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The prposed device is a digital camera with an optical zoom lens. Coaxially mounted with the lens is a laser pointer (high powered, for outdoor use) and an ultrasonic (or laser) rangefinder.
When a picture is taken, recorded with the image is the distance to the dot projected by the laser pointer.
Want to survey an area ? Will you fit a marquee, a funfair, and a small arena in that small bit of fenced-off parkland ? Just how far is the back fence from that new house you just looked at ? Easy to find out; no pacing round with measuring tapes, or blurry small-scale maps. Walk round the site and photograph it, then go home and do the analysis on your PC.
Photogrammetry
http://www.arctron....ing/Photogrammetry/ Kinda the same but inside out [squeak, Oct 04 2004, last modified Oct 21 2004]
Top boys
http://www.leica-ge.../products/index.htm V. complex,v. efficient, v. expensive [squeak, Oct 04 2004, last modified Oct 21 2004]
WARNING: WELLHEAD PIPEWORK UNDER HIGH PRESSURE.
The_20Incredibly_20...Mixed_20Up_20Zombie " =-0 " @ /|\ [8th of 7, Sep 04 2012]
Kickstarter: Spike
https://www.kicksta...nt-and-modelling-on Mentioned in my anno [notexactly, May 28 2019]
Kickstarter: iPin Pro
https://www.kicksta...nto-a-smart-laser-r Mentioned in my anno [notexactly, May 28 2019]
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Annotation:
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All it needs is differential GPS to record the camera's position too and you could move it between shots for areas that can't all be seen from the one spot. |
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Isn't this called a theodolite? |
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No, it's not a theodolite. We already have a
theodolite. |
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1. Basic theodolites don't measure distance
directly (but it can be inferred by
triangualtion). |
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2. Theodolites don't take pictures and record
ranging information on the picture. |
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Is it a Distance Meter then? |
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Yes, Rods. Redeye wouldn't just spoil the picture... |
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Could you mount it on a gun? "See, I shot the attacking alligator at three yards!" |
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Basic theodolites don't do this, but there most certainly are high-end models available with integrated range finders. (I know Wild-Heerbrugg aka Leica makes them, as I used to work for them). |
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I worked on a software control system that would not only collect data from such instruments, but would actually aim them as well, using servos. The end result is you could get a complete surface map of an airplane wing or other large structure without lifting a finger. It was quite amazing to watch the things clicking away, moving their little laser spots and measuring it automatically using an integrated camera. |
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[krelnik] - was there just one distance data point per image? Your anno made me think of a image format and camera that would take the picture, then scan with the measuring laser and tag every pixel with range information. Then when you view the picture on your computer monitor, the range to anything in it shows up onMouseOver(). |
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[oneoffdave] Encoding GPS location
information and bearing would be useful. |
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[krelnik] We know about high end theodolites,
and how much they cost. [UB's] mention of
the ultrasonic rangefinder - like the Polaroid
modular system - is about the thing we had in
mind. |
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The idea is for a relatively low cost (<
USD$500) device that can quickly and
accurately record distance and imaging
information. In fact, we think you could make
the whole thing for less than USD$200 in
quantity; aimed into the Serious DIY/Low-end
commercial markets, and idiot proof so that
even a Manager could use it. |
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(No, forget that. Too much effort). |
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//one distance data point per image//
Well, there wasn't really an image that was kept per se. One theodolite would project a laser spot, the others would rotate until they were aimed at it and measure its relative position. Rangefinding was used at first to calibrate the relative positions of the instruments. |
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//how much they cost//
Yes, the instruments I mention cost a ton of money, more than a nice car. I definitely like the idea of providing a low end version. |
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How does the integration function work when you take it back home? I.e. I have 14 photos in the camera that are in various directions, how do I then put that together into something useful. Manually? Could something like QuickTime VR's "stitch together" function help? |
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The company I work for do this but the other way round if you know what I mean. The surveying is carried out first using a total station (or tachymeter if you prefer) and the control points are marked off in a grid. |
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Then, the site is recorded using digital cameras and the resulting images are then rectified on computer to fit the surveyed points (stretched around to make up for lens distortion). |
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So the two processes are used but not to find out distances, the distances are used to rectify photos for accurate documentation. |
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The problem with surveying using a digital camera is that you have no way of levelling or stationing it. |
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When it comes to surveying etc. there are some extremely advanced devices knocking around but none of them are small enough to be carried around. |
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Surveying measures in 3D but if you only want to measure distances between objects or surface areas, I'd stick to the old tape measure. |
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Surely there would be legal issues with this idea? I am sure some lawyers would argue that the original designer of the fenced-off parkland retains copyright in it, and that by measuring and photographing at the same time you infringe his IP. I would think that a good legal team could sue you till you are as small as a newt. |
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GET THOSE BOLTS TIGHTENED DOWN! Looks
like we have a bit of seepage through from
the other idea ... better stack some long-
haired besandalled pot-smoking hippies
round the wellhead to soak up any dribbles
of formal logic. |
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//The problem with surveying using a digital camera is that you have no way of levelling or stationing it. |
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Put it on top of a theodolite..hang on... |
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Baked in 2014 and 2018: [links]. The camera is of course
now a smartphone. The laser is parallel to the camera's axis,
not coaxial, but the same goes for "coaxial guns" on tanks. |
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// Baked in 2014 and 2018: [links] // |
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Ahead of the curve, as usual. |
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// The laser is parallel to the camera's axis, not coaxial, but the same goes for "coaxial guns" on tanks. // |
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Actually, "coaxial" is correct; it means "sharing the same primary axis", not "having a common primary axis". A "coaxial" cable is correct, although what is commonly called a coaxial cable should properly be referred to as a "concentric" cable. All multicore cables are in effect coaxial. |
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The phrases "sharing the same" and "having a common" are
synonyms, AFAICT. |
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