Speed boat simulator in development

Discussion in 'Boat Design' started by Todd Wasson, Feb 24, 2015.

  1. Todd Wasson
    Joined: Feb 2015
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    Todd Wasson Junior Member

    Hi, folks. I'm developing a speed boat simulator that some people here might find interesting because it's possible to shape your own hull with it.

    http://speedboatsim.com/

    While it's not for sale and there's no demo yet, hopefully in the next few months I'll have something people with a decent gaming rig can try for free and buy at a reasonable price.

    I'd love to get some feedback from you guys. Let me know what you think, you might even influence how it develops! Feel free to leave comments and questions in this thread or on the web site itself.

    Mods: If this isn't the right forum for this, let me know and I'll delete and repost this somewhere else (or you can just move it as you see fit). I figured the "boat design" area might be as good a place as any seeing as this simulator lets you design your boat. :p
     
    Last edited by a moderator: Jun 17, 2015
    1 person likes this.
  2. kerosene
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    kerosene Senior Member

    I guess for the population here the interest is in how the planing is calculated and how accurate it is to the real world. For a game a rough system that looks about right is enough but for real world boat design you need more.
    The environment graphics look good. From gamers perspective I am not sure how can you get enough fun factor to keep a player glued to it for longer periods of time.
     
  3. Todd Wasson
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    Todd Wasson Junior Member

    Yes, I wasn't too sure about posting it here at a boat design forum. It's not high fidelity enough to use for real boat design, this has to run in real time after all. It does a pretty good job of getting the basics right, mostly what I was interested in was the flying behavior where you're clipping along with just the stern skimming the water. It seems to do that and a couple other things pretty well.

    Funny you should mention planing: What I do is treat the water as being a stationary fluid. This works great once you're planed but it's not good at all at lower speeds because no bow wave develops. For very low speeds I had to fake it by adding a force that moves in a manner meant to very roughly approximate a bow wave being present. This goes away as you speed up beyond the bow wave speed where you're fully planed. So at very low speeds it's indeed faked, otherwise it planes so gently you barely notice it.

    So yeah, this is meant more for entertainment, not for real boat design. I figured some folks around here might get a kick out of it at least as something not quite so serious. It's possible though that this forum just isn't the place for this. If that's the case I'll just slip quietly away into the horizon, I found a few forums where people are going a bit nuts over it and thought this one would be worth a shot. You never know until you try, right? :)
     
  4. DavidJ
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    DavidJ Senior Member

    Looks pretty cool.
     
  5. Kailani
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    Kailani Senior Member

    I would have spent days mocking up different hot boats with this when I was young.
     
  6. Poida
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    Poida Senior Member

    It may be good as a sales gimmick for people selling boats.

    Poida
     
  7. Todd Wasson
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    Todd Wasson Junior Member

    Thanks, DavidJ.

    Kailani: That's exactly what I spend most of my play time on this doing. I start with a 150 HP or 175 HP engine and keep tweaking the hull to get the best top speed with minimal porpoising and hopefully no chine walking while experimenting with different prop pitches. Once that's maxed out I'll go up on engine power in 25 HP increments up to 300 HP, repeating the process the whole way. It's interesting how a 150-175HP 60 mph hull really needs to be different from something that runs in the 80's or 90's. Suddenly you start paying a lot more attention to pad design and so on. It's good fun.

    Poida: Funny you should say that, yesterday Reindl contacted me about adding one of their bat boats into the sim.

    http://speedonthewater.com/new-boats-engines/1959-reindl-building-ilmor-powered-bat-boats
     
  8. Todd Wasson
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    Todd Wasson Junior Member

    Last edited by a moderator: Mar 5, 2015
  9. daiquiri
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    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    It looks very interesting and well-done. The dynamics of the powerboat seem to be captured pretty well (at least qualitatively).
    The blowover also seem to be modeled pretty well, and I would be interested to learn a bit more about the physical model you have used. Where did you find the aerodynamic coefficients for calculation of aerodynamic lift, drag and moments?
     
  10. Todd Wasson
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    Todd Wasson Junior Member

    Thanks. :)

    There aren't any lift/drag/moment coefficients in the simulation. It's more akin to an FEM model. All the forces are computed on a per triangle basis directly on the boat mesh using velocity, fluid density, triangle area, and so forth, in a direction normal to each triangle face. To model skin friction (force component in each triangle's plane) I'm using Reynold's number, each triangle has its own value that changes over time based on the distance from it to the waterline/hull frontmost intersection. Aerodynamic versus hydrodynamic is handled strictly as a density change of the fluid, so that particular force is either one or the other on a given triangle. The mesh triangles cutting the waterline are divided into three with two on one side of the water plane and one on the other so that each triangle sees only one fluid density.

    The major approximation I'm making here is that the fluid itself does not move. There is no flow field per se, rather the flow velocities at each triangle are taken to be the velocity of the triangle centers themselves. Given the approximations and simplifications there, it works surprisingly well.
     
  11. Todd Wasson
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    Todd Wasson Junior Member

    1 person likes this.
  12. gonzo
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    gonzo Senior Member

    Very impressive
     
  13. snowbirder

    snowbirder Previous Member

    Really cool real time simulation.

    The interaction with the water and rooster tail are impressive as are the crashes.
     
  14. Todd Wasson
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    Location: St. Paul, MN

    Todd Wasson Junior Member


  15. Todd Wasson
    Joined: Feb 2015
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    Location: St. Paul, MN

    Todd Wasson Junior Member

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