Author Topic: free velomobile engineering plans  (Read 48961 times)

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dinges

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free velomobile engineering plans
« on: February 14, 2012, 03:08:54 PM »
For those interested in velomobiles, it may interest you to know that Alligt.nl (a major manufacturer of velomobiles) has made full engineering drawings available to the public, at no charge. And not of just any velomobile, but the Sunrider/Aerorider.

http://www.alligt.nl/bodies/allrider.html

(website is in Dutch, but Google-Translate usually is able to turn it into something that is almost, but not quite, entirely unlike English)



Thought it might interest the odd person here who's interested in purchasing or building a velomobile.

Building a velomobile has been on my agenda for a while as something 'to do someday', but in the near future it'll be more likely a bike trailer from GFRP I'll be making. Something along the lines as shown in the image below. Still just in the 'imagineering' phase though.





Hope to start building in a month or 2-3.
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

Bruce S

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Re: free velomobile engineering plans
« Reply #1 on: February 14, 2012, 04:48:54 PM »
dinges;
Interesting, here is an English website of the original Aerorider
http://www.aerorider.com/en/aerorider.html
They too are based in The Netherlands nice place and even nicer people, he and his dad built them all by hand.

We here at the office still have and ride it based 36Vac 800watt motor
Here's a blog about it , Jeff was the rider I did the battery/wiring stuff OH and Chili cook-off stuff he blogged about :-)
http://www.aerorider.blogspot.com/

Cheers;
Bruce S
« Last Edit: February 14, 2012, 04:51:45 PM by Bruce S »
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dinges

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Re: free velomobile engineering plans
« Reply #2 on: February 15, 2012, 01:01:41 AM »
The company you work at has an Aerorider? Very nice! If I had such a thing at work, I doubt much work would get out my hands.... would be too busy playing and riding with it.... ;D

Have you found out where the 'extra' button, without any apparent function, was for yet?

Velomobiles are still the exception here, but can be seen more and more on the roads. Mango's, Quests and Alleweders are the more common ones, but my personal favourite is the Versatile... the looks of that one  I find very attractive; not even mentioning the Rohloff hub whick makes this engineer's heart skip a few beats.



The Aerorider/Sunrider is very nice too. The cockpit of it reminds me of the gliders that I flew in an earlier life. It's much more sophisticated than the 'boat tub' velomobiles as the Quest etc.



Pretty luxurious cockpit, as far as velomobiles go.

Ah well. Am pretty happy with my Hurricane SWB 'bent, and have been for many years, but sooner or later it will see the companionship (competition?) of a velomobile. And if I have my way, it will be the Versatile....
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

Bruce S

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Re: free velomobile engineering plans
« Reply #3 on: February 15, 2012, 09:13:28 AM »
I asked the builder about the button when I traveled there for the pics in the blog-roll :-)
He said it was for "later" stuff  ;D
WE used it for an internal cooling unit that the rider could use during the summer months. Nothing like being in a fish bowl when its a 100F out there.

WE played a lot with it, I built the NiCd batt packs for it and have even tweaked them so its not a real issue anymore.
I've seen a few more around here lately, but when the ice gets to falling , they go into the garage...TOO many people sliding to take the little thing out.
I have replaced the first set of batt packs with a newer set that is more inline with a safer and more compact design.
If I were to do anything different, I would have requested they NOT bind the top and bottom halves, it would make working on it tons easier!! AND make the motor 48V instead of 36V, that would make climbing the hills around here a bit quicker, however pedaling does solve that issue.
Charging them from solar using GHURD's solar controller really does help too!
Cheers
Bruce S
PS I like your sig!! Reminds me of DUNE
A kind word often goes unsaid BUT never goes unheard

Simen

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Re: free velomobile engineering plans
« Reply #4 on: February 15, 2012, 10:44:27 AM »
Bruce:
Dune and tesseract?!

My first experience (live experience?! ) with tesseract was when i was aboard the Andromeda...
http://andromeda.wikia.com/wiki/Tesseract

:D :D :D
I will accept the rules that you feel necessary to your freedom. I am free, no matter what rules surround me. If I find them tolerable, I tolerate them; if I find them too obnoxious, I break them. I am free because I know that I alone am morally responsible for everything I do. - (R. A. Heinlein)

zap

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Re: free velomobile engineering plans
« Reply #5 on: February 15, 2012, 11:48:41 AM »
dinges, how do you plan on making the trailer?  You mention GFRP... are you going to mold it?

Bruce S

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Re: free velomobile engineering plans
« Reply #6 on: February 15, 2012, 02:18:33 PM »
Bruce:
Dune and tesseract?!

My first experience (live experience?! ) with tesseract was when i was aboard the Andromeda...
http://andromeda.wikia.com/wiki/Tesseract

:D :D :D
WOW shows our age huh  ;D, that was a pretty good show after Hercules went the way of Xena.
Space folders in DUNE!

Dinges::Sorry for the tangent.
Bruce S
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dinges

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Re: free velomobile engineering plans
« Reply #7 on: February 15, 2012, 05:59:01 PM »
Bruce: don't worry about any tangents. Even if they're not entirely on-topic, I find these usually the most interesting.

Zap: the plan is to glue sheets of extruded styrofoam (Roofmate or similar) to eachother to make a block of 600x900x450 mm of styrofoam; use a hotwire cutter to cut it into its general shape, and then to manually sand the round edges (radius of 50 mm, checking manually with a cardboard template).

The trailer is pretty squarish, but not so square as my previous bicycle trailer (which I call 'coffin-on-wheels' for obvious reasons):



I want something that looks a bit more elegant and is more aerodynamic, and sits lower (better balance, less sensitive to crosswinds). But most importantly is that it must be visually pleasing, and I've so far never seen a bicycle trailer that is, not even the very expensive ones. They all look a bit hacked to me (including my own coffin-on-wheels), despite the fact that the build quality isn't bad - it just doesn't look right, IMO. Unlike motorbikes, where one can find very elegant trailers.

By using GFRP (epoxy), one is pretty free in the shapes you can make, including very curvy/organic/female shapes, with double-curvatures, but I find that not very visually pleasing, so have opted for a more squarish look, whilst still being reasonably aerodynamic (as far as a trailer can be aerodynamic, anyway).

The plug will be glassed with glass cloth and epoxy, after which the core will be removed by chipping it out after the lid has been sawed off. Then comes the sanding, filling and painting.

I intend to cover the inside of the box with a liner, something similar as used in the interior of cars, to reduce noise and rattling of cargo.

Still puzzling about how to mount the wheels (40-406 size, same as bike), but will probably make a simple aluminium frame where the two wheels attach to and to which the box attaches; don't think I can get away with mounting the wheels straight to the box, even with reinforcements in place, but we'll see about that part later.

Hope that clarifies it.
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

Bruce S

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Re: free velomobile engineering plans
« Reply #8 on: February 16, 2012, 09:09:57 AM »
Dinges;
Nice trailer. One of the tricks you could use to bring the new trailer lower would be a drop axle, similar to the trucks of to late 40s & 50s. This would give you the strength along with a bit extra lower in height. Even channel (boxed) tubing could be used cutting 45 degree angles and using lengths to obtain the lower stance.
Looking forward to see the results.
Cheers;
Bruce S
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dinges

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Re: free velomobile engineering plans
« Reply #9 on: February 16, 2012, 09:43:59 AM »
Bruce, had to google that term (drop axle), wasn't familiar with it, but yes, something along those lines was what I had in mind for the trailer. Probably will mount the cross bar on the inside of the box, even if that means losing the flat bed on the inside.

Slowly beginning on building the tools for building the trailer (hotwire cutter and straight sanding thingies). The actual building will have to wait till temperatures rise a bit more; should also give me some extra time to figure out a few of the smaller details of it all. But as it stands now, the looks are likely to change very little, I'm satisfied with that part.
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

Simen

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Re: free velomobile engineering plans
« Reply #10 on: February 17, 2012, 02:20:09 AM »
Dinges; what's the weight of your trailer as it is now?
I have a simpler trailer without the box, which i'm planning on 'boxing it in', and put 3 solar panels on as a lid, but i'm a bit worried about the balance and weight... :-\



(The motor on the bike are 36V, 750W, and the battery in the pic are 36V, 16Ah LiMn. The battery have now been swapped out with a 36V, 20Ah LiFePo pack.)

Bruce; ofcourse, i guess they tesseract when they folds space in Dune; that's what Spice are for... ;) Andromeda was a good show; another one was Farscape, though a bit crazier... :D
They don't make them like that anymore... :(

:D
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dinges

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Re: free velomobile engineering plans
« Reply #11 on: February 17, 2012, 03:23:26 AM »
Dinges; what's the weight of your trailer as it is now?

You mean the wooden box trailer? I don't know, haven't ever measured it - will do so this weekend and report back to you.

Weight isn't much of an issue here in Flatland; it only matters when you need to climb many hills, or when accelerating or stopping. That's why it hasn't ever occurred to me to weigh it, to be honest.

Quote
I have a simpler trailer without the box, which i'm planning on 'boxing it in', and put 3 solar panels on as a lid, but i'm a bit worried about the balance and weight... :-\

I assume to charge the batteries? Aren't you worried about damage to the glass PV panels in use? I know I would be....

I don't think you need to worry much about balance, provided you don't build the box too high; it appears your trailer is using 16" wheels so it sits pretty low, unlike mine which uses 20" wheels for logistical reasons - I'd actually prefer 18" or perhaps even 16"....

In the mean time, I think I've figured out how to install the wheels; make a stiffening bridge out of 8mm plywood, laminate it in. That should stiffen things up a bit:



The rest of the bottom will probably be a sandwich construction, with a (10 mm?) layer of roofmate covered with a few layers of glass cloth. That should give me both a stiff and flat loadbed. The sidewalls and lid will probably be stiffened with trianguar strips of roofmate which will be covered in glass (sandwich construction).

Should create a light yet strong and stiff box, I think.

Now, if I could figure out how to build a tesseract..... so I can store stuff in that 4th dimension.....
« Last Edit: February 17, 2012, 03:27:28 AM by dinges »
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Simen

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Re: free velomobile engineering plans
« Reply #12 on: February 17, 2012, 03:55:23 AM »
Quote
I assume to charge the batteries? Aren't you worried about damage to the glass PV panels in use? I know I would be....

I haven't started worrying about breaking panels - Yet... ;) But i probably will once they're mounted... ???

Yes, for putting a little power into the cells when parked. I'm planning on 3 15-20W panels, depending on size. The battery pack consist of 2p12s 3.3V/10Ah LiFePo cells. I'm going to use 3 separate solar controllers connected to each 4s2p cell group. Now, Lithium cells are a bit demanding on how they're treated, but LiFePo cells will have max 3.65V charging voltage, and that makes 14.6V for 4s cells, and the solar controllers delivers max 14.4V, so i think that will work out rather ok. :)
I will accept the rules that you feel necessary to your freedom. I am free, no matter what rules surround me. If I find them tolerable, I tolerate them; if I find them too obnoxious, I break them. I am free because I know that I alone am morally responsible for everything I do. - (R. A. Heinlein)

Bruce S

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Re: free velomobile engineering plans
« Reply #13 on: February 17, 2012, 09:43:42 AM »
Dinges;
Using 8mm plywood, then laminate it to help stiffen it up?  I would think by the time you do all that it will be above the weight of boxed steel with 1/2 the load bearing ability.

Simen:
Farscape was on the PBS channel here before the digital conversion, a great series Firefly was/is another one.
You will be pleasantly surprised at how robust the small solar panels can be. The smaller 10 and 17 watt panels Rich installed in the Philippines are durable enough to be "trekked" across the mountains in backpacks Rice bags and sustained no problems.

If they stood up to this type of handling on top of a trailer should be NO problem. You could go the route of the foldables and have them inlaid.

 
Just a thought;
Bruce S
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zap

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Re: free velomobile engineering plans
« Reply #14 on: February 17, 2012, 09:45:24 AM »
Dinges,
I kinda like the coffin look... it reminds me of my trailer.

Be careful of going to low with the axle.  I used an old Burley frame for Woody and reversed the axle mount from below to on top.
I now have to be extra careful of straight curbs that are higher than 4 or so inches but having it under slung by that much makes for a very stable trailer... I've never worried about flipping it.

Looking forward to some progress on yours.

REdiculous

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Re: free velomobile engineering plans
« Reply #15 on: February 17, 2012, 01:12:57 PM »
Neat.

I like that 2 wheel trailers are extra stable when stopped, but I hate the way they handle and drag on the bike compared to a bob trailer..

I'm doing a bob type trailer for my pocket bike. I'll probably go w/ a 10" wheel to keep wheel size consistent. I've got a couple rigid plastic boxes that sit low in the trailer frame, which is made from old shopping cart tubes. I hope to integrate a tent and may end up adding solar and a mini windmill. The bike has a 1kw inverter to power the motor so there'll be wall-power convenience when camping. Clearance could be an issue, but it's not meant for curb hopping - it just needs to make it over little speed bumps and such.

Fun stuff.
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dinges

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Re: free velomobile engineering plans
« Reply #16 on: February 18, 2012, 12:56:47 AM »
Using 8mm plywood, then laminate it to help stiffen it up?  I would think by the time you do all that it will be above the weight of boxed steel with 1/2 the load bearing ability.

Little bits of plywood and a layer or two of glasscloth & epoxy over it? It's nearly weightless, in my opinion....

I'm not worried about load-bearing ability - the thing will be plenty strong - it is rigidity that's my main concern. But relatively easy to make the box stiffer, if it turns out to be too flexible.

Besides, weight shouldn't be something to worry about too much with a trailer. I mean, why save 0.5-1kg in weight there when, in use, the thing will be loaded with many kilograms of stuff.... (I know, a kilogram is still  kilogram.... and every little bit matters.... and it's always the last straw that broke the camel's back....); doesn't make sense to me to go through great lengths to reduce weight of a bike trailer. Doesn't mean it has to be built to withstand an earthquake either, of course. You've still got to haul that thing around by your own power, so some prudence in limiting weight is in order.... As always, lots of compromises to be made. That's the nice thing about building it yourself from scratch, for your own use (as opposed to building it for an 'average' customer, with different people having very different demands and requirements).

Oh, BTW... the 'bent that will be the tractor.... it's not exactly a light beast either.... last time I weighed it, it was at 24.5 kg (54 lbs); that's including the things that I always carry with me, some tools, etc.; I occasionally get some fun out of mentioning that weight to roadies, watch them gasp for air.... :D ... and then accelerate and let them eat dust.

Again, this is Flatland.... weight isn't the problem here it would be in e.g. San Francisco. It's the blasted wind that's my enemy. And even in windless conditions, riding with an, err, 'aerodynamically sub-optimal' trailer behind a bike isn't something you do for fun or when you want to go fast.... It does make for some good exercise though.... :P

Anyway, I think my plan of using plywood & GFRP over it will be the strongest and most rigid solution on a by-weight basis, compared to boxed steel. The thing that has me more worried now are the stainless steel flanges that will be mounted to the box and will hold the wheel axles.... as these will actually be relatively heavy.

REdiculous: yeah, riding a trailer isn't something you do for fun or if you can somehow avoid it. Necessary evil, I suppose.

BTW, a worry with PV panels on a trailer to me would also be theft and vandalism. On occasion, people here seem to get joy, pleasure and satisfaction out of destroying other people's property. Wouldn't be the first time people would smash other people's PV panels just for fun.

People.... will never understand them, I think.
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

ruddycrazy

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Re: free velomobile engineering plans
« Reply #17 on: February 18, 2012, 01:38:20 AM »
G'day Dinges :P,
                         First mate sworry about that vaseline quote.......... I do hope your over it.....

Now as far as people stealing I'm sure you made a DIY tig so just spot the nuts.... end of story.

I do have to say it is great you are posting again so could I offer a personal invite to the new anotherpower forum. I'm you and Oztules will get back to your old tricks.

Regards Bryan

Simen

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Re: free velomobile engineering plans
« Reply #18 on: February 18, 2012, 02:13:29 AM »
Now, theft and vandalism i haven't thought about... ??? The motor controller do have an alarm that triggers easily, with a loud alarm sound, and then the controller electronically blocks the wheel, making it impossible to pedal away... ;)

There are plenty of hills around here, so weight are a bit concern to me; not that i'm afraid to break out unnecessary sweat, but it does reduce battery capacity... :D I'm not sure, but i think my trailer weighs around 9kg as it is.
I will accept the rules that you feel necessary to your freedom. I am free, no matter what rules surround me. If I find them tolerable, I tolerate them; if I find them too obnoxious, I break them. I am free because I know that I alone am morally responsible for everything I do. - (R. A. Heinlein)

dinges

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Re: free velomobile engineering plans
« Reply #19 on: February 18, 2012, 05:42:49 AM »
Bryan, no worries; I thought we had settled that matter long ago anyway.

And still have to finish my 7.5 kW motorconversion; the rotor is sitting in its cradle in a fully closed cardboard box in the shed, waiting for me to rewind the stator. For some strange reason, that box seems to attract all the chips that fly around.... perhaps something to do with those 36 cubic inch of neos on it? Will probably start working on it this spring, rewinding the stator. The original plan was to work on it this winter, but it was just too cold in there.

Simen, as promised, I put the trailer on the weighing scale; it weighs in at 15.5 kg. Some more details: the wooden box is 540x800x350 mm (WxLxH), made of 8 mm plywood (non-waterproof grade... I'd use waterproof if I were to build it again). Some more build details are here:

https://picasaweb.google.com/motorconversion/BicycleTrailer


I agree with you, in hilly/mountainous Norway you probably want to pay some attention to weight.

Weight isn't unreasonable for my needs and local situation, but it's the aerodynamic drag that is, well, .... a drag.
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

zap

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Re: free velomobile engineering plans
« Reply #20 on: February 18, 2012, 11:56:26 AM »
I like that 2 wheel trailers are extra stable when stopped, but I hate the way they handle and drag on the bike compared to a bob trailer..

I don't have any time under my belt pulling a bob but I pulled an old Bell steel trailer around for awhile.  The only problem I ever had was cutting a corner too close and catching one tire on a pretty big landscape boulder... flipping the trailer on it's side.

Maybe I lucked out and got everything close on the build or maybe it's just the low center of gravity... but I've had Woody up close to 30mph and it was a non-event.
Under power it's a little odd when you hit a good sized hole or a bump but whether he's pushing me or I'm pulling him... whether he's got a 30 pound load or groceries or he's empty... all in all... I'd say the ride is pretty benign.

Since I wanted Woody to be a shopping cart also, two wheels made much more sense.
The locomotion 'guts' obviously add weight but I've pulled him quite a few miles without him adding a single horse and it's really no big deal.

REdiculous

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Re: free velomobile engineering plans
« Reply #21 on: February 18, 2012, 02:19:07 PM »
Maybe I was unlucky but I've only pulled one 2 wheel trailer for any kind of distance and I hated every blasted second. What I noticed is it tended to 'walk'. The left side was more rigidly attached, but still not actually rigid, so that side seemed to get pulled forward first and then the right side would catch up, resulting in a sort of push/pull on the bike. Also two wheels vs one is a power/weight (and efficiency) thing.

If you need to carry excessively large and heavy loads then the extra stability of the 2nd wheel is worth it, otherwise I'd rather pull a more efficient bob type. If I had to pull a 2 wheel trailer I'd want to attach it better than "they" do because being able to pull the bike forward 4" before the trailer starts moving is no good. That's the problem I've always had w/ those and I know it doesn't have to be an issue.

Still, there's the efficiency argument. Sliding around corners on two wheels has to be less efficient by far. A bob trailer will lean and track around some crazy-sharp corners before the wheel slides out.

neat projects tho.
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dinges

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Re: free velomobile engineering plans
« Reply #22 on: February 26, 2012, 03:05:22 PM »
After a bit more of messing around with CAD software modeling a trailer, and looking for suitable mold material (I wanted extruded styrofoam (e.g. Roofmate) but the price of just the foam was more than the entire budget available for the trailer.... and that for something that won't even be a physical part of the end product.... so ended up with expanded styrofoam - not ideal, but doable) I decided on a smaller trailer of 500x850x440 mm.

I've also changed the wheels to 16" ones.







The biggest work is making all the tools - the actual cutting of the styrofoam block into shape is the easy part. Probably also has to do with the convenience of having a versatile power supply that has no trouble heating up a 1.2 mm stainless wire of the profile knife to a high enough temperature to cut styrofoam.... 9A in my case..... the long straight hotwires of NiCr wire are happy with 2A - the PSU does it all, at the turn of a button.

Next step is the glassing. Will be placing an order for epoxy and glasscloth soon, as I only have a few m^2 left and only .5 kg of epoxy.
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

taylorp035

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Re: free velomobile engineering plans
« Reply #23 on: February 26, 2012, 05:20:57 PM »
Cool!  Before I saw your homemade hot wire, I would of sworn it was CNC cut  :D

I just carbon fibered my car last Friday... should be dry by now.   Are you going to use a vacuum bag?

dinges

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Re: free velomobile engineering plans
« Reply #24 on: February 28, 2012, 07:40:07 AM »
Are you going to use a vacuum bag?

No, just hand lay-up without vacuum bagging.

The shaping of the box isn't hard; it's relatively squarish so mostly straight cuts with a hotwire. The hardest part were the wheel wells but with a simple shaped tool that was easy too - just as simple as drawing a circle on paper with a pair of compasses :D



Small pieces of plywood with a hole were epoxied on the box, to serve as the pivot point for the profile hot knife:





What was left over in the middle was removed manually with a straight hotwire and some sanding.



Finally, the outer fillets of the wheel wells were made with this little tool:





Using a hotwire knife beats sanding by a large margin. I rather spend one hour making a hotwire tool than do 10 minutes of sanding styrofoam....

At the moment trying to figure out how many layers of which glass cloth I should use. 3 layers of 80 gr/m² is definitely much too little. A test sample of 4 layers of 280 gr/m² is now curing - hopefully that'll be enough.

Problem, as expected is not the strength but rigidity/stiffness of the box. That's where the stringers will have to come into play though.

Surface area of the box is 1.63 m². So 4 layers of 280 gr/m² would mean 1.8 kg of glass, with roughly a similar amount of epoxy for a total weight of, say, 3.6 kg (without any extra reinforcements of the load bed or side walls - just the skin of the box).

If anyone has any suggestions regarding type of glass cloth and number of layers.... as I don't have the experience to make even a ballpark guess.... I'd be listening.
« Last Edit: February 28, 2012, 07:45:41 AM by dinges »
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

ghurd

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Re: free velomobile engineering plans
« Reply #25 on: February 28, 2012, 09:17:25 AM »
I don't see the gas cap.
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dinges

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Re: free velomobile engineering plans
« Reply #26 on: February 28, 2012, 09:53:13 AM »
Quote from: Ghurd
I don't see the gas cap.

Very observant of you. It's part of my cunning scheme.... a bike that can travel faster than a car (or even anything else invented so far by man!) and that needs no petrol; but don't spill the beans yet or a black car with tinted windows and with some men in black wearing sunglasses may come and take me for a ride.... Big Oil and the gov't don't want people like me thinking out of the box (or gas tank)! It's me patents they're after, and my brain - a guy with a brain is a dangerous thing to governments....

But I see there's no fooling you. Actually, that trailer box isn't going to be an empty box... that's just a ploy to keep Big Oil off my back during the development phase. Secretly hidden from view inside the box there will be two contraptions... one is a motor, the other one is a generator. That's also the reason that there are two (not one!) wheels.... one wheel will be driven by the motor.... but.... (here comes the clever bit!) the other wheel will be *driving* the generator. The generator is connected with 3 wires (for more efficient 3-phase of course) to the motor.... But I can't give you more details because I want to patent my idea - I'm sure you'll understand.

But it's very simple really.... the faster the trailer goes, the more energy the generator generates, and the more faster it will drive the motor... the more faster the bike will go, and the more energy the generator will generate.... ad infinitum! I expect the only limitation to my travelling speed will be c (unless Einstein was wrong, in which case Dinges may well become the Chuck-Yeager-of-faster-than-light-travel).

It only needs pedaling in the beginning, to jump start the process. After that you can just sit back and enjoy the scenery as it whizzes by.

Which reminds me that I will also have to install some good brakes on it....

I spent a lot of time and brainpower thinking about this and the idea is just so obvious that the only reason I can think of that no one else tried this is because the gov't and Big Oil are keeping this obvious solution to the impending energy crisis well-hidden....

So that's the reason there's no gas cap, though I may add one just for show - just to keep the men-in-black and the oil sheiks off my back....
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

ghurd

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Re: free velomobile engineering plans
« Reply #27 on: March 04, 2012, 11:46:54 PM »
 8)

The foam shaping is spectacular.  Like Taylor siad, CNC quality work.

WiFi is slow today.  My grounded AL foil hat is messing up the signal.
(AL foil hats must be grounded to keep Will Smith away... and so far he has not been here... so it works!)
G-
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dinges

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Re: free velomobile engineering plans
« Reply #28 on: March 05, 2012, 08:11:25 AM »
Quote from: Ghurd
My grounded AL foil hat is messing up the signal. (AL foil hats must be grounded to keep Will Smith away... and so far he has not been here... so it works!)

The problem with aluminium foil as hat material is that it only keeps the electromagnetic waves out, not the magnetic fields. Personally I swear by mu metal. Or, in a pinch, you could even use old motor or transformer laminations.

Talking of laminations.... have to stash up on glass cloth before I can continue with the trailer project. I did however invest in 5.5 kg of epoxy....

BTW, the last time I heard my gas cap click was in november.... Have nearly forgotten how it sounds or how many clicks there were. Which is good, because every time I pass a gas station the prices nearly give me a cardiac arrest. Fortunately my bike is happy with nothing more than some air in its tyres....

Peter (<-- wonders if building a trailer makes him trailer trash?)
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

DamonHD

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Re: free velomobile engineering plans
« Reply #29 on: March 05, 2012, 11:31:25 AM »
Hey G, is your metal hat keeping away elephants too?  B^>

Rgds

Damon

PS. Go with the mu-metal, I say.  And as an ex-biology tutor of mine said, a whole-body condom for good measure.
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zap

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Re: free velomobile engineering plans
« Reply #30 on: March 08, 2012, 11:31:45 PM »
That foam does look pretty nice... but
Quote
It only needs pedaling in the beginning, to jump start the process. After that you can just sit back and enjoy the scenery as it whizzes by.
???

I recently saw a commercially produced push trailer that's made just up the road in Ft. Collins.
http://www.ridekick.com/


dinges

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Re: free velomobile engineering plans
« Reply #31 on: March 09, 2012, 04:16:16 AM »
That foam does look pretty nice... but
Quote
It only needs pedaling in the beginning, to jump start the process. After that you can just sit back and enjoy the scenery as it whizzes by.
???

Why that doubtful look? :P  ;)

Gotta think outside the box man!

But yeah, better stop it now, before people actually start taking it seriously and start spending time and effort building such a thing.

Quote
I recently saw a commercially produced push trailer that's made just up the road in Ft. Collins.
http://www.ridekick.com/



I've read about it too. The advantage is that there's no weight penalty on the bike; you only take the trailer with you when you need it.

One thing I wonder about though is whether the trailer wheels don't easily spin when pushing, as there's little weight on them.

Other than that, may well be a solution for some people. My mother got herself a pedal-assist bike about two years ago and to her it makes all the difference - it has increased her action radius from about 10 km (enough for errands) to about 50 km (enough to visit more distant family and friends). It's pedal assist, so no pedaling means no assist. 'Only' 250W motor (legal limit here) and 11Ah battery, max. assisted speed is 25 km/h....

I've never  been a fan of electric assist myself for various reasons but man... riding her bike, I sure could get used to it!

So far she has about 5000 km on it, for 4-5 euro worth of electricity. It's getting to be a rarity here to see people 'of a certain age' who do *not* ride a pedal assist....
“Research is what I'm doing when I don't know what I'm doing.” (W. von Braun)

Bruce S

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Re: free velomobile engineering plans
« Reply #32 on: March 09, 2012, 08:33:53 AM »
Where was to trailer when I was trying to figure out where else to stuff more batteries into the e-scooter?
Nice looking, a bit pricy for me but sure would make adding an extra bank easy enough, and a place to keep groceries dry too!
Cool
Cheers
Bruce S
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