Commuter Booster - <1kg Friction Drive

[JennyB]

Friction drives are not to hard to overpower with your brakes in an emergency however, we have brake sensor inputs built in. Hard to make them univeral though. Just using a hall sensor input for this.

As these drives are typically hill assists rather then full time assist, the switch is only being used for a short period of time. I have used a simple button setup before and actually found it quite compfortable as you arn't chasing a postion to hold it in. Also looking at using a pressure sensitive strip rather then a button.

Lots of options to test. PAS is already to go also to meet our stupid Australian requirements in the near future.

2 Seconds may prove to be too long for de activation. This off cause will be optimized during testing.

Should have the code by the end of the week so looking forward to some more testing.

I don't know much about this, but it seems to me that a suitable pedal sensor could replace brake switches, even with a hub motor. After all, the very first thing you do in an emergency stop, even before you hit the brakes, is to stop pedalling. Try it.

It would also prevent the uninitiated applying full power when the bike is not moving. In fact, you could have a power selector switch that stayed on with having to be held in, so you need not have any extra controls on the bars at all.

 

[Kepler]

Looking really good Adrian. The remaining problems you have identified can be solved. And as with any set of problems, there are always anumber of ways to tackle them.

In relation to the advantages of a light weight drive on a lightweight bike, here is a great case in point.

My road bike is basically a Mountain Bike optimized for commuting. Runs ridged carbon forks, and 1.2" road tires on the standard 26" rim. Its a nice commuter, but nothing special. 13kg all up with drive and 2 x 5s 5ah LiPos.

Got invited to ride Beach road with a road cycling group of friends yesterday. Port Melbourne to Mordialloc and back. Group of 10 with all riders except me on full carbon high end road bikes. We rode at what they considered to be medium pace which held us at around 35kph to 40kph for most of the ride. At this pace we were doing quite a bit of passing with only the serious comp rides going past us. Man those big phaetons were scary. They were sitting on 45kph to 50kph wheel to wheel.

Anyway, I rode within my comfort zone using light assist on most inclines to keep pace with my younger better equipped buddies. At the end of the 60km ride, I had used only 3ahs of the 9 usable ah's I had onboard with the drive not even being warm under these riding conditions. I had a great ride and workout and never once slowed down the group. In fact I needed to demonstrate a bit of self-control not to go too quickly up the inclines.

Goes to show just how efficient a reasonable quality bike can be when coupled up with a light weight efficient drive system.

 

[adrian_sm]

Hmmm. Didn't think about PAS. This could be really nice. Even on my hub motor ebike, I am always pedaling when I am twisting the throttle.
Then I could have a modest amount of throttle by default, with a smooth ramp up set somehow. Then maybe an optional boost button at the bars, for when you want some extra kick.

Another reasons to try a little ebike sensorless controller, but with a PAS sensor input.

Thanks for that Jenny.

- Adrian

 

[umejopa]

Well the code is up and running. Have test it on RC controller and set the current limit to 3A to start and it will stop increse speed at that current soo it works.
May been some testing to get it cut the current nicer now it go up and dow by 0.3A but it may be better if the current is more normal ex 45A .
Have some testing with the regulator speed and how it slow down.
If you can make a connection and load the program you can test it
Have you working with ATtiny before ?
Some soldering is needed to be done to have a input for speed and output for RC controller and may a pot to set max current.
Think I will add that to mine soon. ( Now it fixed in the program)
//Jonas

 

[adrian_sm]

Looking really good Adrian. The remaining problems you have identified can be solved. And as with any set of problems, there are always anumber of ways to tackle them.

In relation to the advantages of a light weight drive on a lightweight bike, here is a great case in point.

My road bike is basically a Mountain Bike optimized for commuting. Runs ridged carbon forks, and 1.2" road tires on the standard 26" rim. Its a nice commuter, but nothing special. 13kg all up with drive and 2 x 5s 5ah LiPos.

Got invited to ride Beach road with a road cycling group of friends yesterday. Port Melbourne to Mordialloc and back. Group of 10 with all riders except me on full carbon high end road bikes. We rode at what they considered to be medium pace which held us at around 35kph to 40kph for most of the ride. At this pace we were doing quite a bit of passing with only the serious comp rides going past us. Man those big phaetons were scary. They were sitting on 45kph to 50kph wheel to wheel.

Anyway, I rode within my comfort zone using light assist on most inclines to keep pace with my younger better equipped buddies. At the end of the 60km ride, I had used only 3ahs of the 9 usable ah's I had onboard with the drive not even being warm under these riding conditions. I had a great ride and workout and never once slowed down the group. In fact I needed to demonstrate a bit of self-control not to go too quickly up the inclines.

Goes to show just how efficient a reasonable quality bike can be when coupled up with a light weight efficient drive system.

Your right there John. It is a pretty attractive offering isn't it.

Did you get many comments from the lycra crowd. If anyone is going to have a crack at the ebike, I would have thought it would be the weekend warriors on Beech Rd.

3ah @ 5s? That is pretty good for keeping up with the young'uns. Let's see that's about 60wh, over 90mins.
That is only averaging ~40w, and only about ~1wh/km assist. 8)

BTW. How is you new fandangle throttle controller uC thingy coming along.

- Adrian

 

[adrian_sm]

Well the code is up and running. Have test it on RC controller and set the current limit to 3A to start and it will stop increse speed at that current soo it works.
May been some testing to get it cut the current nicer now it go up and dow by 0.3A but it may be better if the current is more normal ex 45A .
Have some testing with the regulator speed and how it slow down.
If you can make a connection and load the program you can test it
Have you working with ATtiny before ?
Some soldering is needed to be done to have a input for speed and output for RC controller and may a pot to set max current.
Think I will add that to mine soon. ( Now it fixed in the program)
//Jonas

Sounds like you are making some great progress. I haven't done any work with ATtiny before, but full-throttle on the forum has, and he works in the same building as me. So I am sure I can get him to help out, in loading the program, or setting me up so I can.

I would be pretty keen to get this working, and don't mind making the required mods to the watt-meter.

- Adrian

 

[Kepler]

Your right there John. It is a pretty attractive offering isn't it.

Did you get many comments from the lycra crowd. If anyone is going to have a crack at the ebike, I would have thought it would be the weekend warriors on Beech Rd.

3ah @ 5s? That is pretty good for keeping up with the young'uns. Let's see that's about 60wh, over 90mins.
That is only averaging ~40w, and only about ~1wh/km assist. 8)

BTW. How is you new fandangle throttle controller uC thingy coming along.

- Adrian

Its amazing how little assist you really need if you are willing to work hard as well. I think the guys I were riding with were pleased I had the assist as I am sure they thought I was going to slow them down.

New button throttle is very close to finished. It works a treat and think it is the perfect type of throttle for an assist drive.

Has some great features:

Still has a minimum start speed to avoid sync issues.
When you engage the drive, the interface matches your throttle input to the given wheel speed so you are close to the correct throttle setting for what ever speed you are going when you engage.
Quick repeated presses ramp the throttle up in controlled steps.
Multiple pre set current limits are mapped against speed to guard against overloading the ESC especially when throttling up at low speeds.
Release the button for 0.4 second and the drive drops out.
Works with any spring loaded button.
Lots of other goodies built in too but I will save all those details for later

 

[adrian_sm]

That's a pretty impressive list of features already.

Your killing us here. Just release this thing. Or at least give me one to play with

In all seriousness, when do you think they will be ready for release. Because these sort of smarts is what will enable the friction drives to really have some user appeal. Ground breaking stuff. Well done in pushing its development along, it will be a real asset to the community.

- Adrian

 

[deVries]

New button throttle is very close to finished. It works a treat and think it is the perfect type of throttle for an assist drive.

Has some great features:

Still has a minimum start speed to avoid sync issues.
When you engage the drive, the interface matches your throttle input to the given wheel speed so you are close to the correct throttle setting for what ever speed you are going when you engage.
Quick repeated presses ramp the throttle up in controlled steps.
Multiple pre set current limits are mapped against speed to guard against overloading the ESC especially when throttling up at low speeds.
Release the button for 0.4 second and the drive drops out.
Works with any spring loaded button.
Lots of other goodies built in too but I will save all those details for later

I realize you have an ongoing commercial product to go with your new throttle, but can you make this new throttle available or "open source" it to the DIY crowd at ES too? It ought to be "adaptable" for other friction drive set-ups being done on ES. None of this would be in direct competition with your commercial product anyway.

Thanks for such an innovative throttle, but I hope it too can be "free standing" and not locked into your product exclusively, well, at least for ES members.

Thanks for keeping us up to date...

 

[Solcar]

I have now make a controll loop in the wattmeter that take down speed if current go to high only thing can not test it on E-bike before the snow is gone
How fast have you the controll loop Solcar ?
Do you contoll a RC controller or have a complettly own ?
I now check current and adjust the speed evry 20mS

The control loop is very slow. I added capacitance in parallel with the feedback to slow it down.

It is my own design and build. I use a brushed motor though. It's simple with the trade-off of bigger size and lower power and general efficiency.

 

[Kepler]

That's a pretty impressive list of features already.

Your killing us here. Just release this thing. Or at least give me one to play with

In all seriousness, when do you think they will be ready for release. Because these sort of smarts is what will enable the friction drives to really have some user appeal. Ground breaking stuff. Well done in pushing its development along, it will be a real asset to the community.

- Adrian

Every time I have said its a few weeks away, something changes and more development time is needed. That being said, the alpha units are quite stable now and we are currently building 6 units for limited release hopefully before Christmas. Also you are welcome to test ride my test bike anytime and have a feel how the button throttle reacts.

This interface is being specifically designed for my drive so that it can be sold as a comercial package ready to bolt on a go. That being said, I will be making it available to ES members also as a specific interface for all the DYI friction drives out there. Keep in mind, this interface is not designed for high powered RC setups. 6S LiPo and about 1500W is the maximum spec.

 

[deVries]

That being said, I will be making it available to ES members also as a specific interface for all the DYI friction drives out there. Keep in mind, this interface is not designed for high powered RC setups. 6S LiPo and about 1500W is the maximum spec.

Maybe, for ES members, you could allow for the design to be tweaked further for slightly more volts and watts?

Any idea when ES members can get a hold of the design or set-up?

Many thanks for all the work you've done with this. Has anyone on ES posted a build thread using your kit that they also bought from you?

I had to be away from ES through July, August, and September... someone in the hospital, etc., so I missed out on your prototype run and introduction to ES.

 

[Kepler]

That being said, I will be making it available to ES members also as a specific interface for all the DYI friction drives out there. Keep in mind, this interface is not designed for high powered RC setups. 6S LiPo and about 1500W is the maximum spec.

Maybe, for ES members, you could allow for the design to be tweaked further for slightly more volts and watts?

Any idea when ES members can get a hold of the design or set-up?

Many thanks for all the work you've done with this. Has anyone on ES posted a build thread using your kit that they also bought from you?

I had to be away from ES through July, August, and September... someone in the hospital, etc., so I missed out on your prototype run and introduction to ES.

Here is a review and testing thread on the drive http://www.endless-sphere.com/forums/viewtopic.php?f=4&t=22026

Sorry, no plans for a high powered version. The interface is really a means to an end so the drive can be sold as a complete unit. Happy to get it out to ES members in the near future though.

 

[adrian_sm]

I was driving along the other day and saw a set of fenders that would really suit a friction drive like hidden power or mine.
I had never seen the style before, but managed to find them with a bit of googling. They are the Planet Bike SpeedEZ, designed to be mounted on bikes with out fender lugs, but the great thing is that they don't extend down infront of the seat stays where this style of friction drive lives.

Amazon appear to stock them.
Planet Bike SpeedEX Bicycle Fenders

Here are the pics. Available in black or silver for the aesthetically inclined.

The front one looks pretty pointless, as it is the spray kick up off the top of the tyre that hits you in th face, but the back one looks like it would do the trick, and play nice with the friction drive.

 

[adrian_sm]

New button throttle is very close to finished. It works a treat and think it is the perfect type of throttle for an assist drive.

Has some great features:

Still has a minimum start speed to avoid sync issues.
When you engage the drive, the interface matches your throttle input to the given wheel speed so you are close to the correct throttle setting for what ever speed you are going when you engage.
Quick repeated presses ramp the throttle up in controlled steps.
Multiple pre set current limits are mapped against speed to guard against overloading the ESC especially when throttling up at low speeds.
Release the button for 0.4 second and the drive drops out.
Works with any spring loaded button.
Lots of other goodies built in too but I will save all those details for later

I just wanted to mention how good the two bolded features are in your list, John.

Matching the motor speed to the wheel speed is awesome. That will have a huge impact on useability.
Secondly, the current limiting feature will be key to controlling the power, and ensuring reliable life for ESC and motor.

Well done.

- Adrian

 

[Kepler]

Thanks Adrian,

I really believe the interface is the missing piece of the RC based friction drive puzzle

 

[adrian_sm]

Totally agree!

..... and when I find a bit of spare time on a weekend, I might just give you a bell and drop around for a go.

Keep up the good work.


Update:


On a seperate note, testing has slowed down due to work commitments, family staying with us, and a dodgy 5s5000mah pack from hobbycity.

I order two, one was fine, the other had a dud cell at <1.0V.
Shipping back to the warrenty centre was going to be $23, so I decided to charge it up and give it a chance instead.
Currently on the charger, and looking okay, slowly balancing the pack, no excess heat, puffing, fire etc.

Time will tell.

- Adrian

 

[adrian_sm]

I had some musing time on a plane last night and realized I am chasing too many things at once with this build. Trying to debug multiple things at once.

So I will be getting my hardtail mountain bike back on the road as my test mule. This will let me use a standard throttle which will make it much easier to get to know the drive.

Since the Avanti MTB has a larger seat tube I'll probably just build a second unit with the larger motor. This will let me work out a few differences in the deadstops, springs etc that a longer motor creates.

Looks like I may have to order a few more things from HobbyKing so I can have two units up and running.


Now if only I wasn't on holidays, I would start making bits.

- Adrian

 

[umejopa]

Well Adrian now you have same setup as I have
Have make the current controll running better now and add a pot to set the level wene it with powerup.
Even more more snow here now so hard to test for me..

If you have time you can rebuld your Wattmeter and make it to RC-tester with current limit .


Upload the hex code for the flash Watt1.hex and the EEdata Watt1.eep and assebler code if you want to change some.
The setting for current can ben set by the computer but for test it is better to have it adjusted on the road.
I think 1000W input may be a good limmit... (22V x 45A)

//Jonas

 

[adrian_sm]

Great work Jonas.

When I get back from my holiday I'll give it a go.

Thanks again for sharing.

- Adrian

 

[deVries]

Here is a review and testing thread on the drive http://www.endless-sphere.com/forums/viewtopic.php?f=4&t=22026

Sorry, no plans for a high powered version. The interface is really a means to an end so the drive can be sold as a complete unit. Happy to get it out to ES members in the near future though.

Ok, when are you going to start a new thread on your new "Avatar Design" ???

Obviously, you've been working on an idea that went through my head from the beginning of your first prototype design. Two speeds or a two geared drive...

Let's check it out... 8)

When will you post about it? Christmas is coming... :wink:

Thanks

 

[adrian_sm]

Back from holiday now, was an awesome trip to Cradle Mountain in Tassie. Here is a few pics from the trip.


View attachment 2

UPDATE: Throttle
After being frustrated with the dodgy excuse for a thottle that I knocked up before, I thought I better get something more conventional while I get this drive up and running. So Before I embark on making use of Jonas' work on modifying a Watt Meter to do the job, I decided to follow Hillhater's version of a modified servo tester with a hall throttle input. Thanks Hillhater.

Seems to work fine getting full throttle range. Only issue is the cheap thumb throttle I am using is a bit sticky, so it wasn't as smooth when I slowly adjust the speed.

Here is a few pics of what I did. And the bench test parts, which will be getting put together on my old Avanti hardtail mountain bike soon.




- Adrian

P.S. @Kepler.
John, you have to admit you are a bit of a tease. Updating your avatar with unreleased products. Dropping tasty little tid bits about your throttle interface, without let people know when they may be able to get their hands on it. Come on already.

 

[adrian_sm]

Since I am building a second unit, I thought I would get a second ESC to try out.

This time I went with the $60 TURNIGY K-Force 100A Brushless ESC, rather than the $36 Turnigy Brushless ESC 85A w/ 5A SBEC which has been fine so far.

Unfortunately the new 100A ESC doesn't have the ON/OFF switch that the cheaper ESC has.
But it does apparently have USB programmability, and firmware upgrade. But I don't see no USB port on it. From reading the comments on the HobbyKing site it looks like you need to buy some seperate progammer, that also allows you to connect it to the PC via USB. Great. How handy..... :x
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8996

 

[HAL9000v2.0]

Instead of programmer you can use USB linker for 8$.
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10628

 

[rearengine]

Hal!! What more can you tell us about the linker, Sounds really cool.. Are you using it , and how does it work ? Thanks for posting it ... Bill