ArchimedesMB 2.1.0.24 - Free Download

[jamac]

Thought it might be of interest to visitors to this forum that ArchimedesMB is finally available for public release.

We have opted for a liberal "Free for non-commercial use" license and as such there are no restrictions/unlock codes to download and use.

We have placed a nominal fee on commercial use (again controlled by trust in our users) to assist with development, website fees and paying for commercial plugins we use in the software.

This is the first of regular releases now that the new hydrostatics core has been implemented and we look forward to receiving feedback on user experiences.

Best Regards

John

[Robert Gainer]

John,
The link on your site is wrong. Change it to,
http://www.naval-architecture.co.uk/...beta_issue.zip

[jamac]

Robert,

Many thanks for pointing that out. Spelling mistake in the original link.

Best Regards

John

[DanishBagger]

Still hoping for an OS X version

[jamac]

Sorry about that but development for OS X is not planned in the immediate future. With new Macs running intel chips though, who knows what cross platform emulation will be possible.

Thanks

JA

[DanishBagger]

Very nice, Jamac. So, here's to the future [lifts cup of coffee in a laid back toast]

Andre

[Andy]

Just to say well done to John for doing this - he and Martijn (Freeship) should be applauded for their efforts!

Andy

[tandu]

Hello,
Thanks for your work!
I hope to make some feedback for you and for the "boat design" community.

Giuseppe

[JonH]

Thank you for work on this, I'm still feeling my way through the absolute basics of design but I'm exceedingly grateful for your product (and, of course, for Free!Ship)

Originally Posted by DanishBagger

Still hoping for an OS X version

Admittedly it will be verrry slow, but what about Virtual PC ?

[DanishBagger]

Jon,

Very true, it _will_ be very slow, and I would need to have XP installed - that in itself would be like drilling holes in you boat, while not wearing a life vest

[jamac]

Andy, tandu & jonh,

you are all very welcome of course. Please use the software and give me crits so I know what people want to see added in the future.

John

[Tim B]

One thing I noticed importing from Rhino was that what had been my standard X-long, Y-Port, Z-Up system was now rotated through 90 degrees to become Y-Long etc.

My first question is a) why? and b) why can I only rotate the imported GHS file about the Y axis. Surely it's not a programming problem, just an oversight.

Secondly, Persisting none the less as Z is the correct way up still, Are waterlines taken as the planes in which z=0, z=1 etc.? and if so, why does it talk about water-lines from the Y-origin, and why do I get negative volumes for waterlines that are less than 0 but clearly still in the hull.

Thirdly, the only stability graphs I can have are cross-curves, (or so it seems) which may be fine for big ships, but couldn't we have a normal GZ curve for the yachties?

All in all, it's professionally put together, and some of the volumes I got were right. It runs under wine on linux.

The major thing against it for me is that it doesn't seem to be finished yet.

Tim B.

[jamac]

Hi Tim,

Many thanks for your feedback below. In answer to your questions:

One thing I noticed importing from Rhino was that what had been my standard X-long, Y-Port, Z-Up system was now rotated through 90 degrees to become Y-Long etc.

The Archimedes coordinate system is Y = longitudinal axis, X = transverse and Z = vertical

My first question is a) why? and b) why can I only rotate the imported GHS file about the Y axis. Surely it's not a programming problem, just an oversight.

Archimedes data is based on sections through a hull, perpendicular to the long axis. A system used by most other hydrostatics packages. This modelling system only lends itself to rotation about Y axis (i.e. heel). You can effect rotations about other axis in two ways either modelling (i.e. change the model to reflect the new orientation and work out the new sections perpendicular or the Y axis) or post processing (i.e. work out effect of rotation on appendages based around hydrostatics propoerties and waterplae interias for apendage orientated about Y axis). Both of these are unstatisfactory as they introduce assumptions (the latter less so though).

My plans for this are introducing a new element based around paneled surfaces which allow a definitive description of a volume. These would be used in conjunction with std section based appendages and allow mixing of the two models (eg pontoon on a semi sub modeled as section data with the legs and decks defined as cylinders and a cuboid). This is down the line though unless I get feedback otherwise.

Secondly, Persisting none the less as Z is the correct way up still, Are waterlines taken as the planes in which z=0, z=1 etc.? and if so, why does it talk about water-lines from the Y-origin, and why do I get negative volumes for waterlines that are less than 0 but clearly still in the hull.

Correct waterplanes are planes which at trim = 0.00 deg (m) are normal to Z Axis. If the waterline is trimed then the z location of the waterline varies as you move along the Y axis, therefore a point of reference to which waterline positions are worked out is required. You can select this to be Y=0.00m or use a user defined draft mark location (which are just different locations on Y axis the user can specify). This assumes that BOK is at Z=0.00m.

Negative Volumes - This must be a bug. Can you pass the model that gives this and I can ensure it is fixed?

Thirdly, the only stability graphs I can have are cross-curves, (or so it seems) which may be fine for big ships, but couldn't we have a normal GZ curve for the yachties?

Yes...This is on the hit list. Next is longitudinal buoyancy curves (complete with back end structures that allow per appendage buoyancy and weight curves to be worked out). This will form input to the load balancing system and allow solving for given weights and COGs while allowing free trim condition. With this done, the KG curves that take into account changes in trim as the vessel heels can be worked out. As things stand, the KN curves can be exported to a spread sheet and the KG curve worked out very easily (please email me for a sample that works with Archimedes) but it does not take into account shifts in LCB as the vessel heels. But it soon will.

All in all, it's professionally put together, and some of the volumes I got were right. It runs under wine on linux.
The major thing against it for me is that it doesn't seem to be finished yet.

Correct and it never will. Development will be ongoing but will be happy once the next two releases offer long buoyancy and solving for load conditions. Road map is two months for completion on this.

Will continue to update the manual and help file and these now available seperately as a download. Will make these points regarding the coord system clearer with some illustrations. Give me a day or so to get this done.

Thanks again for the feedback and please remember to send the file you are getting the errors with.

JA

[Tim B]

I will e-mail you a hull on which the volumes go negative, but it will not be the one I first had the problem with, I'll find another that does the same thing.

Incidentally, is there any reason for hydrostatics packages using Y as Longitudinal? All the text-books I've read (and people I've spoken to) usually use X as longitudinal.

Tim B.

[ABoatGuy]

Tim B. et.al.

The coordinate system would be a great thing to standardize in this industry. I believe most are using X for length, Y Stbd, and Z vertical. Yes-No? Is there major software out there that uses something different.

I know the GHS export in Rhino will let you adjust it, which is a good thing. AutoShip/AutoHydro uses L-T-V (Longitudinal, Transverse and Vertical) which exports to X, Y,Z.

Any thoughts?