As the appointed route developer for the upcoming Get Together in Eureka Springs, I'm trying hard to understand what makes our Boom Boxes work (called BB hereafter) and specifically, how and why our navigation system does what it does.
Up until now, I've questioned whether we will ever fully understand how the BB nav works, and sometimes I wonder if the nav portion will ever work the way we want it to.
Let's face it. It's easy to blame the Rushmore project and then give up trying to get the darn nav system to do what we want, but it's tougher to actually sit down, do the research on-line, and then troubleshoot and war game it to figure the infernal thing out.
I have a theory about our BB's and want to sound it off on you guys. My theory concerns the topics of "avoidances" and "preferences" in the nav system, and then the difference between the two types of routes we will use with the system.The first type of route is what I would call "navigating on the fly" (NOF for short). This is where you're out running around on the bike, and then decide you want to go to the nearest Red Lobster or Lowe's, or whatever, so you let the nav system search for the location, and then route it for you.
The second type of route is one you define by means of some type of GPS software, where you create the route from scratch and then import it into your BB. I'll call that type a GPX route for short. Can you tell I have a military background with all these acronyms?
If you think about it, what's the difference between these two types of routes? The first is, with NOF navigating, you're letting the BB decide how to get you from point A to B, and the other main difference is the NOF has no user defined waypoints (WP's) in the route, only a starting and ending point.
Why is that important? Well, this is where my theory about the "avoidances" and "preferences" settings come into play, and here's what I'm thinking:
Since the NOF style route is BB designed and has only a starting and ending point, the BB is free to take you where it wants to in order to get you to that Red Lobster. And this (I think) is where "avoidances" and "preferences" have the majority of the effect on the route you take.
Think about it...if you import a GPX route, you are in effect telling the BB exactly where you want to go, and each turn that's involved, and this is all done with the WP's you've chosen.
But since the NOF route has no waypoints, then you you only get to define the type of roads you want to ride on to get to that Red Lobster by selecting maybe the "scenic" route, or the "fastest" route, or whatever preference you like best. And in the meantime, you can choose to avoid "interstates" or "toll roads" or whatever by the use of avoidances. My theory is that this is how you get to have any input at all into how a NOF type route is created.
Conversely, with a GPX route, you may have designated that you didn't want to go on a toll road (in the avoidances section), but when you devised the route, you decided had no choice in a certain area but to use a toll road, and so you input the WP's to do that, and it will do that then
in spite of your choice of avoidances. You could also choose not to go on a scenic road that is readily available to get to your GPX destination, but rather you want to take the fastest road along your route, and again, the system will follow your WP's instead of your choice of preferences.
So why does the darn BB continue to take us where we didn't choose to go with our GPX file? My theory here is that we; 1) didn't use enough WP's in developing our route; and/or 2) we didn't place enough of them in busy routes with lots of turns (like in a city), and/or 3) we didn't zoom in and check our exact placement of each WP well enough as we generated our route.
We can control #3 above by reviewing our route closely before saving it, but as far as #1 and 2 above go, how do we know we've used enough waypoints, or that we've placed them in the right spots?
I figure the only way to do that is by trial and error. Try adding more WP's to the complicated areas of your route, and see if it helps to "force" the BB into regurgitating your route exactly as you originally devised it. I think you'll find it will.
Look at the jpg below. The left side shows a basic route running through the city, with just enough waypoints that the route looks like a sure thing...right? But all of us know that by the time our BB imports it and we start to drive it, we could end up taking turns where we didn't want to or going on streets we didn't want to.
Now look at the right hand map. Notice I've placed WP's before and after each turn? My theory is that this "forces" the BB nav system to take a turn and stay on that street until you come to the next turn. After all, WP's are just latitude and longitude coordinates that the BB must take you through. Heck, I might even add an extra WP between WP's 3 & 4 or between 7 & 8 if I felt the straight stretches were too long...just to make sure that I stayed on that road all the way to the next turn.
Isn't this redundant and extra work? Yes, but I can tell you that this system works, whereas if I devise a GPX route that looks like the left hand map, I'll be going through Timbuktu to get where I want to go. And it takes very little time to add a few more WP's...certainly a lot less time and hassle than to head down the wrong street in a bad neighborhood all the while trying to figure how to get back on the route.
I welcome your comments on this or any other BB nav subject.
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Topic: BoomBox Navigation, GPX files, and my thoughts on creating routes... (Read 6736 times)