Odometer to track distance traveled

[Cmdr Riker]

Hey guys, I want to find someway to rig up a gps or something on my scx10ii to track how many kms i've driven it. Not really sure where to start with it so any leads would be helpful. There is no particular reason for it, I just thought it would be a cool idea to track how far it's driven

[M1tch]

I think you can get gps receivers which you could connect wirelessly to a mobile phone and track that way. I used to have TomTom wireless receiver which owrked that way. Might be other brands that do the same.

[mewalsh100]

Garmin makes any number of small GPS units for treking and mountain biking. I have one for MTB that connects to my iPhone via bluetooth and the Garmin app. It’s about 3”L x 1.5”W x 3/4”D. You could probably go even smaller than that though as you won’t need or be using the onscreen functions while it’s stowed on your rig.

[Cmdr Riker]

Thanks guys that gives me a good start I'll look into Garmin stuff and post back with results!

[mewalsh100]

Originally Posted by Cmdr Riker

Thanks guys that gives me a good start I'll look into Garmin stuff and post back with results!

This is the unit I use for MTB:

https://buy.garmin.com/en-US/US/p/623539

The pic they post in this link appears to be actual size, so that should give you a better idea of dimensions. It's a bit pricey if your only intended usage is for your rig. But, if you cycle, hike, camp, etc it could come in handy for you in that regard as well. My favorite feature, particularly when I'm riding a new, unfamiliar trail is the "back to start" feature. If you end up hopelessly turned around, you can simply activate this mode and it will "bread-crumb" you back to where you began. It has helped me numerous times, and literally saved me a real cold night in the woods on one occasion!

[youngblood]

I feel like GPS isn't accurate enough for these tiny trucks unless you're doing G6 style driving/racing. You could make a ton of tight turns and stuff and the GPS wouldn't even pick it up. I'd like an odometer too, but it needs to be a physical revolution counter on the actual wheel.

[JatoTheRipper]

An old cellphone with an app would do it, but, again, it's your guess as to how accurate it is going to be.

[mewalsh100]

Originally Posted by youngblood

I feel like GPS isn't accurate enough for these tiny trucks unless you're doing G6 style driving/racing. You could make a ton of tight turns and stuff and the GPS wouldn't even pick it up. I'd like an odometer too, but it needs to be a physical revolution counter on the actual wheel.

I disagree. There are 2 settings in the Garmin that go to the rate at which it grabs data to plot. The "realtime" setting is extremely accurate. (uses more battery, but plenty for a 6+ hour ride) Some of the single track MTB trails we ride are damn near as tight as any scaler / G6 course i've seen. I've always ended up with an extremely accurate plotting / map rendering using the realtime mode when viewing in satellite mode.

[OSRC]

If you do trail runs, a walking app that keeps track of how far you walked will work as a good approximation. I used Map My Walk, found it pretty accurate.

[mewalsh100]

Originally Posted by JatoTheRipper

An old cellphone with an app would do it, but, again, it's your guess as to how accurate it is going to be.

My experience riding trails and having used both cell phone apps and GPS to track things like mileage, rate, moving time, etc are this:

1.) cell phone can be good if you're in an area where you have a good, strong signal for the entire route. When you don't, most of the apps make assumptions and approximations based on prior data captured to "fill in the blanks". So, in most instances for crawling/trailing, a cell phone with an app would probably be more than sufficient.

2.) GPS will lock on to a min of 3 satellites to even begin functioning, and will grab many more as available. So, if you plan to go camping somewhere or run the rig in a sparsely populated area with little to no cell signal, it's obviously the only game going. Also, even where there is cell coverage available, I have found GPS to be far more accurate. I've run the GPS and Cell Phone App(s) simultaneously to check consistency and accuracy. The GPS is always within low meters if not feet of accuracy. The phone apps are at best a good estimate over say a 10-15 mile trail.

[youngblood]

Originally Posted by mewalsh100

I disagree. There are 2 settings in the Garmin that go to the rate at which it grabs data to plot. The "realtime" setting is extremely accurate. (uses more battery, but plenty for a 6+ hour ride) Some of the single track MTB trails we ride are damn near as tight as any scaler / G6 course i've seen. I've always ended up with an extremely accurate plotting / map rendering using the realtime mode when viewing in satellite mode.

On some of our trail rides we stop and spend 20 minutes on a single obstacle that's only in a 6 foot area. You cant tell me a GPS unit is going to pick that up. Not to mention a GPS could never know wheel spinning mileage which depending how you drive could be a lot.

I've used the walking tracker app on my phone before and if you zoom in on your path it doesn't seem all that accurate.

[mewalsh100]

Originally Posted by youngblood

On some of our trail rides we stop and spend 20 minutes on a single obstacle that's only in a 6 foot area. You cant tell me a GPS unit is going to pick that up. Not to mention a GPS could never know wheel spinning mileage which depending how you drive could be a lot.

I've used the walking tracker app on my phone before and if you zoom in on your path it doesn't seem all that accurate.

No, I definitely AGREE that if you stop and "session" a certain area for a while, it's going to be tough to capture extremely accurate data. But, in my experience, I'd say you have a better chance of doing so with a GPS than a Phone App. Like I said above, all the phone apps I've tried use logarithms to make approximations where they can't gather data. So, it's kind of a best guess scenario. GPS on the other hand, will always have a signal to capture data. The more satellites it has bound to it, the more accurate it will be. And, with the features like sample rate selected to the highest available rate, it is still going to be your best bet in terms of overall accuracy.

Below is a screen grab from my Garmin app. You can see that we had some areas where we went back n forth or "sessioned" in a relatively small area that it captures with a pretty good degree of accuracy. I don't think anything is going to be 100%, but I'd definitely give the nod to GPS. That said, they're fairly expensive and not something I would consider if all I were going to do with it is track tiny truck mileage.

[M1tch]

As a thought. How about a GPS watch? They are fairly compact. It depends how much you want to spend. A basic unit would be more compact and easier to fit if you can remove the wriststrap. As for accuracy GPS would be best, but only within 1 metre (that's about as good as it gets I believe).

Working off wheel turns or measuring a shaft rotation would be inaccurate if you get any wheelspin. The old magnetic speedo/mileage on cycles are inaccurate as they dont allow for the diameter of a tyre when loaded.

[Stollenritter]

I would opt for a classic bike odometer like the sigma BC series:
https://www.sigmasport.com/en/produk...ed/wired/bc716

Low weight and low battery drain are pros, while minimum tire size (circumfence) could be an issue. Maybe someone can fix this?

[mewalsh100]

Originally Posted by Stollenritter

I would opt for a classic bike odometer like the sigma BC series:
https://www.sigmasport.com/en/produk...ed/wired/bc716

Low weight and low battery drain are pros, while minimum tire size (circumfence) could be an issue. Maybe someone can fix this?

I've considered this as well. The problem I see is that you have to run a magnetic pick-up on the wheel that comes around and ticks off revolutions to a sensor. Diameter can be custom programmed in to most of these, but I'm not sure you could get down to a 1.9 or even 2.2 sized crawler tire. And, I can't picture any way to mount the pick-up and sensor on a crawler wheel that would not interfere with rotation and articulation.

[Stollenritter]

It is just a small magnet and a reed-switch. Should be small enough after de-casing for fitment at the rear axle. Minimum tire size is the dealbreaker: "set wheel circumference: 1253 - 2253" in millimetres, I assume.

[mewalsh100]

I could see possibly getting the magnet fitted to one of the rear wheels. Although in terms of scale for a crawler, it'snot that small. The pick-up is another story. I've used these units on my bicycles in the past. The pick-up, or sensor, for lack of a better way to say it, is fairly large probe. They're generally an inch or so long to account for "sweep" of the wheel and where the magnet gets fitted to the cross lacing of the spokes of any given diameter of wheel. I just can't see where you could locate and mount the pick-up where it wouldn't become obtrusive. (circled in red)

[M1tch]

Yeah, the size is big for what's needed I think. Also calibration as it maybe too small a wheel diameter.

[mewalsh100]

I may pull one of my old units off the shelf and play with the wheel size formulas to see if it's even possible to get down to the 1.9 or 2.2 size. So even outside of the practical issues with mounting up this sort of set up, if it can't be properly calibrated, the whole point is mute.

[gottorque]

I use Strava on my Android for my ultra training and mileage recording but that is more for keeping track of my running than the exact car mileage. Even in areas with zero phone service it works just fine on GPS only and tracks your route fairly accurately in my experience.

Instead of on the wheel, could you not mount a bike computer and have it read off the driveshaft. Calculating driveshaft revs per mile of a 10.2 with 4.75 tire (assuming zero wheel spin) is 15,922 revolutions if I did the math right. Might be a little more out of the way there.