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Grant-53
recumbent guru

USA
526 Posts

Posted - 12/06/2014 :  09:41:43  Show Profile  Reply with Quote
I use a 7" tall toy wrestler figure. This is a 1/10th scale size that matches the motorcycle model figures. I can work in dual dimensions of inches and mm. My family suggests that I offer full size templates for sale rather than 1/4 scale drawings or computer files. For those of us using various software it would be ideal to design shells, CFD model them, and then use paper model programs to create template files I could take to the printer. See my degree in Computer Integreted Manufacturing isn't wasted.
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warren
human power expert

USA
6049 Posts

Posted - 12/06/2014 :  14:53:11  Show Profile  Visit warren's Homepage  Reply with Quote
I played with it a bit. Things get funny if you make the rider too upright or laid back. It would be nice to see the entire left half fairing instead of the 1/4 fairing displayed. For some reason I had to click on a menu option to enable the check boxes at the top of the screen. Does the grid have a scale?

How would I make a SWB frame?

Thanks,

-Warren
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Runxner
recumbent enthusiast

USA
441 Posts

Posted - 12/06/2014 :  17:02:51  Show Profile  Reply with Quote
Warren You can ignore the front wheel and drag the nose SWB?

Shooky
1. When seat controls front-back is on the back half of the slider the legs disappear.

2. Clicking/seeing the tug points is difficult on 90deg views

3. Mouse controls are reversed between front view and back view.(backview right mouse moves tug left.)

4. Cranks should move in unit with seat front-back.

5. if you can't adjust wheel size it's sort of irrelevant

6. If you could adjust wheel size then you should be able to adjust crank height.

7. Tugs can be pulled opposite of center & get concealed inside rider body& wheel making one mistake hard to recover design from. Enable ctrl Z?

Good work, just pointing out what's needed to keep your program usable for the most users.

Team Low-Life
Lowracer Test Pilot/Evangelist

Edited by - Runxner on 12/06/2014 17:04:06
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/07/2014 :  19:03:11  Show Profile  Reply with Quote
Appreciate the feedback from everyone. I'll try to address these issues. Some of them I knew about, a few I actually mentioned but most are new things to do.

Warren: I want to add a frame designer to this and have made a bit of progress in that direction. However here's something to play with.
-- open the application directory. Included with the installation is a text file named "Mesh Descriptors.txt". In that file are a lot of tags (things with [TAGNAME] followed by data. The information in there is what I use to build the bike and current rider. Several lines of data comprise a "set". Most sets start with a [Name]"part name" format and ends with an [End] tag.

Again I hope to have a frame editor in the not too distant future. In the iterim, open your "Mesh Descriptors.txt" and find the area of the chain ring. Replace that block' ModelOffset with this (only replace the [ModelOffset] line, the rest is for your reference.

[Name]Chain Ring...
...
[ModelOffset]-1.3,.61,0
...
[End]

Edit the ModelOffset of the "Left Thigh"
[ModelOffset]-.4,.31,0.08

and finally the "Torso" block
[ModelOffset]-.4,.31,0

See what that gets you. The frame is described in the area below the
//frame
line but it's not terribly relevant.

Check the "show rider box" and "show tug marks".
Slide the rider box and tilt it appropriately and with the seat controls, hopefully you can get where you're going in the absence of a much better user interface.


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shooky56
recumbent guru

USA
544 Posts

Posted - 12/07/2014 :  19:28:26  Show Profile  Reply with Quote
Runxner: Yes your advice to Warren is basically correct, my prior post was to move the rider and crank to the wheel but he could just move the wheel toward him also, although neither is needed, more important is his height, seat lean and the crank height relative to him.

1. Yes. LOL I thought about limiting that slide to not let you yank your legs apart (OMIGOD MY LEGS ARE GONE!).

2. Clicking the tug points. Not only is that difficult but possibly impossible. To remedy this there are radio buttons toward the upper right to let you select them manually. Basically I do a screen scrape of the mouse position to determine the color. Each one of those blue tabs is actually a imperceptibly different shade of blue. I flag and the one you click and actually select the radio button for you if you do this from the screen. However some views or, if the tab gets behind the shell it is impossible to mouse select it (it's not the right color anymore). The only answer is the radio buttons. One thing I wish I'd added (which is easy) is change the tab color for the selected tab.

3. Yes it would be that way. I probably will push this toward later stuff though as I'm not sure there's much value from dragging the boxes from the back side.

4. Actually I disagree with that one. The frame designer should allow that for sure though. The seat slide importantly lets you work your body into the correct knee scissor angles (roughly 140 at the most open). This angle effects maximum knee height and therefore the shell's needed shape.

5. Wheel size et al. will be in the frame designer. In the interim you can locate the wheel's data in the mesh descriptors file.
[Radius].47 changing that will change the wheel's diameter (1 = 27.8 inches btw, had told Warren 1 = 24 but that wasn't quite correct). Radius of .47 = diameter of .94 * 27.8 = 26.1" diameter.

6. Again, part of the frame designer.

7. Tug issues have been discussed but the Ctrl-Z thing. You know we have a joke. In the shop, when a fresh outta college kid would walk in, we'd tell him we needed an undo for this or that. Invariably the conversation from him began "all ya gotta do is". A week later they'd come back and go son-of-a- I had no idea. Ctrl-Z is a good idea but a real PITA to implement. The save file feature is 1/2 second away (it auto saves to default.hpv or your last save). You can save the file as a "keeper spot", then save as a "working file" then "save" "save" "save". Once you're pretty happy, save another keeper spot.

I don't mean to say no, everybody likes an undo but boy those get real ugly real quick.

Oh Warren: 1/4 fairing? Actually that is supposed to be the entire left side. Can you email me a screenshot of what you see?

My nephew has also played with this some and mentioned he'd like to have a switch for a full shell (both halves). A slider to solidify the shell (transparency setting) and a color selector. I was working on the color selector (how I'd do it in my head already).




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shooky56
recumbent guru

USA
544 Posts

Posted - 12/07/2014 :  19:42:28  Show Profile  Reply with Quote
OK, Hopefully I've covered most of the feedback. What I've been doing.

Mostly working on the GUI. I've added a rider designer page that doesn't work and soon to add a frame designer (have a selector for it already) that won't work either.

What I have done, and this is almost completely irrelevant to functional needs, is add a mesh importer. If you have ever seen the "makehuman" project, they create very, nearly photo-realistic human surfaces. I can now import those. Still unimportant to building frames other than "good models" ensure "good fit before building", it adds some pzazz. My latest work has been in the area of texture importing. Textures of basically pictures. If I can load a texture it is essentially "shrink wrapped" to the shape.

What I'd like to get done before I release another version is at the minimum, a printer dump for the shapes in a scale. Grant suggested 1/10th scale and that sounds good although a user selectable scale is probably only slightly harder.

Work on it every day at least some. Today was busy. My Dad is 92 and went into the army in 1942. He fought across France and was staged in the Phillipines to invade Japan when the war ended. Our church asked him to get up front and talk about it. We all went to eat. Then my doctor (also rides with me) and his family had an open house, 21 rooms and 25 Christmas trees... wow! Indirectly you can thank Dr. Coulter for this, if you like it. You can curse me if you don't :) Doc's the guy that almost fell, I fell not killing him, shattered my front teeth, broke my hard pallet and said... "I'm getting my rump closer to the ground."... and started building an HPV.







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shooky56
recumbent guru

USA
544 Posts

Posted - 12/08/2014 :  13:16:01  Show Profile  Reply with Quote
quote:
Originally posted by warren

I played with it a bit. Things get funny if you make the rider too upright or laid back. It would be nice to see the entire left half fairing instead of the 1/4 fairing displayed. For some reason I had to click on a menu option to enable the check boxes at the top of the screen. Does the grid have a scale?

How would I make a SWB frame?

Thanks,

-Warren

Grid scale, missed that yesterday. Yes it is 12" squares, looks crummy because there is no XNA line draw. It's actually thin ribbons. All on the list.


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shooky56
recumbent guru

USA
544 Posts

Posted - 12/08/2014 :  21:42:51  Show Profile  Reply with Quote
Frame designer is going pretty well. You have a widgets box at the top and pick up one of three things, a wheel, seat or pipe. Need a crank yet. But you can deposit them on the page.

Cursor contains a tiny version of what you picked up until you drop it on the page.

Right now it means nothing, just a "paint program" but I'll capture the dimensions soon. Also need a regular bike seat and a crank.

lol, Grant I HAVE to have a ctrl-Z for this one. It won't be nearly as bulletproof a Ctrl-Z as we're used to but needs to be something.
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/12/2014 :  17:22:57  Show Profile  Reply with Quote
Just an update. Frame designer has progressed well. Mike you'll be glad to know I built an upright in about 3 minutes or so from scratch. Ended up with it over 6 feet long total (counting wheels) which is a bit long but still it was pretty easy. Need a top down view for the designer yet for the trike folks. Then I'll work on dumping the design to something that will work in the shell designer section.
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Grant-53
recumbent guru

USA
526 Posts

Posted - 12/13/2014 :  16:08:09  Show Profile  Reply with Quote
I expect a 3:1 shape to be at least 20" wide, 36 high, and 60" long. A shell 6-7 feet long would be within reason. I appreciate the effort having programmed in the bad old days of punch cards and Fortran.
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Garrie L Hill
human power supergeek

USA
1689 Posts

Posted - 12/13/2014 :  16:28:03  Show Profile  Reply with Quote
Cheese Louieeeze! I programmed back in the day using punch cards and COBOL. Fortran made sense ( to me ) while COBOL was just verbose and tedious.

Garrie "carbon based lifeform" Hill
HPRA Co-Dictator of the East
for pics of some of my time and money sucking projects
http://garriehill.winkflash.com/
and
http://s58.photobucket.com/albums/g277/cfbb/
and videos
http://vimeo.com/5513519


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shooky56
recumbent guru

USA
544 Posts

Posted - 12/16/2014 :  08:25:27  Show Profile  Reply with Quote
Grant: Yes I meant the bicycle itself. Had an error on the wheel sizes was what happened (since corrected) The shell in the demos is about 9ft 6in or so.

Punch Cards: As did I. Did not personally see it but heard a story (back in college) of a gal running with her 1000+ FORTRAN punch card program who tripped and dropped it and was crying about it. Any of us who existed during those times can also shed a sympathetic tear.

The newer tools are amazing. I wrote a flight simulator in assembly 84-ish (with shading; non-existent at the time). I wouldn't go back and do that again for love nor money!

The frame designer has been a bit more work than I'd planned, the side view is done but this also requires a top view and the swap between the two has been my most recent work. If you drop a "pipe" on the page, you need to size it, angle it and move it. That all works from the side. Now I got to get it to work from the top and the two views to play nice together (share the info properly).



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warren
human power expert

USA
6049 Posts

Posted - 12/16/2014 :  09:30:34  Show Profile  Visit warren's Homepage  Reply with Quote
You are doing the hard part now, actually making is useful. So many people give up their project at this point. Stick with it, it should be very cool when you are done!

-Warren.
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alevand
human power expert

USA
2871 Posts

Posted - 12/18/2014 :  18:41:34  Show Profile  Visit alevand's Homepage  Reply with Quote
I did a cubic spline interpolation of a naca profile and then revolved the points to form a 3d shape with elliptical cross section and then stretched and tugged here and there to make a fairing shape. I didn't progress from there because they wanted buco bucks to CnC the foam. I can try to find the interpolated data, if you think you might want to incorporate it into your app.

http://www.recumbents.com/wisil/levand/default.htm

C:
Tony Levand
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/19/2014 :  13:47:37  Show Profile  Reply with Quote
Thanks Tony! Actually that is almost exactly what this does only "by formula". The cubic spline fit equivalent is the direct use of the root formula that generated the profile you used.

The elliptical cross section, something I began with, has evolved into a user stretchable cross section. Although no longer honoring the elliptical desired shape, it does serve to minimize frontal cross-sectional area. A one day endeavor into which is best came away with "the extra frontal surface area needed to be pure elliptical created more drag than the smaller cross sectional area".

So I do appreciate your offering and perhaps someday will add a method to import existing shapes (at least ones that can be mathematically plotted like yours).

---

The frame designer is about as mature as I'm going with it for a while. Working on pulling that frame to the shell designer section now. Want to offer up a new release before Christmas. Lots of added stuff.
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/19/2014 :  17:03:12  Show Profile  Reply with Quote
While working on "putting all the pieces together" (pieces being the different designers embedded in this software), I was struck with a bit of a problem and decided to use a time proven methodology. The problem facing me is, you can design a rider, shell or frame.

It is quite possible none of those three pieces will be used in your current HPV project, or all of them could be. This problem has been addressed many times over the years and one common solution is one I'm adopting. If you are designing a frame, when you save, you'll be opted to save a frame file. If you're designing a shell, then you save a shell file. Likewise a rider file when building your rider's specs. You can load any of three types but loading a rider while designing a frame will have no apparent impact (the rider is imported but rider specs aren't displayed at the moment).

Also you can save/load a project file. A project file is a 3-line text file with up to 3 file names. The file names are the names of a Rider, Frame and Shell file. This will allow Users to easily switch riders or experiment with building a new frame for an existing shell, etc. etc.

Of course that's not how I started making saves/loads... since I had no idea I'd build a shell, frame and rider designer when I started this! Such is the nature of the software industry. In industry-speak it is called "requirement drift" or that stuff that comes out of the customer's mouth right after the phrase "That's exactly what I asked for, but what I really need is...".


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Grant-53
recumbent guru

USA
526 Posts

Posted - 12/19/2014 :  17:35:11  Show Profile  Reply with Quote
I sold auto parts for years. The three questions of customer service are:
May I help you?
What is it REALLY that you want?
So, what's it worth to you?
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/20/2014 :  17:41:00  Show Profile  Reply with Quote
quote:
Originally posted by Grant-53

I sold auto parts for years. The three questions of customer service are:
May I help you?
What is it REALLY that you want?
So, what's it worth to you?


All I want is a new LS-2 shortblock for $3!
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Grant-53
recumbent guru

USA
526 Posts

Posted - 12/21/2014 :  11:01:23  Show Profile  Reply with Quote
Add 3 zeros to the $3 or
I have 1/24 scale model kit of a Chaparral 2E.

Edited by - Grant-53 on 12/21/2014 11:03:21
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/22/2014 :  19:59:47  Show Profile  Reply with Quote
Roger that Grant. Was hoping to give a new msi for Christmas. Probably won't make it. I've had to dismantle the structure of this thing to allow splitting off the different designers. Lots of tedious changes to make the new save/load work properly. slowly beating it back into working again.
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/24/2014 :  10:42:58  Show Profile  Reply with Quote
Porting back and forth between the frame->shell designers was more of a challenge than I thought (isn't everything?). It goes well though. We have a "coder's term" called hard-coding. Hard coding is when you type in fixed value for something like ".125" instead of variable value Globals.Conversions.OneEigthInch. Its frame builder's equivalent is welding a seat in position only to later find the time to create an adjustable seat was well worth the flexibility it offered.

Math has been a tool all my life. I'm far too "out of shape" to do simultaneous systems of differential equations. Trig and linear algebra are easy enough that my rusty mechanics can get through especially with google looking over my shoulder. Nonetheless at points in this project there are places where SEVEN matrix arithmetic operations are cascaded together. One of these I fudged until it worked. Been fine allll this time until now. Finally had to dig down into code I haven't touched for a month, find my error and fix it. But now, at least the frame seems to port over correctly to the shell designer.

If I haven't killed anyone falling off their chair in boredom by this point, there has been a few humorous things happen. I built a standard weggie, and ported it over. The rider is still the old recumbent rider and the down tube of the weggie pierced him groin-high. I chuckled and thought something of the order, "That's some vindication to wives who say their husbands are too attached to their bicycles.".
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/29/2014 :  15:51:15  Show Profile  Reply with Quote
Just an update, still working on it every day, usually in 30-60 minute sessions 3-5 times a day. The frame designer is working well and the frame can be exported to the shell.

The project management routines seem to work pretty well now, I have written "configuration saves" many times during my coding career but this is the first time I've written project management saves (a project is a combination of a shell, a frame and a rider). The lines of code for a typical config save might be 10-20. This project save has ended up around 1000 lines of code, most of it a bit tedious to get working properly and (hopefully) intuitively.

Suffice it to say that the work continues. I've added a color selection to the shell (the frame had one built into it also). The shell is still a half-shell and no output yet.

What I don't have is hooking the rider to the new frame's crank and the rider designer is at its infancy, but the saga continues.

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Speedbiker
human power expert

USA
3701 Posts

Posted - 12/29/2014 :  17:40:24  Show Profile  Reply with Quote
This is an admirable project and you have done some serious work. But it seems your design concepts are totally your own. To me they look like ideas that were used before 2000, based on foils developed for the aircraft industry. Have you discussed the aerodynamic developments that have been developed since then for what are now state of the art human powered streamliners with any of the 5 (or so) top hpv designers? Since our Reynolds numbers are different from any other vehicle, I don't believe any of the designers of top vehicles are using establised NACA airfoil sections. Our designs have used custom, math based laminar cross sections.
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warren
human power expert

USA
6049 Posts

Posted - 12/29/2014 :  19:37:54  Show Profile  Visit warren's Homepage  Reply with Quote
The jury is still out as to what is the best shape for a 'liner. A well optimized shape that fits the rider and bike properly still seems more important than any specific mathematically derived vehicle shape. I agree that part of the problem is the side winds that are almost always present. The teams with the deep pockets should be doing the wind tunnel testing with the faired skewed a couple degrees because that's the real world conditions. Maybe version 3.21 will allow the top profile to be dragged like the side profile is to adjust it to whatever auto-lofted shape you want.
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/29/2014 :  21:00:48  Show Profile  Reply with Quote
Appreciate the commentary. You are correct that the design concepts are totally my own and I have not spoken with anyone about the "proper shape". As far as ideas used before 2000, that may be true but I can drag my rider box and tail box tugs around to the point that I cannot visually distinguish it from a Varna. Of course I am not capable of distinguishing "anything close" from a Varna but the resemblance can be made to be ... extremely close.

Essentially from the nose to the rider box (the fattest part) you can spin the shell along its long axis (like a skewer) and you will always see a 4-digit airfoil cross section up to the rider box. The tail area isn't so easy so, although I use the airfoil formulas to drive the closing shape (closing from the fat part to the tail) I was forced to make compromises on shape. I was a bit less worried about this as a long tail is really the only good solution for turbulent drag. Like the Chevrolet design team said defending the bluntness of the "butts" of one sports car. "We found there was nothing we could do. We had almost exactly the same drag no matter what we did to the turbulent rear area so why not just save the weight and chop it off?".

An important point about this is that I never set out to build a racer and have no intention of doing so now (for my own use). What got this started is "there just ain't no resource" out there for ribs to build a plug and that's what got this going. The rest of the work has been to support "somebody else's project other than my own".

Although the main idea of laminar is lowering the Reynolds number for the same overall length, the precision required is pretty high. I read that the thickness of the boundary layer is about the thickness of a thumbnail's thickness (about 0.5mm) and also read that for the laminar concept to achieve its desired intent, it must also be manufactured at least as tight as the boundary layer. This means that the shell shape must be precise, in absolute space, within 0.5mm. That seems pretty tight to me. Coupling that with the wind tunnel data that shows "laminar performs worse than standard" in all but near zero cross-winds and ... well anybody can use what they want but that does it for me.

As far as other shapes go. The formulas area is seriously ONE LINE of a monster that has grown to about 6000 lines of code at this writing. It is the interface, not the root formula that is hard. If anybody has a mathematical representation of the curve, I can incorporate it fairly easily. Tony mentioned that he had a mathematical representation of his shape. That would be harder but I have built the support tools to nearly port that in already. I can take a picture, reduce it to points, create Bezier control points (although S-spline might be easier) and reproduce that shape in any size and length. It would take some time to get it building the shell to that spec but that is doable. But ANY formula for shape should be pretty easy to inject into this.

The other nasty part is the ground clutter. We're all very ingrained that nose's must be "lower than center" to route low airstreams out of the pinch area between the road surface and the shell. Of course this software allows dragging it anywhere.

Best shape: Oh for sure for sure. A while back, I devoted a day to research using the internet and a real life pencil and paper. What I came up with was, when speaking of any decent shape, "no good design is better than reducing frontal area... period". The entire interface which allows a draggable rider box and animated rider is to support that essential concept. You can make this as tight as you like. Would like to add reporting that tells you just how much slop you have. Although paraphrased a bit, I remember Sam Whittingham saying, "Never tell a builder you have 5 mm's of space, he'll take it away.".

Oh btw, I would be happy to speak with anyone about this, really only "know" a few from right here on this forum. Have never even seen an HPV in person. All input is welcome good or bad.

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