bow-simulator

[lleroy]

she couldn't figure out why it won't work on mine. I get these error mesg. Anyone got a clue what's happening

what computer are you using Win10? (or older: win7? Vista?)
looks like the program has a problem initializing your graphics card's 3D support...

[DC]

It was Win 7 Home Premium when I bought it who knows how long ago. It's Win 10 now. It was a bare bones computer so the graphics card may not be much. I wouldn't want to spend money on a card and then have the computer die(again, I've replaced the hard drive) decision time I guess. Thanks

[stfnp]

Hello everyone,

I'm the author of that program, willie has pointed me to this thread. I'm glad some of you like it and find it useful. Keep in mind that it's not yet finished by far. It's more of a starting point. That's also why I'm always interested in suggestions and feedback.

I get these error mesg. Anyone got a clue what's happening

Yes, that's a problem with the 3D graphics, as lleroy said. Sorry for the inconvenience. The next version of the program should be more compatible with older hardware. I hope to get it ready in the next few months...

Stefan

[DC]

Thanks. I just went looking at 3d graphics cards and they range from $9 to $900. Yikes!!! I hate to spend a bunch of money on an old computer. Can anyone recommend a cheap card that will run this program?

[willie]

Stefan,

the energy graphing is a real eye opener, especially being able to see the relative proportion of bow/string/arrow energy. Did you utilize the marlow formulas to work up your algorithms? I am guessing that you have tried to verify some arrow velocity predictions with a chrono?

quite a project you have in the works

[stfnp]

Thanks. I just went looking at 3d graphics cards and they range from $9 to $900. Yikes!!! I hate to spend a bunch of money on an old computer. Can anyone recommend a cheap card that will run this program?

What graphics card do you currently have? You could try installing the latest drivers from the manufacturer's website, if available.

the energy graphing is a real eye opener, especially being able to see the relative proportion of bow/string/arrow energy. Did you utilize the marlow formulas to work up your algorithms? I am guessing that you have tried to verify some arrow velocity predictions with a chrono?

I have read that paper from Marlow and applied some of the results to my own model. But it's a different approach. My program uses finite elements, so the limb and string are approximated by a large number of little "segments" or "elements" connected to each other. There is an unfinished technical documentation here if you want the excruciating details. Unfortunately I don't have a chrono yet. Might be a good investment though... For now I have only verified some of the static results with simplified test bows.

[willie]

I have it working on Windows and on Linux
(I even have compiled the in-development version :-) since It's open-source )

lleroy,
I tried to look at your .bow files in the appimage version, but they would not load. What version did you use to create them?

[willie]

a little research about FEA has been on the reading list for a while,  so this might be a good time to start, thanks.

[lleroy]

I've made them using the self-compiled version, that's somewhere between 0.5 and 0.6.
(if there is interest, I will remake them so that they open in the latest-released version, ie: 0.5,
but that may not be before next week)

I have it working on Windows and on Linux
(I even have compiled the in-development version :-) since It's open-source )

lleroy,
I tried to look at your .bow files in the appimage version, but they would not load. What version did you use to create them?

[willie]

lleroy,
that might explain, if the .6 is unreleased. no need to redo unless you just want to share, as I was just curious.

[willie]

this project has become Virtual Bow.

Is anyone using this program? Thoughts and comments if you are.

I can't figure out what the expected input for the width is.

I learned to use it more this past winter, although I have not built a bow with it yet. The program is actually very useful for laminated bows.

widths are stated in meters at some percentage out the limbs length. the table does not have to be in order

[Don W]

I'll try and work through it. I have a few hickory stave drying I can try it on. I have a few other to finish first, but maybe I can figure the program out in the mean time.

[willie]

It will be interesting to see what you come up with.  If your hickory is from the same source, you can model an existing bow to solve for the required MOE (stiffness), then easily tweak the model into an improved design. The data entry method in virtualbow was developed for ease of reverse engineering.

[SLIMBOB]

I don’t make glass bows, but I know a guy who does. Programs like this are what he uses to experiment with different design tweaks. For an all wood bow, to many variables to be accurate I think, but maybe a useful tool for an experienced guy to, once again, tweak the designs here and there. If used as a shortcut to simply bypass the design and tillering stages, you kinda missed the fun part. My 16 year old son would disagree with most of the above.

[lleroy]

I used this program to make a some virtual bows, to see how a specific design works, and understand how it's spreading the stress along the limb. So for me it's an interactive version of the TBB where you can produce F/D curves and experiment with profiles.

It's much easier to make a virtual bow an inch longer or 1/8 inch wider than a physical bow :-;

I haven't used it as a "design" tool, but it's a valuable learning tool.
(as mentioned above, too many variables in real wood compared to laminations)