Jump to content
corncobs

Trip elevation mapping

Recommended Posts

Wouldn't you have the same time base? When I did extract some of my data into Excel I normalized everything to 1. It should be possible to do the same with the MPG results when the ski track is started as soon you start the car.

Ya, I think it would be pretty easy to normalize everything, but first I have to get one of those OBD dongles that will transmit engine telemetry to my smartphone. One thing I do want to also do is record a number of Ski Track runs to and from work so that I can average out the elevation data. Given GPS data can bounce around, it will be important to get enough data samples to average out this data and smooth the route.

Share this post


Link to post
Share on other sites

A comment to the above speed profile. It's seems to not pick up stops at stop signs very well. This route has a fair number of stop signs. The three stops shown above were three red lights. None of the stop signs show our speed reaching 0 MPH. Each of the downward spikes from about 25-30 MPH down to 10 MPH is actually a stop sign.

That's due to the frequency at which your smartphone updates its GPS location.

Share this post


Link to post
Share on other sites

How frequent does yours update do you know? I noticed that your profile look a lot smoother. I have an iPhone 4S and it's updating the GPS every second based on the data readout I did with Excel.

Just because the app is recording data every second doesn't mean the smartphone is actually updating GPS coordinates that often. I don't know how often my phone updates, but it also misses complete stops in my elevation profiles. Also, depending on where your phone is placed, it might not be getting a full range of GPS satellites causing it not to get as good of a position lock as it might otherwise.

 

my profile looks smooth because:

  • I'm driving on cruise control in eco mode and typically don't have traffic that is causing the car to adjust its speed;
  • GPS signal quality, I lock my phone into a windshield mounted holder so that its GPS antenna doesn't get too much interference;
  • I regularly update my phone's AGPS data cache;
  • my commute is fairly long so the graph gets compressed to the point you don't see small fluctuation in speed/elevation.

Most phones can't be manually forced to update their AGPS data cache, however, my phone is rooted and I have an app called "GPS Test Plus" that will force an AGPS update on rooted phones.

Share this post


Link to post
Share on other sites

Hybridbear, I'm not sure I'd post a map of my exact start and end points if either were my home or work locations. You never know who is lurking in forums like this. It is almost as bad as announcing that one is going on vacation on one's Facebook profile.

Share this post


Link to post
Share on other sites

Here's the SkiTrack for my trip home this morning from my camping trip near Fryburg Maine. The EXIF data of the photo of me and my FFH contains the exact GPS coordinates of our campsite on the Saco River. The Saco River also flows through Saco where I live so this trip was a net loss of a couple hundred feet in elevation. Max speed limit was 55mph. I didn't run cruise control this time, because I wanted to try and maximize EV mode time. I got 56.9 mpg for the trip.

 

SkiTrack_2013-08-13.png

 

gallery_12057_318_28069.jpg

Share this post


Link to post
Share on other sites

I've had one time imported the route elevations in Google earth from my tracks app. and you can overlay the elevation to the point on route you pick. it's pretty cool to try that for the most common routes. check it out.

Share this post


Link to post
Share on other sites

remember that route elevation is one imp factor for mpg,but wind direction is another one that you may not directly account for or be able to control in order to improve your mpg.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...