scanner

[peter radclyffe]

can anyone tell me about a scanner for half models,
thank you

[Lister]

Sorry, I don't even know what is a scanner for half model.
Can you take lines old fashion from the half model?
Lister

[peter radclyffe]

i can but its time consuming on a solid model

[Tad]

A camera and software......

http://www.accurexmeasure.com/dpapro.htm

[peter radclyffe]

thanks Tad

[MikeJohns]

Peter 3D scanners are used a lot by historical societies, museums and the film making industry. The laser scanners are accurate to around 1mm.

The photographic methods with markers doesn't work well in my experience.

[ACuttle]

Laser scanners produce very mixed results depending on surface finish and scanner type.

The units I've worked with typically gave 1-5mm accuracy which was fine for full sized hulls but wouldn't be much good for a model. A high accuracy scanner, maybe a desktop model might get things done for you but accuracy might still be an issue. I've worked with people doing photogrammetry work for sonar mounts at VT and their kit was giving nm accuracy which would likely be overkill for you.

For a half-model, if it's of a usual size, I would recommend a measuring arm, they produce similar results to a scanner but let you choose the areas that need more definition - bows/transoms etc. Accuracy should be what you are looking for, they're often used by the automotive industries for component QC and measuring of models and forms.

These people are suppliers of the gear but they'll give you a better idea of what is available, they do scanners and arms:
http://www.faro.com/SelectCountry.aspx

I would suspect that the kit resellers will would be able to tell you who is offering services near to you - that's how I used to get a lot of business.

[MikeJohns]

The laser scanners are brilliant whether taking the lines of an existing ship or a model.

Look for a service similar to this:

http://www.3dspatial.com.au/services/marine.html

I think it's all magic after manually taking lines off a vessel.

Or make a mold fill it with wax and slice it into stations and you can trace around each station with a digitising tablet. Or trace onto paper reduce and scan into the pc on a std scanner.

[peter radclyffe]

thanks guys

[Tad]

Actually I think Nat Herreshoff's mechanical method probably will work as well as anything, presuming you fair the lines later anyway.........

[peter radclyffe]

so do i Tad, but who sells it

[gonzo]

Old Nat made his own. It only takes four sticks, a few screws, a C clamp, a nail and a sharp pencil. If you have the skills to build boats, this should be easy.

[Willallison]

I saw an article in a recent trade mag - possibly European Boatbuilder - for a new product that is designed to work with Rhino. It is a photo / markers system.
From my brief read, I gather it is primarily intended as a single use system - you supply some basic data about the boat, they supply the camera, markers etc set up and ready for the job.
Off the top of my head, I think costs were around 5000 euro...

I'll see if I can find the article or a link...

[DCockey]

Originally Posted by Willallison

I saw an article in a recent trade mag - possibly European Boatbuilder - for a new product that is designed to work with Rhino. It is a photo / markers system.
From my brief read, I gather it is primarily intended as a single use system - you supply some basic data about the boat, they supply the camera, markers etc set up and ready for the job.
Off the top of my head, I think costs were around 5000 euro...

I'll see if I can find the article or a link...

Sounds like Rhinophoto. http://www.rhinophoto3d.com/ It's been around for a few years though the new issue of Professional BoatBuilder has a piece about it. It appears the piece was written based on a press release, not first hand experience

With RhinoPhoto, coded targets are place on the boat or other object and a suitable set of photos are taken with a good digital camera. The photos are then processed with the Rhinophoto software and the 3D point locations of the targets are calculated. Pairs of targets can be used to measure and create offset points for edges and similar where targets cannot be placed directly. Since RhinoPhoto is a plug-in for Rhino I assume the points "automatically" appear in Rhino. The user then creates the desired 3D model in Rhino using the 3D points and any other information they have available. This is similar to what would be done with points obtained from other measurement methods. The Rhinophoto website has a series of videos showing the use of Rhinophoto to measure and create the tugboat hull surface shown in the PBB article. RhinoResurf, a separate Rhino plug-in was used in the videos to create the surface.

[DCockey]

PhotoModeler is a standalone software package which has is similar to Rhinophoto but has some additional capabilites. www.photomodeler.com In addition to coded targets PhotoModeler can use simple dot targets, and the user can also manually mark corresponding points on sets of photos. In addition to points PhotoModeler also can calculate the 3D location of straight lines and edges, and cylinders. There is also some capability to capture 3D curves. The 3D geometry from PhotoModeler can be exported in a variety of file formats including .dxf, .igs, .3dm, and .wrl.

I've used PhotoModeler to measure several boats and have found the additional capabilities beyond coded targets to be very valuable. I use PhotoModeler to process the photos and obtain the 3D points, edges, cylinders, etc. I then export them and import into Rhino where I create the 3D model of the boat. So far I've used the native Rhino commands to create the models.