Instructables
Picture of Velomobile Three Seat Electric Car
tonbrella copy.jpg
Environmentalist? Give this a try!

The problem: Need exercise and local transportation
The first solution: Electric bike kit! (excellent parts from ebikes.ca)

The new problem: It rains here. A lot.
The second solution: A zero emission vehicle with a roof.

The plan is to make a car that is light weight and pedal powered with electric and solar assist.


For now this is a build log and collection of messy notes. I'll add more over the next few days until school starts again. Feel free to subscribe and check back in the spring (of 2013) when I hope to have the front wheels on.

Minirant: I was trying to sell my neighbour on electric bikes and she said "It rains a lot here". Which is true and it got me thinking; is it crazy that in our culture we use two tons of steel as an umbrella and call it normal? A tonbrella as it were. This vehicle is my first attempt at a more practical solution to the rain issue.

Step 1: Prior Art

Picture of Prior Art
VM rear 3quarter.jpg
Fantom2sits.jpg
vm rear.JPG
At Maker Faire 2012 in Vancouver I saw a couple electric cars. One was a Porsche (converted by my childhood friend it turns out). The other was made of door skin and a lot cheaper to make; plus it can go 60km/h 37mph.

This plywood car was called the Fauchet = faux + Mochet
Georges Mochet made pedal powered micro cars in the 1940~50s.

Mr. 1JohnFoster (from http://endless-sphere.com/forums/viewtopic.php?f=2&t=25315&start=30) made his Fauchet electric car out of 1/8" plywood using a stitch and glue boat building technique.  http://fauchet.tripod.com/



Stitch-and-glue seems like a construction method that is quite useful: it requires no specialized tools, no mold (unlike fiberglass), little skill/experience, cheap materials. We'll find out shortly.

(Will add image credits once the notation system is fixed)

Step 2: Measure Driver

Picture of Measure Driver
Custom made for a person like this:
inseam: 70cm = 27 1/2"
thigh ground to crotch barefoot 34 = 13.4"
shin ground to knee bump 43 = 17"
torso sitting ground to shoulder bone 56 = 22"
arm shoulder bone to palm fingers up, palm forward 56 = 22"
hips 41 = 16"

 
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Ganhaar5 months ago

A few comments about velomobile front geometry...

1. Bicycle wheels are designed for minimal side load

2. Velomobiles can develop greater side loads than a bicycle

3. Side loads on the wheel can be reduced a little with a small inward camber

4. Smaller bike wheels (eg20") handle side loads better than larger wheels

To see some examples of steering geometries, check out Electrathon in the USA, EV Challenge in Australia and Greenpower in the UK. These are all competitions for modern velomobiles. Most will have zero or inward camber on the front wheels and greenpower rules even goes so far as to restrict wheels to max 20".

I have been competing for several years and have seen only one car have a wheel collapse (27" wheel) in that time, but I have also seen some college teams put together some complex rigs with tilting wheels to allow them to use large wheels and avoid wheel side loads.

I would recommend stick with 20" bmx wheels and find hubs with the largest axel that you can, at least 16mm and you should be fine.

I would also consider a swing axel for suspension as an alternative to a macpherson strut or sliding hub. Swing axels had a brief history in motorsport between the live axel and the development of wishbone suspensions. Swing axels came at a time when wheels were very narrow but when tyres started to get wider suspensions such as wishbones that could better control wheel geometry were developed. A swing axel is still well suited (simple and easy to fabricate) to skinny bike wheels.

regards

Wayne

I feel it necessary to correct you, sir. Although smaller bike wheels do take weight from the side more effectively. However, it is untrue that having negative camber will improve this problem. Either straight wheel or even slightly positive camber will help with handling and side weight management.
PaddyO663 months ago

"Brakes" is the correct spelling. Avid BB-5s are a nice choice of brakes, btw. Simple, powerful, good quality pads available for them, so in the long run, economical. Great instructable! Very informative and inspirational!

wgreenbough11 months ago
I'm sorry, but I have to speak up and say that the suspension design for this velocar is just plain wrong and dangerous. Velocars and their history is a passion of mine and i'm fortunate enough to have French articles written in the late 1940's on how to build a velocar in the home workshop using basic tools. I'm hoping that it's possible to post an image or an image link as I have a drawing taken from one of these articles that shows how the suspension should be laid out .

VelocarSuspension.jpeg

This diagram shows the kingpin axis vertical and the wheel inclined to reduce scrub radius. You can achieve the same with a wheel cambered inward instead of outward as in this diagram and an angled kingpin. I don't know why the old velomobiles had a vertical kingpin and wheels cambered outward.

snotty (author)  wgreenbough11 months ago
Hi, thanks for the heads up. If possible, could you give us some more details about your take on suspensions? I've put in a lot of effort trying to find the simplest practical solution and it seems to be working so far but I'm all ears.

From first glance it seems to me that the diagram you posted would work fine for a vehicle going straight but I'd be too chicken to try it with a bicycle wheel with inward camber since it would feel a lot of lateral force and might fold in half.
wgreenbough snotty11 months ago
Hello snotty, the steering geometry in the diagram is correct for a velocar and works well having been tested thoroughly by French citizens in need of transport during the war years. Bicycle wheels don't actually fold up that easily unless you're in the habit of trying to slide into corners much too fast. Provided the gauge of the spokes you've chosen for your wheel are adequate for the job, they are properly tensioned and the wheels are true you won't have any problems. I grew up in a family where my Dad and my brothers were tradesmen in the motor and metal trades and because I was interested in vehicles and how machinery worked I was taught how to weld as well as repair my own car. With cars being repaired and rebuilt as a constant part of the background as I was growing up I have a good eye for what is right and what is wrong when it comes to vehicles and I'm sorry for having to say this but having that degree of negative camber on your velocar's wheels isn't safe and isn't good engineering.
Positive camber as in the diagram with minimal or no scrub radius at the tyre's contact point with the road is the safest and most simple layout for a velocar.
This geometry can be easily seen in this photograph of a Mochet Velocar.

 


VelocarSuspension1a.jpegmochet-velocar-2.jpg
Horay! It rolls! How does the steering & front suspension work?
snotty (author)  604johnfoster1 year ago
How does the front steering and suspension work? In a nutshell it works OK. The suspension is based on regular MacPherson strut design but there are no anti roll bars or anything complex like that.

The steering is a simple tie rod between the wheels and a push-pull cable steering system for a boat.
Brilliant Tomoe, I like the layered plywood approach. Much more elegant than my multi-material methods. I still haven't finished reinforcing mine in these areas, because of the complication of laminating the wood strips I have.
snotty (author)  604johnfoster1 year ago
Yes! This new magnet clamping method opens up a lot of new possibilities for laminating doorskin.
Lokisgodhi1 year ago
As for the front suspension, you could try looking at the sliding pillar design used on the old three wheel Morgan motorcycle/cyclecars.
snotty (author)  Lokisgodhi1 year ago
Oh neat! Do you mean like this picture? I found some that seem to use a regular double whishbone. I wonder how that sliding pillar would affect steering when braking especially when turning. With the vertical pillar, it seems like there could be steering/pull issues... but I suppose it worked for them. Any thoughts?
morgan.gif
Every design is a compromised - otimised between objectivity and outcome.

What is great in the straits is crap in the corners and vis versa....

Etc.

The loads are small, the speeds are low, the roads are smooth, so a little bit of suspension is nice.
Yeah, like that.

It's a simple design but fairly rugged. It also fits in with the period when cyclecars were common.

Here's some more info.

http://en.wikipedia.org/wiki/Sliding_pillar_suspension

http://upload.wikimedia.org/wikipedia/commons/9/93/MorganSuspension.jpg

Another vehicle to look at is the Velorex. A post war Czech built three wheeler made of a tubular steel frame covered with vinyl.

http://en.wikipedia.org/wiki/Velorex

http://upload.wikimedia.org/wikipedia/commons/a/a9/Velorex.jpg

Lokisgodhi1 year ago
As for the front suspension, you could try looking at the sliding pillar design used on the old three wheel Morgan motorcycle/cyclecars.
Ooo, that does look hard. I did my wheelwell in cardboard 1st, then transferred it to plywood. Maybe that's cheating on your CAD 1st process. Mine also tapers to the top, more comfy for a narrow bum. Would be pretty tippy with a wide bum in the rumble seat. Also it makes it easier to get bags of stuff in & out of the back. But I guess the taper would be even harder in CAD :( Good luck! I'm building a center stand for mine now, of bamboo, inspired by you. It's been really annoying trying to work on the drivetrain with it just held up by bits of wood and it falling down on my head all the time.
snotty (author)  604johnfoster1 year ago
CAD=Cardboard Aided Design.

There might be a solution to the drivetrain falling on your head: a gobo stand. These are possibly the most versatile tools in the film industry. A gobo stand is typically a stand with feet and a telescopic mast and a meter-long metal arm with grippers. A mafer clamp or something similar will help grasp oddly shaped objects. In my old career I used these to hold many things in almost any position. With a few 20lb sandbags on the stand's feet you can hold heavy objects in all sorts of odd angles and heights. They cost about $200 and a film rental house will probably rent them for ~$15/day.

Hopefully I'll be at Maker Faire again this year. Maybe I'll see you there :)
Good progress! I like the hemp&pva innovation. Strut tops anchored to the top vertex is also a good idea. Stronger floor plywood good too, although I think 1/2" is overkill.
I'm not so enthusiastic about the canted front wheels though - will be better for loading on the outside wheel in a turn, but even worse for the inside wheel. The inside still bears weight - you won't transfer really all that much weight, even at the limit of traction.
Also to help keep the CG closer to the front wheels I put the battery pack in the nose, doesn't look like you have much space, or are you going pedal only?

May kWh ride was fun. Zenon had his "future mobile" and I had my "retro mobile". +~10 other 2 wheelers.
Later, John
a1auto1 year ago
Awesome idea & nice design! (Love the pic too!)
20mm hollow axle hubs. 20mm is definitely strong enough. The problem is the narrow width between flanges: It's OK for the vertical load when used on a two wheel vehicle, but not nearly strong enough for the side loads you would get cornering at speed. To make it stronger you could make the hub wider by cutting it in half and putting pipe in the middle to spread the flanges out. But then you run into the limitations of the flange and spoke strength. Or use smaller wheels - one of the reasons most velomobiles use 20" or 16" wheels. BMX 14mm solid axle hubs are also strong enough for single sided, at least for 1 person. They can also come made for heavier gauge spokes and higher spoke counts. And you you might as well get built 20" wheels. Don't know if they come with discs these days.
Hi Snotty,
I'd like to visit your workshop when you have time to start. Also I have a lot of bike & other parts if you want to come over & grab some junk. I (& the Fauchet) live on Powell near Main, DTES Vancouver. I did use bike forks as struts - the black foam at the Maker Faire was just to hold it up because the air seals leak. Not sure about the side loads; since I have 26" wheels on narrow hubs I corner very slowly. We will have to have a race when you get on the road! Or at least a rally - I'm organizing the May kWh ride. I want to see your improvement on my pound-a-brella.
Later,
John
snotty (author)  604johnfoster1 year ago
I'm curious about the front wheels you used. Were they standard bike hubs or where they specifically made to be supported on one side only? I'd like to use standard bike hubs but I've always assumed they's bust the axle off.
snotty (author)  604johnfoster1 year ago
Sure thing! I'm deep in school and my workshop is a day's travel and many ferries away so there won't be much action for a while. I can probably nip by to your shop some time during spring break (Feb 8th 2013). Feel free to PM me with the details. Maybe we can take your Fauchet on a cruse to Justin's warehouse :)
Hi i was thinking about making a mini tractor from the instructable Mini tractor from go kart parts and i was wondering would it be easier to make it with a gasoline engine or eletric engine.

If you would like to donate to this project you can send a donation with paypal to parkhigley6@gmail.com Thank you for reading
snotty (author)  masterfireeater1 year ago
For me electric systems are way more reliable and cheaper in the long run. My teacher made an electric tractor and said it was cost effective since non-electric tractors waste a lot of fuel by idling. Lead acid batteries were good since tractors need to be heavy. And it was very handy for using inside a greenhouse since there were no emisisons. He had enough charge for a regular day's work and it would charge up ready to go the next day.

Some electric tractors have a solar roof that doubles as its own garage/sun protactin/rain protection. Just park it in the sun and it charges itself.

Tim Anderson made a neat self-charging vehicle. http://www.instructables.com/id/SolarWelder/

BONUS: Electric vehicles can double as a mobile DC welder!
loafers1 year ago
I love this. I've been hoping to put together something similar to this for a while now. My main concern with putting a body to the frame was always the weight for the motor and operator to push along, what've you worked out the assumed unladen weight of yours to be? How did you go finding struts that'd work for the suspension on something so small and light?

I'm curious to a few things: Do you plan to have more than one drive wheel? Is the driver going to be the only person faced with a set of pedals? Will the pedal operated part of it have gears like a mountain bike?

p.s. The Tonbrella joke gave me a good little chuckle, just thought I'd say so.
snotty (author)  loafers1 year ago
G'day, mate;

Excellent questions! I'll see if I can answer some.

Weight: The wooden monocoque body will probably be around 50 lbs. The wheels could add another 30 lbs or so depending on what I use. I have an old dirtbike back wheel and swing arm for extra strength but a hefty mountain bike swing arm and wheel might work fine at much less weight. The motor I'll start off with is about 10 lbs and the battery is about 9 lbs. So 50 + 30 + 10 + 9 = 99. Somehow I think it's going to get a little heavier though once I add cup holders etc. Later on I plan to upgrade to a Crystalyte 5403 motor at 27 lbs but for now I'm starting small.

How did I go finding struts that'd work for the suspension on something so small and light? Well, I haven't yet. If I can't source anything I'll have to steer away from the MacPherson strut design to something like a trailing arm system or a double wishbone. I'd like to keep it light and simple. I'm thinking I'll try out using half a mountain bike fork on each side as the main strut. This should match the weight requirements more or less. The only problem is I'm not sure about the rotational and off axis loading. Otherwise I might try a motorbike fork or a strut from a very small car/dunebuggy. I think the original wooden car I saw used a bit of closed cell foam sandwiched between two disks as the suspension. It kind of worked.

Drive wheel: I intend to drive with the single rear wheel just like a bike. For those trying this with an electric hub motor, beware of shearing off the freewheel threads on the aluminum side cover. I've seen it happen when there's too much power put through the chain. This is one reason I'm starting with a rear motorcycle wheel; it's strong and meant to take more power than this vehicle should ever see.

Pedals: I hope to have both people in front pedaling using two or three sets of crank arms ganged together in a "W" arrangement. like this guy: http://youtu.be/4LljkekeDD4?t=15m3s
But initially I will have one set of pedals. And yes, I intend to have fairly high and low gears.

Yes, I'm glad you like my tonbrella gag. Maybe this will seem like more of a joke if/when gasoline is expensive like in that classic Australian movie The Roadwarrior.

Anyways, I'm back at school now so please don't wait for me. Go grab a jigsaw and make your own! I'll race ya. Just make sure to share lots of pictures with us.
loafers snotty1 year ago
Haha, adding a tinge of Aussie to help relate? I like it! I'll respond in no particular order. With Petrol (Gasoline) at $1.60 per litre where I'm at, it's not far from that shocking figure. If I recall it was about $7 a gallon in the movie (about $1.80 per litre) we aren't far from that..

Weight wise, don't forget about the weight of brackets for the motor and battery, or the seat, there's always a lighter material. No less that's not a bad weight. I don't know much of monocoque structural designs and strut suspension. I own an old 4WD ute, with solid axles and separate chassis, if I'm not mistaken, some primitive forms of suspension that've been known to work well (for their era, being back at horse drawn carriages) were sometimes bowed timber (similar to a leaf spring) or even thick leather straps with the axle/beam held tight between the strips. Not sure how successful it may be, but with such little weight compared to even classic automobiles, some planned improvision may at least be fun to play with. My design, due to my knowledge was hence far heavier than yours. I'll see how I go with some new ideas, as you've given me plenty of them. Also, have you considered making a proper framed roof, an aluminium frame and canvas would likely not ruin the look too much I'm sure.
epierce1 year ago
A fantastic piece of woodwork! What is your motor set?
snotty (author)  epierce1 year ago
I will be using a Stokemonkey motor with a 25 amp controller. This will be waaay underpowered. A machine like this needs 30,000 watts not 1000 watts but I want to start with low power so I don't accidentally overload the car and nobody will drive it too hard at first.
changorey1 year ago
it would look cool steam-punked!
ray741 year ago
Incredible. Excited to see it complete.
This is great "MORE I NEED MORE!!!!"
l8nite1 year ago
this is such a TEASE ! looking forward to the conclusion