Dogati Electric Superleggera

[j3tch1u]

LOL sorry I had to read the last page of this thread 3 times to find Taiwan..... Hmmm at least things are cheep there.

actually...new cars are about 2 1/2 times the price of north america and the avg home is $800 USD/sq ft (20 yr old apartment with no land).

we also pay more for bicycles and components (even if they are made here). my local bike shop asks me to shop online for them because prices + shipping are lower than their wholesale cost.

some things are cheaper (like machines, gas, food, electricity, water, tax) but the cost of living is definitely not as low as it was in the 60's.

[j3tch1u]

toango i am glad that my bike inspired you (as other peoples bikes have inspired me).

that high pitched whine is the harmonic impulse that our collective energies are sending out! either that or my tension is a tad high

Well i at first thought the forward seat position looked weird but the more i looked at it the more i like it. It adds to the exotism of the bike as surely this is a special build.

I just read this whole thread tonight for the first time and this build is so inspiring and i daresay that my fav bike on es would not be topped which is miles emoulton. i think you take top honors in my book on the thought and execution. Congratulations! I feel a little embarrassed to say this but you are my hero just from building a fantastic bike thanks for being an inspiration and sharing your 3 year project.

One thing though after seeing the video is the bike sounds really loud with a high pitched whine. Surely there can be a design that would lessen that noise.

Subject: Mag Max: compact 2-stage drive /w mag clutch brake regen

:lol: duly noted.

Hey Ben,

Can you do everyone a favor and leave the seat folded upward? It looks really odd folded down and does not give an accurate impression of what the bike really should look like.

It is like leaving the cover on a Ferrari at a show.

Matt

[j3tch1u]

notice to astro motor owners. i discovered my 3220 was shorted to the chassis making for a "lively" ride. culprit was: end termination shrink tape worn out by heat and/or wear. it would be a good idea to double-up on the shrink tape here. happened only after a few rides.

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[mdd0127]

My 3220 did exactly the same thing.....in fact it came shorted from the factory, probably costing me a few hundred bucks worth of controllers and many many hours of frustrating troubleshooting.

Screw Astro. Their service sucks and apparently QC is going downhill too. Someone honest and on top of their game needs to buy out the idiots that bought it from Bob.

I've put my whole project on hold until there is a decent motor manufacturer, good controllers, batteries available from someone with good business ethics, and for people to actually be in the financial position to buy a well built, high quality e-bike. Don't know if it will ever happen though. The frame design and everything else is all there......just waiting for the electric drive supply chain to catch up.


Your creation is amazing BTW!

[texaspyro]

It would be fun to bring deathbike there.

And a CrazyBike or two...

[ElliottE]

Regarding motor suppliers - I'm beginning to wonder if maybe the way to go is to load up on the cheap RC motors brands, pull them apart, sort them into bins and then assemble custom motors from the parts? I'm seeing some outrunner designs in the 1000 watt range for around $120 to $150 that look promising, but I seriously doubt you could just grab them out of a box and count on serious reliable performance out of them. But, if you were to take the time to disassemble them, carefully inspect and/or repair the components, then re-assemble with real attention to tolerances and quality maybe you'd have something?

As of now, who makes the best R/C style motors in the 1000 watt range for e-bikes? I'd love to hear some opinions on that from everyone.

[ilia-45]

Phenomenal job well done

[h0tr0d]

Awesome Buid!!!!

I'm reaaaaaaaly interested in the regen braking of your bike, is it working? with clutch and all?
Controller settings, give us anything!

Thanks!

notice to astro motor owners. i discovered my 3220 was shorted to the chassis making for a "lively" ride. culprit was: end termination shrink tape worn out by heat and/or wear. it would be a good idea to double-up on the shrink tape here. happened only after a few rides.

[Kin]

It's been great to read through this thread. Beautiful build.



Youtube says you closed your account, so I cant see the videos a few pages back. Was that intentional, or just a mistake?

[Kin]

It's been great to read through this thread. Beautiful build.



Youtube says you closed your account, so I cant see the videos a few pages back. Was that intentional, or just a mistake?

[Stevil_Knevil]

Nominated for ..the most awesome ebike.. EVER.

8^o.....

viewtopic.php?f=6&t=45498

[j3tch1u]

hey guys, sorry i was on a bit of hiatus. back now and started converting a montague paratrooper for touring the country. it will be a full-size folding electric that i can bring on the high speed rail and explore the land ie. FREEDOM! it will be everything dogati is not--low key, transportable and reliable

[j3tch1u]

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[Tommy L]

Awesome work here! I'm glad that you "Bump" this thread!

Could you tell me the purpose of detachable Drop Outs?
And when you changed your front fork to Triple Crown (tree) what did you use?

Thank you!


Tommy L sends....

[MattyCiii]

hey guys, sorry i was on a bit of hiatus. back now and started converting a montague paratrooper for touring the country. it will be a full-size folding electric that i can bring on the high speed rail and explore the land ie. FREEDOM! it will be everything dogati is not--low key, transportable and reliable

Nothing beats a folding bike for versatility. I've taken mine on AMTRAK intercity rail, folded just the handlebars & put it in the belly of an intercity bus, and have had it on subways, on front-mounted city bus racks, and in the boot of several cars. I can pedal mine easily 10+ miles (probably a lot more) at near "normal bicycle" speed, even with the drag of the extra chain/freewheel, the extra weight of the batteries and motor, and with several Kg and cm^3 of tools & cargo.

I can't wait to see what you do with a folding bike!!

[j3tch1u]

hi tommy, the front fork is a white brothers dh3. no specific reason for the detachable drop outs other than design.

Awesome work here! I'm glad that you "Bump" this thread!

Could you tell me the purpose of detachable Drop Outs?
And when you changed your front fork to Triple Crown (tree) what did you use?

Thank you!


Tommy L sends....

[j3tch1u]

right on matty, that's exactly what i had in mind--leverage the infrastructure and go beyond what planes, trains and autos can do

it also comes with a unique set of challenges: has to have enough range/power for the terrain yet be light enough to throw around and needs to be very reliable.

Nothing beats a folding bike for versatility. I've taken mine on AMTRAK intercity rail, folded just the handlebars & put it in the belly of an intercity bus, and have had it on subways, on front-mounted city bus racks, and in the boot of several cars. I can pedal mine easily 10+ miles (probably a lot more) at near "normal bicycle" speed, even with the drag of the extra chain/freewheel, the extra weight of the batteries and motor, and with several Kg and cm^3 of tools & cargo.

I can't wait to see what you do with a folding bike!!

[j3tch1u]

after riding a zero-s (thanks again luke for that memorable night ride) i decided dogati NEEDS to go sensored. so..i picked up one of these capacitive commutation encoders: http://www.cui.com/product/components/e ... r/amt303-v for a quick drop in solution. here are the steps i took to make it work (btw, these things are pretty tiny):

1. chucked the 3220 rotor onto my hobby lathe
2. drilled and tapped an M4 thread in the shaft (rear)
3. used a countersunk M4 screw to attach the encoder (the countersink helps secure the plastic encoder bushing firmly to the shaft axially and radially)
4. used some hot glue to temporarily secure the encoder housing.
5. connected the encoder to the programming board and set: direction (CCW), output (QAQB), resolution (1024), # poles (8) and left the commutation offset at 0.

this board has a nifty auto-zero function that gets stored into eeprom so you don't need to fiddle around with the alignment. however this only works if you know the correct commutation offset (for wye, offset is 0). i wasn't sure what the offset should be for my delta winded 3220 so i still had to adjust the encoder. running sensorless it draws 1.5A at WOT so i turned the encoder until it matched that. hooked it up to my kelly kbs controller and..the start-up is as smooth as margerine, niiiice

one thing to be aware of, you need to short GND_C with GND (pins 14 and 4) when hooking up to your motor to put it into normal operating mode (vs spi comm mode). it's written in really small print on the manual and easy to miss (this had me puzzled for a few hours).

so there you have it, a sensored 3220 for $35 bucks from digikey (http://www.digikey.com/product-detail/e ... 47?cur=USD) and about 40 mins to set it up.

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chucked back up onto the lathe to check commutation signals against BEMF on the scope. lookin good [thumbs up]

[fechter]

Cool encoder! How do you program it? Datasheet says contact CUI for details. I assume they supply the software and you use a PC.

If you apply power to a pair of phase wires (use current limited source), the rotor will align itself a zero position. This should be true for both delta and wye.

[j3tch1u]

if you buy the demo kit (http://www.digikey.com/product-detail/e ... 51?cur=USD) you just configure the settings using the programming board

Cool encoder! How do you program it? Datasheet says contact CUI for details. I assume they supply the software and you use a PC.

If you apply power to a pair of phase wires (use current limited source), the rotor will align itself a zero position. This should be true for both delta and wye.

[liveforphysics]

Awesome job!!

[j3tch1u]

hey bro, great to hear from you! will have to give you a dogati factory tour one of these days lol. of course i'd have to inject a special "substance" into your bloodstream so you don't remember what you saw.

Awesome job!!

[mwkeefer]

Looks like it uses a typical SPI interface to configure most everything including resolution and poles, there appears to be a manual method for setting offset to align for commutation. I'm going to try to contact them and see if they will release the software or the protocol, then an SPI Interface shortcut or other ATmega style MCU could handle the interface... buying a developers evaluation kit just to get the programming board seems a bit of a waste but it's a great idea for adding sensors to an Astro and easily reproducible.

-Mike

[j3tch1u]

so..i'm building a new triangle pack for my cross country ebike using Panasonic NCR18650PD cells. i really like Allcell's passive cooling approach so I thought i'd try to cook my own PCM. since i don't have access to graphite nano-matrix making equipment, I am just using 3mm micro-cell honeycomb aluminum core as the structural matrix and thermal conductor. for the PCM, i am using paraffin wax (i have some outdoor citronella candles from costco so i'll use those). when i'm touring around i'll know when the batteries heat up when i smell the citronella/lemongrass--it also has the nice side-benefit of keeping the skeeters at bay.

theoretically, the fine honeycomb will rapidly conduct heat away from the cell to the wax. when the wax changes phase from solid to liquid, it's thermal capacity increases (the liquified wax is sealed inside the honeycomb so it can't leak out). as the wax cools and solidifies, the excess heat is slowly transferred to an aluminum battery frame surrounding the honeycomb and radiated out into the environment.

for proof of concept, i'll be making a small block of 2p3s and run them through a series of charge/discharge tests while monitoring the temperatures at different locations/points in time. in the end i will do a overcharge destruction test of one cell to evaluate the PCM's effectiveness against thermal runaway.

on the left is carbon coated paper honeycomb and aluminum on the right. i ruled out the carbon coated because it miserably fails the "bic lighter test".

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ingredients in the candle wax (made in china)

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candle comes in a handy copper bucket ready for hot plate

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mmm..pcm hotpot ready to serve

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[fechter]

in the end i will do a overcharge destruction test of one cell to evaluate the PCM's effectiveness against thermal runaway.

Be sure to have video

Interesting idea. The outer housing will need to be sealed to prevent the wax from dripping out. Do you know what the melting temp of the wax is? It would be nice if there was a non-flammable PCM.