Commuter Booster - <1kg Friction Drive

[adrian_sm]

Test ride went well. New adjustment methods work really well. Was able to tweak the geometry and engagement quickly, and easily.
New thumb throttle makes a big difference in useability. It softened the engagement purely due to the time required to move the throttle. Also much easier to tweak the throttle to the amount of assist you want.

Managed to pull 80-100 amps according to the watt-meter. So 1600-2000 watts .
After burning off about 3Ah from the battery, playing around on local streets the motor was warm to touch, controller had no obvious heat.
I think long term I would want to be able to restrict the max current, to make sure I don't overheat the motor lugging up a hill, in the lower inefficient range of motor speeds. Top speed seemed low, but this may due to me being used to my 80v hub motor ebike, that I usually cruise at 50kph on.

On a negative note, this is not a stealth bike, it has the typically RC scream. Not enough to scare pedestrians, but enough to turn heads. Guess I am spoiled with my direct drive hub motor, which has no really sound at all when cruising along. Also going over bumps causes the motor to bounce and touch the tyre, not a big deal but thought it worth of mentioning.

Really need to go for a decent length ride, and give it a proper shake down.

Getting pretty excited, this is definetely maturing into a really useable system. Meeting all the objectives I had. Light weight, cheap, good performance, minimal parts, easy to make, simple to use.

I also jsut weighed the bikes.

The road bike with the first prototype weighed in at 11.8kg (26lbs), and my heavier hardtail MTB, with prototype 2, with the heavier motor, weighed in at 15.8kg, or 35lbs. It is such a different experience riding a light efficient bike again, but still being able to get that 1000+w push.

- Adrian

[adrian_sm]

. Also going over bumps causes the motor to bounce and touch the tyre, not a big deal but thought it worth of mentioning.

Thinking about this a bit more, Kepler's eboost geometry will suffer from this issue much less than my design, since the pivot point for the motor is nearly directly above the motor. Where as mine in cantilevered out.

[adrian_sm]

I quickly modelled up the current prototype 2 design with Google Sketchup, and found out that with a plugin in I could create a 3D pdf file.
The model is pretty rough but representative, even with the weird sized pivot and clamp blocks. So if you are interested here is a 3D model you can open up, spin around, hide parts, and generally get a better look at the design.

- Adrian

[deVries]

I quickly modelled up the current prototype 2 design with Google Sketchup, and found out that with a plugin in I could create a 3D pdf file.
The model is pretty rough but representative, even with the weird sized pivot and clamp blocks. So if you are interested here is a 3D model you can open up, spin around, hide parts, and generally get a better look at the design.

Pretty darn kool... Nice design on 3D. Look forward to your RW tests & performance...

[adrian_sm]

Pretty darn kool... Nice design on 3D. Look forward to your RW tests & performance...

Thanks. I just wish it would stop bloody raining here in Melbourne, so I can get some decent road time. I am heading interstate on Tuesday, and I won't be back for a couple of weeks. So if I don't get a ride in tomorrow, it won't be until next year.

This time of year is just crazy. Between work, kids, and the usual festive social engagements, I really struggle to get any time to play with this. It is so frustrating now that I have the whole thing up and running.

But from all the recent rides, it looks like it just works. I need to pretty it up and package it a bit better (hence the CAD models), but the mechanicals are all fully functional. There will be things to tweak as I get more road time. But the developement focus will now shift to sorting out the electronics side of things, such as throttles for a road bike, packaging the ESC and throttle interface better, maybe finally getting around to trying out Jonas's excellent work on making the watt-meter a throttle interface, or getting my hands on Kepler's if he ever releases it to reduce low speed amps, and mounting multiple batteries securely and elegently.

I really need to find a good solution to the road bike handle bar throttle problems, because the drive really suits this type of bike. I have some linear sliding pots on their way, that I am keen to try. But this throttle is likely to be just as complicated as the whole of the friction drive. At least it gives me something to sketch out and design while on holiday.

- Adrian

[deVries]

...maybe finally getting around to trying out Jonas's excellent work on making the watt-meter a throttle interface, or getting my hands on Kepler's if he ever releases it to reduce low speed amps...

Speaking of Kepler... ...we haven't heard a peep out of him lately about his new throttle push-button speed design.

Ok, Kepler, it's time for another ETA update... ...you've got waiting (now restless natives) beta-testers or ES customers ready to go... so, wwaaddaa you say, mate?

Hmmm, I guess Jonas has a thread somewhere on the watt-meter throttle idea and R&D... will have to check that out too...

Anyways, thanks for the update Adrian. I'm less than a month or two away from doing some kind of friction drive myself. Waiting to see if EVTodd is going to add another friction thread too...

[adrian_sm]

Speaking of Kepler... ...we haven't heard a peep out of him lately about his new throttle push-button speed design.

Bit of boy who cried wolf syndrome probably. Or more likely just lack of time like me, family, kids, full time+ job, silly session. Usual excuses.

Hmmm, I guess Jonas has a thread somewhere on the watt-meter throttle idea and R&D... will have to check that out too...

He nicely dropped some code in this thread, that he used to turn a standard watt-meter into a throttle interface, and current limitter.
Here is the post. Ican't remember where the rest of the history of that is, but a quick search should turn it up.

Good luck with your friction drive. What style are you planning on? What type of bike? Feel free to design, build, debug and send me a throttle suitable for drop bars....

- Adrian

[umejopa]

Good work Adrian
Even more snow here now soo no real testing for me.
Only made a LVC in software to save the batteri.

//Jonas

[Kepler]

Looks really good Adrian. The design has matured nicely.

Thanks for the digs fella's So much to do, so little time. Just so happens I will have the latest version of the interface this week. Really looking forward to testing this one as it is much closer to the production version.

For those interested in how different colour anodizing looks, her is one of my drives in blue.

[adrian_sm]

Looks really good Adrian. The design has matured nicely.

Thanks John, and Merry Xmas to you and your family. Hope you have a good break, and get a chance to unwind.

Thanks for the digs fella's So much to do, so little time. Just so happens I will have the latest version of the interface this week. Really looking forward to testing this one as it is much closer to the production version.

Sure you do. If I hadn't seen one of these little devices in the flesh I would start to think you are having us all on.
Hope this one is the final, without too much more to tweak as the suspense is killing us.

For those interested in how different colour anodizing looks, her is one of my drives in blue.

Is that the Henry Ford "Blue", or is my screen deceiving me?

[adrian_sm]

Another burn around a few blocks. I rode it with assist pretty much all the time, except on down hill runs, not trying to conserve batteries at all. Using WOT whenever possible.

Distance: ~6kms
Battery used: 4.5Ah 82 Wh (from a single 5s5000mah 20c pack)
Power Peak: 1800 watts
Amp peak: 103 Amps
Volt Min: 17.26 Volts
Efficiency: 13-14 wh/km.

I didn't have the Cycle Analyst on the bike, so I am not sure of the average speed etc. But I did have the GPS on. Looks like I was doing about 37-38kph on the flats, 30-35kph up the hills depending on how nasty they were.

Motor was warm to the touch at the end, and once I found my IR thermometer (~2 minutes after stopping) motor coils were at 45 deg-C. ESC was cool.

Here is a link to the GPS data, with slightly trimmed start finish.
http://www.everytrail.com/view_trip.php?trip_id=912183

2010-12-20 - CB2 - Test Ride - Map.PNG (57.46 KiB) Viewed 5210 times

2010-12-20 - CB2 - Test Ride - Stats.PNG (32.19 KiB) Viewed 5210 times

Other interesting data:
- no load WOT power for motor only: ~100w
- no load WOT power for motor fully engaged with wheel: ~180W
This is without a lot of optimisation of the amount of engagement the motor has with the tyre, but I was getting no slippage, even when pulling 1800 watts.

I also tried accelerating from a stand still after a small push off, and no sync issues, or exploding ESCs.

So far so good.

Oh and I found a roadbike from the google sketchup 3D warhouse so threw it in to the model, along with the ESC, and a couple of 5s5Ah batteries. Here is a screen grab.

CBv2 - Sketchup Model.PNG (28.06 KiB) Viewed 5210 times

- Adrian

[Kepler]

They are good numbers for the speed you are doing. I typically say 10km range with the 5ah pack. This is averaging 25 kph and keeping Watts under 1000. Once you start riding it like a bike as apposed to an ebike, you will find 4ah is good for more like 40km. The more I look at this design, the more I like it. We need to get one of my interfaces on this setup very soon.

[adrian_sm]

They are good numbers for the speed you are doing. I typically say 10km range with the 5ah pack. This is averaging 25 kph and keeping Watts under 1000. Once you start riding it like a bike as apposed to an ebike, you will find 4ah is good for more like 40km. The more I look at this design, the more I like it. We need to get one of my interfaces on this setup very soon.

Thanks John. It still needs a little bit of mechanical refinement, and I have an idea on how to integrate the ESC using the main pivot block as the heat sink. This would make it a much neater package. But may further restrict the number of frames it suits. This is going to be the biggest issue with this design over yours, as modern fancy frames have really closed down the space available in this area. Might be a better option to mount the electronics infront of the seat-tube, in a water-proof enclosure, and use it as one of the mounting points for batteries.

As for the interface. Bring it on. I'll be back in melbourne on the 6th of Jan. Any chance of hooking us up around then?

- Adrian

[Kepler]

It also has advantages over my design too and I am seeing opportunities for both designs. 6th of Jan onwards will be good. I am on annual leave then so we will have some time sort something out.

[Hillhater]

Kepler,
your new avatar looks interesting ? what have you included this time ? ...battery pack ?

[LI-ghtcycle]

Very exciting!! I am really pleased to see this build, seems that the Eboost and Commuter Booster are reviving the friction drive cult, and gaining new members daily! I know I am one now!

I am curious, Adrian, how much of the total weight of your road bike is the bike it's self, how much is the CB? Also, when you talk about hills, how steep are they, and I missed what voltage you are running the MTB, 5S or 6S? And again, I'm very interested to know how much of the weight of the MTB is CB and how much is the bike it's self, thanks!

Kepler - how's the interface coming along? I am SOOOO ready to ditch my thumb and grip throttles in favor of something that requires much less space and force to use. Anyhow, nice work the two of ya!

You may have inspired another off-shoot of your designs that I have just thought of .. .. I'll have to sketch it out tomorrow while charging LiPo before I share it, not sure if it's going to be as simple and solid.

If I don't hear from you all before the new year, Merry Christmas and Happy New Year! I understand that you both have lives, I just wish I had more equipment and knowledge so I could make more use of my time building something half as brilliant!

Keep up the good work, and don't forget to take enough brakes and ENJOY riding too!

[Kepler]

Kepler,
your new avatar looks interesting ? what have you included this time ? ...battery pack ?

Hi Hillhater,

You are correct, the battery is part of the drive package. The interface processor and motherboard are now on the handlebars so cables to throttle button, LCD, brake switch etc, are nice and short. This unit will also have an 18V output for some serious lighting options. The ESC is now in the lower compartment together with the interface daughterboard. The ESC plugs into the daughterboard which also picks up curent and voltage inputs. A secondary 5V power supply for a tail light is also provided.

The actual motor folds back on its pivot point by removing a pin so the unit is easier to fit in a backpack.

So the actual size and weight of the drive grows a bit but having the unit arranged as a compete package has some serious advantages over multiple pieces fitted all over the bike. Also having the the LiPo battery protected by aluminium side frames rather then a soft bag is an important commercial consideration.

Lots happening on the Kepler eboost front

[Kepler]

Very exciting!! I am really pleased to see this build, seems that the Eboost and Commuter Booster are reviving the friction drive cult, and gaining new members daily! I know I am one now!

I am curious, Adrian, how much of the total weight of your road bike is the bike it's self, how much is the CB? Also, when you talk about hills, how steep are they, and I missed what voltage you are running the MTB, 5S or 6S? And again, I'm very interested to know how much of the weight of the MTB is CB and how much is the bike it's self, thanks!

Kepler - how's the interface coming along? I am SOOOO ready to ditch my thumb and grip throttles in favor of something that requires much less space and force to use. Anyhow, nice work the two of ya!

You may have inspired another off-shoot of your designs that I have just thought of .. .. I'll have to sketch it out tomorrow while charging LiPo before I share it, not sure if it's going to be as simple and solid.

If I don't hear from you all before the new year, Merry Christmas and Happy New Year! I understand that you both have lives, I just wish I had more equipment and knowledge so I could make more use of my time building something half as brilliant!

Keep up the good work, and don't forget to take enough brakes and ENJOY riding too!

As you can see, the interface is going well. Dont worry Dayn, I will get the interface to you as soon as it is ready. Merry Christmas and Happy New Year to you too.

[adrian_sm]

I am curious, Adrian, how much of the total weight of your road bike is the bike it's self, how much is the CB?

Here are the weights.
v1 - with the smaller motor
http://endless-sphere.com/forums/viewto ... 60#p328977

0.74 kg drive only
0.9 kg for the whole system excluding battery

v2 - with larger motor, and single swing arm
http://endless-sphere.com/forums/viewto ... 80#p342336

1.2 kg drive only
1.4 kg for the whole system excluding battery

Then add however many batteries you want
6s5000mah = 0.793 kg
5s5000mah = 0.666 kg

So with a couple of batteries 5s5000mah batteries, and the new larger motor you still only add total of 2.7kg (6lbs) to your bike.

Also, when you talk about hills, how steep are they, and I missed what voltage you are running the MTB, 5S or 6S?

No idea on the grade of the slopes, you can interogate the GPS data I linked to above if you are really interested.
I was running the bike on 5S.

You may have inspired another off-shoot of your designs that I have just thought of .. .. I'll have to sketch it out tomorrow while charging LiPo before I share it, not sure if it's going to be as simple and solid.

Awesome. Can't wait to see it.

I just wish I had more equipment and knowledge so I could make more use of my time building something half as brilliant!

Hey my list of tools is pretty short for this design. I intentionally made it such that people could make their own with simple tools if they wanted to. But I know there will probably be bunch of people who just don't have the time or patience so I might end up making a small batch if people are interested.

Anyway if you want to do it yourself the main tools you would need are:
Angle grinder or hack saw - for cutting out swing arm, and sizing pivot/clamp blocks
Drill, various bits, and a hole saw to suit your seat tube size.
Taps - M4,M5,M6

I think that was pretty much it, apart from patience, but I manage to build mine without it.

- Adrian

[deVries]

Here is a link to the GPS data, with slightly trimmed start finish.
http://www.everytrail.com/view_trip.php?trip_id=912183

This is very interesting data. Can anyone recommend some GPS's that will be "ideal" for eBike use? I don't know "jack" about these devices... but, it's obvious for testing & comparison purposes this kind of data is very useful. Thanks for posting this data Adrian , and you were moving along at a really nice "high-end" bicycle speed for cruising fast even going up in elevation. I would be very satisfied traveling at those speeds. What would really be kool is to combine a video with that data, so one can actually see the data in RL action too. I did a quick ES search and found this is being done... check it out... Video Route Elevation Speed = Far! Out! Man (Original ES post about it: ES Post About GPS w/Video, etc.)

So the actual size and weight of the drive grows a bit but having the unit arranged as a compete package has some serious advantages over multiple pieces fitted all over the bike. Also having the the LiPo battery protected by aluminium side frames rather then a soft bag is an important commercial consideration.

What is the approximate total weight now without the battery? It would be nice to have a "plug-in" to add more batteries in parallel too.

Kepler suggestions: please start a thread soon about this new drive system. Why don't you offer some prototypes of these for ES members too? Also, start a thread on your new throttle set-up too. At least that will start putting these posts in your thread, since there is a high interest to follow your product & lend ideas or suggestions for it too. It's almost 2011, so you might as well get a head-start providing information on ES about it.

I guess we could start an inquiry & speculation thread about Kepler's new drive & throttle set-up... Hmmm, ...Ok, you have two weeks to start the thread, otherwise on January 3rd the inquiry & speculation thread will begin...

This gives you some R&R time for the holidays & maybe some R&D too...

[adrian_sm]

Wow ultimatums. Thats a bit rough.

I understand keeping things a bit more under wraps when it is a commercial developement. I would prefer John spends his time getting it right and on sale, rather than keeping us updated.

Keep up the good work.

[Kepler]

So the actual size and weight of the drive grows a bit but having the unit arranged as a compete package has some serious advantages over multiple pieces fitted all over the bike. Also having the the LiPo battery protected by aluminium side frames rather then a soft bag is an important commercial consideration.

What is the approximate total weight now without the battery? It would be nice to have a "plug-in" to add more batteries in parallel too.

Kepler suggestions: please start a thread soon about this new drive system. Why don't you offer some prototypes of these for ES members too? Also, start a thread on your new throttle set-up too. At least that will start putting these posts in your thread, since there is a high interest to follow your product & lend ideas or suggestions for it too. It's almost 2011, so you might as well get a head-start providing information on ES about it.

I guess we could start an inquiry & speculation thread about Kepler's new drive & throttle set-up... Hmmm, ...Ok, you have two weeks to start the thread, otherwise on January 3rd the inquiry & speculation thread will begin...

This gives you some R&R time for the holidays & maybe some R&D too...

Now I am scared
Sorry about the teasers but it just takes a lot of time to get it to a point where its ready to present. As Adrian pointed out, it is more a comercial venture now rather then a one off bike project. That being said, I will start up some dedicated threads as soon as the product is a presentable stage. I am mindful of hijacking Adrians fine thread even though he has been extremely gracious so far.

And just to answer your questions: Yes, it takes a second battery that can be attached with a velcro strap on top of the main battery although the main idea is to carry a second pack in backpack for quick swap over.

Weight is 1950 grams without battery. Considering a battery bag weighs around 200 grams and is no longer needed, net weight has actually decreased over the original design.

[LI-ghtcycle]

Whoa! The natives are getting restless!

I understand waiting until you have something solid to show before letting it go "live". I think if he jumped the gun then the buzz would be "why didn't he finish it before giving us beta test gear!?".

I too have held off some until I have got something solidly tested and sorted before taking it to potential customers, at the moment, I am just doing this as a hobby, but soon I hope to make this my living, and I really think that the Eboost and CB (Commuter Booster) are the best yet ideas in the friction drive world, especially as a commercial product, not saying everything else before wasn't good, just saying from what I have seen, these simple lightweight designs are filling a need that nothing I have seen in any form of E-Bike kit available.

I'm neither RC or friction drive literate yet, I know a little bit about 2 hub motor kits that I have used extensively, but these are still new to me, that's why I love coming here and seeing what great minds are building for us!

Keep up the good work, and thanks to BOTH Adrian and John for making these available for the rest of us to buy and/or build on our own!

[deVries]

Whoa! The natives are getting restless!

I understand waiting until you have something solid to show before letting it go "live". I think if he jumped the gun then the buzz would be "why didn't he finish it before giving us beta test gear!?".

If you follow Kepler's prototype build thread, then you can appreciate all the ideas ES members provided to Kepler to improve his V1 design. Everything on ES is pretty much DIY or "beta testing" someone's kit or modding someone's "design post" or build thread. No need for a stealth friction drive not to be posted on ES.

Nothing is "retail" at ES. It doesn't matter what happens here for our "internal use", except improvements , as far as affecting anyone's final retail product. It's obvious these friction design's have been reinvented & refined for years, since the 90's really. Note the flashy Korean design, recently found and posted on ES, was first made public by its patent application back in 2008. That's Pre-EVTodd, and EVTodd is the "Friction Man" on ES that got these recent f-designs all started... EVTodd is "the original" friction pioneer on ES.

Kepler knows I'm just giving him the razz... ...all this friction stuff is great fun to follow & watch with interest. Adrian, Hillhater, Spinningmagnets, EVTodd continue to add to the friction design mix. I'll be copying/modding or doing some-dang friction thing in 2011 too, so I hope to add someone's kit or mod a design for my friction eBike in a few months too.

I'm sure Kepler will be starting his threads soon or "the natives" will be restless again...

Anyway, if "I" try to start a thread for Kepler's new throttle or V2 design it will still be up to Kepler to decide when to post or reply. No pressure, ehhh, matey? (I expect Kepler will beat me to it.)

[adrian_sm]

When designing the Commuter Booster, I was trying to make something quite different froms John's eBoost. He did an awesome job but was following a slightly different design philosophy, and had different ideas on what was more important. So I made my own, to my own needs, but wasn't sure if anyone else would agree.

I started thinking about this again recently and thought I would summarise what I saw as the main differences between the mechanical design of each drive. Here is what I came up with.

eBoost vs Commuter Booster.PNG (47.27 KiB) Viewed 5148 times

I would be really interested to hear what others think. So correct anything I got wrong in my assessment. Tell me what you would prefer, what you think is still missing, or anything else you think of.

- Adrian