Digital pathfinding

jlowen — Sat, 01 Dec 2007 09:35:49 -0800

Is it possible to take a Digital Elevation Model of my favorite wilderness area and using OS X run some slope calculations in order to find new hike-able paths though an otherwise treacherous terrain? I did a somewhat similar analysis back in my PC days, but have not played with OS X options. Basically I want to take a DEM and tell the software to black out any part of the map that has a gradient of over X degrees... In other words, show me what areas are too steep to hike. I could then find the "safe zones" and translate them in to GPS paths in order to be able to see more of my beloved wilderness area. (Richland Creek Wilderness Area - Arkansas)

What software should I use on OS X to do this? (and how?)
Would the resulting analysis be reliable enough when I actually have boots on the ground?

How can I track myself with GPS and map my every move forever?

crazy finger — Wed, 29 Nov 2006 19:21:57 -0800

How can I best track my every move with GPS and then map it for a website and my personal use? I am a micromanager/microanalyst and I want to use a GPS all the time to track my movements and keep track of where I go and how often I go there. I don't have a tremendously huge budget AND I KNOW NEXT TO NOTHING ABOUT GPS.

Here is my best idea so far: Use a Laptop with a USB GPS like the one that comes with MS Streets and Maps to track my movements by vehicle - the bonus is that I will also have a relatively cheap (~$100) auto navigation system from this. Then, for non-auto travel, I will use a relatively cheaper handheld GPS that can track me while I'm hiking, boating, walking, etc... I can then upload that data and combine it with the vehicle data in some program that does TOPO maps of the entire USA.

I will be traveling a LOT this year, lots of stuff on backroads, dirt roads, hiking trails, canoe trails, bush-whacking, etc... and I want to track every bit of it to put together on a TOPO map of the entire country (since I will be in over 20 states). Ideally, I can also export that data into something like Google Maps and I could even have a setup where the tracks are shown with different intensities based upon amount of traffic - the path to X park will be thin, but the path to the local grocery store will be huge and wide.

So, the actual questions:

1. Is my plan above possible with consumer-level tech at an affordable price?

a. What handheld GPS devices would be best for this (especially in terms of data output for my uses)?

b. Is there good Topo software that covers the entire U.S.A. that doesn't cost a fortune?

c. Has anybody implemented this idea with Google Maps or anything else?

d. Is there software that does all this already out there?

e. Do you have a better plan than mine?

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Digital pathfinding

How can I track myself with GPS and map my every move forever?