miles?

It probably differs between manufacturers, and you'd have to contact them for that information.

1 mile = 5280 feet

If 1 revolution was 2 steps (ie right foot then left foot) and your step is 2 foot long, then:

5280 feet / 2 feet = 2640 steps / 2 = 1320 revolutions

If you can measure how long each stride is, and determine for sure how many steps/strides in each revolution, then you could calculate fairly accurately.

That wouldnt work for exercise bikes, just elliptical machines.
Reply With Quote
  #3  
Old 12-06-2008, 04:50 AM
lym
Guest
 
Posts: n/a
Default Re: how do I convert revolutions to miles?

Thanks for the help so you think 1 mile is 1320 revolutions? Wow that is different from what Welso said they claimed 300-350 revolutions = 1 mile. Here is more info I have a Weslo Momentum 620 the stride is '13 and when I use it once I go round once right and left foot the revolution changes to 1.

Quote:
Originally Posted by Robert Fogt
It probably differs between manufacturers, and you'd have to contact them for that information.

1 mile = 5280 feet

If 1 revolution was 2 steps (ie right foot then left foot) and your step is 2 foot long, then:

5280 feet / 2 feet = 2640 steps / 2 = 1320 revolutions

If you can measure how long each stride is, and determine for sure how many steps/strides in each revolution, then you could calculate fairly accurately.

That wouldnt work for exercise bikes, just elliptical machines.
Reply With Quote
  #4  
Old 12-06-2008, 07:00 AM
JohnS JohnS is offline
Moderator
Long Time Member The Golden Calculator Award Over 5000 Posts
 
Join Date: Dec 2007
Location: SE Michigan, USA
Posts: 9,536
Rep Power: 19
JohnS will become famous soon enough
Default Re: how do I convert revolutions to miles?

Lym,

You have to analyze the horizontal motion of the pedal. In one revolution, it returns to where it was (it corresponds to a left stride and a right stride). Your machine's stride is specified as 13" but you could measure it. Place a newspaper under machine (to mark on) rotate wheel slowly, and place a mark on paper vertically below the forward and rearward points of travel ot the toe tip (or any feature of the pedal) and measure the stride.

A mile is 5280 feet or 63360 inches. There are 2 strides in a revolution, so divide 31680 inches by the stride 13 inch/stride. I think your machine is 2437 rev per mile. Other machines have longer strides, 18" which would be 1760 rev per mile.

In normal walking, most people have a stride (one sided) of 30" or a pace (left and right) of 60". I'm tall, have a natural stride of 36" so any of these machines would force me to take "baby steps."

The difference between this figure and the 300 rev/mile claim may be exertion. The elliptical may require you to overcome resistance over more of the range of motion or overcome greater resistance than normal walking would require. If they have data to back it up, this "work equivalence" point of view would also have merit. We have directly related the horizontal movement to walking distance, but ignored effort.
Reply With Quote
  #5  
Old 12-06-2008, 07:02 AM
Robert Fogt's Avatar
Robert Fogt Robert Fogt is offline
Administrator
The Golden Calculator Award Over 1000 Posts
 
Join Date: Dec 2005
Location: Seattle, WA
Posts: 3,467
Rep Power: 13
Robert Fogt is on a distinguished road
Default Re: how do I convert revolutions to miles?

I would go by what the manufacture claims.

But if I had to figure it out:

5280 feet / 12 = 63360 inches
63360 inches / (13 inches * 2) = 2436.92 revolutions

13 inches * 2 = 26 inches * 300 revolutions = 7800 inches = 650 feet = 0.12 miles

But 13 inches seems like a very very short stride, like baby steps. That probably is a typo.
Reply With Quote
  #6  
Old 12-06-2008, 07:03 AM
Robert Fogt's Avatar
Robert Fogt Robert Fogt is offline
Administrator
The Golden Calculator Award Over 1000 Posts
 
Join Date: Dec 2005
Location: Seattle, WA
Posts: 3,467
Rep Power: 13
Robert Fogt is on a distinguished road
Default Re: how do I convert revolutions to miles?

Wow I type too slow.
Reply With Quote
  #7  
Old 12-06-2008, 07:12 AM
JohnS JohnS is offline
Moderator
Long Time Member The Golden Calculator Award Over 5000 Posts
 
Join Date: Dec 2007
Location: SE Michigan, USA
Posts: 9,536
Rep Power: 19
JohnS will become famous soon enough
Default Re: how do I convert revolutions to miles?

Great minds think alike.

The 13" claim troubled me, so I looked at several machines. 13", 15", and 18" all seem common. It is limited by the diameter of the wheel (at the point the linkage is attached). The pictures would appear to bear out the claim (as well as I can judge. All are basically four-bar linkages which convert rotary and reciprocating motion.

For me, they are baby steps and I'm sticking to my NordicTrack cross country sky machine.
Reply With Quote
  #8  
Old 12-06-2008, 08:28 AM
lym
Guest
 
Posts: n/a
Default Re: how do I convert revolutions to miles?

Now I am really confused. Seems like the number keeps going up.
Quote:
Originally Posted by JohnS
Lym,

You have to analyze the horizontal motion of the pedal. In one revolution, it returns to where it was (it corresponds to a left stride and a right stride). Your machine's stride is specified as 13" but you could measure it. Place a newspaper under machine (to mark on) rotate wheel slowly, and place a mark on paper vertically below the forward and rearward points of travel ot the toe tip (or any feature of the pedal) and measure the stride.

A mile is 5280 feet or 63360 inches. There are 2 strides in a revolution, so divide 31680 inches by the stride 13 inch/stride. I think your machine is 2437 rev per mile. Other machines have longer strides, 18" which would be 1760 rev per mile.

In normal walking, most people have a stride (one sided) of 30" or a pace (left and right) of 60". I'm tall, have a natural stride of 36" so any of these machines would force me to take "baby steps."

The difference between this figure and the 300 rev/mile claim may be exertion. The elliptical may require you to overcome resistance over more of the range of motion or overcome greater resistance than normal walking would require. If they have data to back it up, this "work equivalence" point of view would also have merit. We have directly related the horizontal movement to walking distance, but ignored effort.
Reply With Quote
  #9  
Old 09-12-2009, 09:26 AM
Fletch
Guest
 
Posts: n/a
Default Re: how do I convert revolutions to miles?

Well, quite honestly there is not a direct conversion from revolutions to miles. And that's why most manufacturers give you distance in revolutions instead of distance in miles. It really depends on whether you want "actual" miles or "work equivalent" miles.

Most manufacturers will give you the stride length in the owner's manual. For example, the stride length on my elliptical is 18". And, 2 strides is equal to one revolution. If you don't have the owner's manual you can simply take a tape measure and determine how far one side of the elliptical travels from its furthest point of forward motion to its furthest point of rearward motion. Mulitply that by 2 and you have the total distance travelled for one revolution. This is the "actual" distance travelled.

The reason that most manufacturers give you revolutions is that the distance the wheel travels through one revolution is typically further than the stride distance. For example, if the wheel on your elliptical has a 20" diameter (typical for many Nordic Trac ellipticals), the wheel travels the circumference of the wheel through one revolution or approximately 62.83 inches (5.236 feet).

Circumference = 20" (pi) or 20" (3.14159) = 62.83 inches (divide by 12 inches/foot and you get 5.236 feet)

Realize that through the entire range of motion of the wheel on an elliptical part of the motion translates to up and down motion and not forward motion. However, you still have to expend energy in the form of work to move the wheel through that entire range of motion. So, you've actually done more work in one revolution than just the actual distance travelled by your stride length.

Using the example of my own elliptical, while the "actual" distance travelled for one revolution is 36 inches or 3 feet, you have in fact done work equivalent to travelling 5.236 feet by moving the wheel through one revolution (that's why I refered to it as "work equivalent" miles). Since there are 5280 feet in one mile, I would have to do 1760 revolutions to travel the actual distance of one mile. However, you do the equivalent work of walking one mile in 1008 revolutions (1008 revolutions x 5.236 feet/revolution = 5278 feet). Hope this isn't too confusing.

So, while converting revolutions to miles is not like comparing apples to oranges, it is akin to comparing MacIntosh apples to Red Delicious apples.

BTW, I can tell you from experience that I expend more energy putting 2.5 "work equivalent" miles on my elliptical than I do walking 2.5 actual miles through my very hilly neighborhood.

Hope this helps.

Last edited by Fletch; 09-12-2009 at 09:37 AM.
Reply With Quote
  #10  
Old 11-22-2009, 05:52 PM
Unregistered
Guest
 
Posts: n/a
Default Re: how do I convert revolutions to miles?

Quote:
Originally Posted by Fletch View Post
Well, quite honestly there is not a direct conversion from revolutions to miles. And that's why most manufacturers give you distance in revolutions instead of distance in miles. It really depends on whether you want "actual" miles or "work equivalent" miles.

Most manufacturers will give you the stride length in the owner's manual. For example, the stride length on my elliptical is 18". And, 2 strides is equal to one revolution. If you don't have the owner's manual you can simply take a tape measure and determine how far one side of the elliptical travels from its furthest point of forward motion to its furthest point of rearward motion. Mulitply that by 2 and you have the total distance travelled for one revolution. This is the "actual" distance travelled.

The reason that most manufacturers give you revolutions is that the distance the wheel travels through one revolution is typically further than the stride distance. For example, if the wheel on your elliptical has a 20" diameter (typical for many Nordic Trac ellipticals), the wheel travels the circumference of the wheel through one revolution or approximately 62.83 inches (5.236 feet).

Circumference = 20" (pi) or 20" (3.14159) = 62.83 inches (divide by 12 inches/foot and you get 5.236 feet)

Realize that through the entire range of motion of the wheel on an elliptical part of the motion translates to up and down motion and not forward motion. However, you still have to expend energy in the form of work to move the wheel through that entire range of motion. So, you've actually done more work in one revolution than just the actual distance travelled by your stride length.

Using the example of my own elliptical, while the "actual" distance travelled for one revolution is 36 inches or 3 feet, you have in fact done work equivalent to travelling 5.236 feet by moving the wheel through one revolution (that's why I refered to it as "work equivalent" miles). Since there are 5280 feet in one mile, I would have to do 1760 revolutions to travel the actual distance of one mile. However, you do the equivalent work of walking one mile in 1008 revolutions (1008 revolutions x 5.236 feet/revolution = 5278 feet). Hope this isn't too confusing.

So, while converting revolutions to miles is not like comparing apples to oranges, it is akin to comparing MacIntosh apples to Red Delicious apples.

BTW, I can tell you from experience that I expend more energy putting 2.5 "work equivalent" miles on my elliptical than I do walking 2.5 actual miles through my very hilly neighborhood.

Hope this helps.
Fletch, love your explanation. Tell me more, teacher. My elliptical (ProForm Quick Burn Spacesaver) also has an 18" stride, the wheel is not visible in the plastic housing, and I have 10 levels of difficulty (resistance). Assuming my wheel is the same as yours, any chance you know how to calculate the different settings into the equation? I just finished a jaunt with these stats: Level 3, 31 minutes, Distance 1896, Calories burned 465, carbs burned 81. Thanks! Robin
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -8. The time now is 08:49 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 1997-2005, 2007, OnlineConversion.com