Use Pocket Rangefinder To Estimate Distances

[Ed Hansberry]

<a href="http://www.zedev.com/rangefinder.html">http://www.zedev.com/rangefinder.html</a><br /><br />"Pocket Rangefinder allows you to quickly and accurately measure the distance to far-away objects using only your Pocket PC." You use the image database, which is user customizable, to approximate the relative size of someone and Pocket Rangefinder will give you the estimated distance. It claims to be accurate within 5%.<br /><br /><img src="http://www.pocketpcthoughts.com/images/hansberry/2003/20030822-pocketrangefinder.jpg" /><br /><br />It works on all Pocket PC devices. There is a trial or you can buy it for $5.95.

[David Prahl]

This doesn't seem all that practical to me. When I think of using a range finder, I think golf, hunting, or surveying. Most of the targets you'd use in these activities would be of variable size (trees, buildings, golf flag, people).

Also, the PPC would have to be an exact distance from your eyes for it to work correctly. Do they include a string?

Has anyone tried this? I don't have a cradle here at work (or a racecar).

[Peter Foot]

This may work for object like cars where you already have a good idea of their size, but imagine seeing an aeroplane at great distance you might see

-\-

(like my ascii art?) But it could be anything from a radio controlled toy to a 747 which makes a huge difference to the actual distance, add to that atmospheric conditions...

[gorkon280]

This is a Neat Idea but it's hugely inaccurate. This would just be ball park. It would be nice if the pocket pc OEM's would make a IR transciever that first the transmit side was strong enough and on the receive side was sensative enough to detect the reflected beam back, then you'd be able to creat a fairly accurate range estimator. As it is, this is just going to be good enough to estimate the range of the object from you. Kind of neat to try and the price is right.

[GoldKey]

It is saying that it is accurate in measuring the distance of a person to within 10 feet at 200 feet. This is a 5% variance. Assuming no variance in the user and that they have measured the length of their arm exactly, they are still missing an important piece, you don't know how tall the person is that you are measuring the distance of average height varies by more than 5% and that variance would multiply the inaccuracy of the distance being measured.

[rhmorrison]

This doesn't seem all that practical to me.
I have to agree!

Even though all PocketPC's have a 240 x 320 resolution they have DIFFERENT SCREEN SIZES and this would have to be calibrated for the screen size (I don't have the software maybe they do this). Otherwise I think it's an interesting application that might be useful in some specialized areas (where the size of the object is known and fixed).

[Cortex]

i havent tried it but there are 3 issues:

1. holding the device at different distances from your eyes will cause error
(as pointed out above)
2. the relative size of an object will increase the error as it gets smaller (ie is further away)
3. small objects will have larger error in estimating distance

not to mention how impractical it is to enter a matching photo into the device in advance.

how about this idea: hold your pocket pc at arms length with the calculator opened. walk to the object would like to use the range finder for and multiply the number of steps by 3 to have the "range finder" calculate the number of feet to the object :lol:

[david291]

I wonder if the database includes a picture of their product. Cause I'm really far away from purchasing it.

[kiwi]

heh,

gee guys..., you're quick on the mark to diss the software.

I think its a neat application of the PPC *if* it works to some degree.. and ofcourse there is room for error in the application. Its good to see developers making innovating software.. like when people wrote software to use non-consumer IR in the PPCs to control TV sets.. yes, they only worked for a few feet, and narrow line of sight, but hey, that's really cool..
This sort of development kicks ass on any pacman clone IMHO

cheers

B

[GoldKey]

heh,

gee guys..., you're quick on the mark to diss the software.

I think its a neat application of the PPC *if* it works to some degree

B

We are "diss"ing it specifically because it does not appear that it will work to any degree to make it useful. I think it is more of constructive critisism. I will give the developer credit though for thinking outside the box.

[Jeff Rutledge]

I agree with Goldkey. There doesn't seem to be much practical use here, but it's very cool to see new and innovative uses for these devices.

[SandersP]

This will become practical once built in camera is popular in PPC.

[149125198]

I sincerely think it is not at all useful and seems pretentious to me. I tried it with the trial version. Afterall, it relies on the judgement of the user!

[MonkeyGrass]

I wonder if the database includes a picture of their product. Cause I'm really far away from purchasing it.

ROFLMAO

:lol: :lol: :lol:

[PatrickD]

The guy in the picture had better be quick. At 200mph those cars will have flashed by in less than a second. By the time he figures out how far away they were, the cars will be on their third lap. :)

[qmrq]

I couldn't help but laugh when I read this.

This made me laugh even harder..

I wonder if the database includes a picture of their product. Cause I'm really far away from purchasing it.

:rotfl:

[Don't Panic!]

It should work fine on a golf course. This reminds me of the principle that is used with the inexpensive optical range finders golfers sometimes use. The height of the flag is a known factor and screen size and arm length can be factored in. I'm going to try this when I get back from New York.

I'm just glad the developer was sesible enough to keep the price low. No one would even consider buying this if it was over 10 dollars IMHO.

Don't Panic!
Bobby

[Pat Logsdon]

:huh:

This rangefinder (http://home.houston.rr.com/molerat/rngfndr.htm) would be much more accurate. No database required! :mrgreen:

[kiwi]

heh heh.. I actually thought it was a joke.. until I realised it was serious.

btw - I havent installed it either.. :)

maybe one of those Laser distance thingys could be integrated in a CF card to a hardware solution to this sort of functionality.. kinda like that CD card that had IrDa.. which with the newer PPCs has become obsolete..

[Kiyoshi]

Heh, I'm an avid golfer and I wish there was some cheap way to have a rangefinder in your PPC........most normal laser rangefinders are $200+ and i'd rather buy a new golf club or a shiny new WM2003 device for that much money 8)

[ctmagnus]

maybe one of those Laser distance thingys could be integrated in a CF card to a hardware solution to this sort of functionality.. kinda like that CD card that had IrDa..

That's what I was thinking. A purely software approach to this kind of thing is a dumb idea, unless accuracy means very little to you.

[David Prahl]

I just thought of something else, too: sunlight has NEVER made it easier to read a Pocket PC screen. Can anyone think of a SINGLE practical use?

I agree with SandersP that a camera would greatly help the accuracy (assuming the image databate was vast).

[szamot]

This just goes to show that some inventions should have never left the head of the inventor. I won't even bother with a free trial.

[kiwi]

Heh, I'm an avid golfer and I wish there was some cheap way to have a rangefinder in your PPC........most normal laser rangefinders are $200+ and i'd rather buy a new golf club or a shiny new WM2003 device for that much money 8)

Isnt there a GPS solution for Golfing? Ofcourse your Golf course map would be required.

[zedev.com]

Hi guys,

Thanks for the comments. I just wanted to address a couple of questions that came up.

Overall, the biggest complaint here seems to be that Pocket Rangefinder isn't 100% accurate. Absolutely correct. Pocket Rangefinder isn't designed to replace your $200 laser rangefinder. Instead, it's a guide that for $6 will greatly improve your naked eye's ability to estimate distances.

Also, the PPC would have to be an exact distance from your eyes for it to work correctly. Do they include a string?

If you face whatever you're measuring and hold your Pocket PC out at arm's length with your arm fully extended, you actually might be surprised at how repeatable it is. In the tests I did, the distance only varied by a couple percent.

Even though all PocketPC's have a 240 x 320 resolution they have DIFFERENT SCREEN SIZES and this would have to be calibrated for the screen size

To account for different screen sizes, all you have to do is measure the height of your screen with a ruler and enter it in the Options dialog in Pocket Rangefinder.

they are still missing an important piece, you don't know how tall the person is that you are measuring the distance of average height varies by more than 5% and that variance would multiply the inaccuracy of the distance being measured.

Correct. This is a problem that all optical (versus laser) rangefinders suffer from -- you need to know how tall the thing you're measuring is. If you're measuring the distance to a person who you know is exceptionally tall, you can input his height into the program with a couple clicks, and the distance will be calcuated with that in mind. If you don't know someone's height, the error usually isn't that great. Let's say you see a 6'2" (188cm) man but you think he's only 5'10" (178cm) -- that would only add an additional 5% error to the measurement.

Anyway, thanks for the feedback. If you have any questions, post them here or send me an email at [email protected].

Zach
Ze support