Brushless dual 6kw ALIEN Power system - electric longboard

[jacobbloy]

With this friction setup with a 70mm wheel and a 42mm it has a 1:1.7 ratio that gives us a speed with 4s 22mph
I'm thinking next I'm going to revers my shaft on my motor and then have the motor sitting above the wheel by a couple of cm and then still use the belt drive system.

 

[jacobbloy]

It's a bit of a crapy mock up but some thing like this.





Hope you guys like my Saturday fun!

 

[rf]

Please forgive me for saying this ... but abusing a motor in that way is terrible.

If no one had yet divised a belt or chain drive, or if you lived on a desert island with limited parts, it might be excusable.

Otherwise, it's just nasty. Abuse of hardware.

My apologies. Just had to get that off my chest.

Now if you want to build direct-drive hub motors inside the wheels, that would be very cool.

 

[jacobbloy]

Please forgive me for saying this ... but abusing a motor in that way is terrible.

If no one had yet divised a belt or chain drive, or if you lived on a desert island with limited parts, it might be excusable.

Otherwise, it's just nasty. Abuse of hardware.

My apologies. Just had to get that off my chest.

Now if you want to build direct-drive hub motors inside the wheels, that would be very cool.

Trust me when I say that it's not my preferred way of doing it at all I just sore the kick starter and only made it to see if it would work or if it would be good for the motors. Iv seen it done with bigger motors in ebikes but there not little 40mm motors. I would also say that kickr is using a higher kv also, this isn't good as through testing Bruno has found that a 1:3 is the better ratio to stop the motors being under to much strain this is why I changed it to still work with the puleys. Can u imagine wheel slips going up a hill making flat spots on your wheels

 

[simonjook]

Sure it works .... it's a really really old idea ... I know cos I copied one in the 90s . Unfortunately, without a self tensioning system it wont work for long as it eats up the wheels and they get smaller.... and eat up the wheels it will as they get quite hot and really start to fall apart fast (though wheels are better quality these days). I suspect it will also be quite unkind on motor bearings. It's advantage lies in being able to build in a release mechanism so you can uncouple them and get a proper freewheel.

It's nowhere near as good as a belt pulley setup but damn nice work whipping up a similar system so fast.

 

[simonjook]

Since someone already asked ... no, we did not have brushless motor in the 90s ... It was a motorcycle starter motor (I think) and a bunch of motorcycle batteries and yes it weighed an absolute ton.

 

[beetbocks]

a bit of an update- i have acquired a test ESC from Bruno which will allow me to use a dual 50mm and a dual 42mm set up on then rear- ( yes it looks possible with a couple of 4mm spacers on the wheels) so i'm in the process of fabricating a test esc cover with swappable batteries so i can swap between the 6s flat battery we've made and the 7s for the dual 50mm- its all looking quite and light. I'm using a XT 90 for the kill switch /plug and a xt60 for the charging . I will hopefully get the molds knocked up this week and then do the covers!! i'm quite exited i just hope the weather holds out for testing!!! the first test will be the 76mm wheels and the 40T gearing - then i can make it available..then on to the 90mm wheels and dual 50 motor 7s setup...

 

[beetbocks]

covers are nearly done - and there looking pretty nice..just a bit of trimming and a cooling slot to put in..and I'm trying to think of a way of fixing to the board..
notice how they slide nicely together ,I intend to make another cover to put the 7s battery in and this will fit in the ESC cover in the same way.. As there quite small they are also really strong -especially with all the curves on them..

 

[hillzofvalp]

Sure it works .... it's a really really old idea ... I know cos I copied one in the 90s . Unfortunately, without a self tensioning system it wont work for long as it eats up the wheels and they get smaller.... and eat up the wheels it will as they get quite hot and really start to fall apart fast (though wheels are better quality these days). I suspect it will also be quite unkind on motor bearings. It's advantage lies in being able to build in a release mechanism so you can uncouple them and get a proper freewheel.

It's nowhere near as good as a belt pulley setup but damn nice work whipping up a similar system so fast.

We are actually using a self-tensioning system as well as a polyurethane component which distributes grip evenly across outrunner surface and which takes the brunt of the wear (little to no wheel wear). It is cheap to replace if it wears down (think replacement truck bushings). We also have specced out motors which tolerate the added load acting upon the outrunner. Lastly, we have implemented a traction control system which virtually eliminates wear from excess slippage. Excess heat is caused by excess slippage. Polyurethane is difficult to get up to a constant 150 Celsius unless you are abusing wheels doing "thaning." No melting urethane involved. Just less kicking.

It's great to see so many different attempts at electric boards. I like what you guys are doing. If you haven't already, check out our new one-minute video in Chicago http://bit.ly/WindyCityKickr. Maybe some of you would like to join us for a ride sometime if you are in the area.

 

[jacobbloy]

Sure it works .... it's a really really old idea ... I know cos I copied one in the 90s . Unfortunately, without a self tensioning system it wont work for long as it eats up the wheels and they get smaller.... and eat up the wheels it will as they get quite hot and really start to fall apart fast (though wheels are better quality these days). I suspect it will also be quite unkind on motor bearings. It's advantage lies in being able to build in a release mechanism so you can uncouple them and get a proper freewheel.

It's nowhere near as good as a belt pulley setup but damn nice work whipping up a similar system so fast.

We are actually using a self-tensioning system as well as a polyurethane component which distributes grip evenly across outrunner surface and which takes the brunt of the wear (little to no wheel wear). It is cheap to replace if it wears down (think replacement truck bushings). We also have specced out motors which tolerate the added load acting upon the outrunner. Lastly, we have implemented a traction control system which virtually eliminates wear from excess slippage. Excess heat is caused by excess slippage. Polyurethane is difficult to get up to a constant 150 Celsius unless you are abusing wheels doing "thaning." No melting urethane involved. Just less kicking.

It's great to see so many different attempts at electric boards. I like what you guys are doing. If you haven't already, check out our new one-minute video in Chicago http://bit.ly/WindyCityKickr. Maybe some of you would like to join us for a ride sometime if you are in the area.

Don't think I can make it as I live in aus, but great to have you the innovation, I love that so many different options are surfacing, it gives us all a fresh new perspective and new grate ideas are born.
I have soon some one can can come up with an option to convert an outrunner into the core of a longboard wheel the in turn making it a hub motor but at this point I think the wear on the motor would be to great.

Great video

 

[hillzofvalp]

That's a very difficult challenge requiring ground-up design. Lots of issues with that design but it would definitely be cool and we've considered it.

Thanks for checking out the video! (maybe I should embed it) Actually, we're told that Australia is one of the biggest markets for eboarding. Do you have any evidence to support that or marketing venues you might suggest?

 

[jacobbloy]

That's a very difficult challenge requiring ground-up design. Lots of issues with that design but it would definitely be cool and we've considered it.

Thanks for checking out the video! (maybe I should embed it) Actually, we're told that Australia is one of the biggest markets for eboarding. Do you have any evidence to support that or marketing venues you might suggest?

Yes Australia is massive with longboarding and every one Iv talked to is very keen on the products that are around but want an easy turn key or bolt on system, like you guys and boosted have developed or like Richard and Bruno are working on.

One suggestion for you guys and I'm no expert but Velcro traps don't seem compelling to me, having some thing on my deck that could get in the way of my ever changing foot stance the strap is ok my Velcro wears out comes undone, I would suggest a clamp system to the rales of the deck or a tight silicone band not sure exactly I guess I haven't had a chance to test it

 

[hillzofvalp]

We are going to make it easy to use and as least cumbersome as possible. The cross-platform design constraint is a very big one. The suggestions you mentioned are on our list of considerations.

 

[beetbocks]

I think the kickr is a great concept and well thought out design , i agree with Jacob , the fixing straps need to be a bit less intrusive and look cooler. One question is - I assume there is no braking capacity ?
I do actually have an idea of a similar clip on device but with totally different design ethos. .. I've just not had the time to develop it .. Keep up the good work ..

 

[simonjook]

We are actually using a self-tensioning system as well as a polyurethane component which distributes grip evenly across outrunner surface and which takes the brunt of the wear (little to no wheel wear). It is cheap to replace if it wears down (think replacement truck bushings). We also have specced out motors which tolerate the added load acting upon the outrunner. Lastly, we have implemented a traction control system which virtually eliminates wear from excess slippage. Excess heat is caused by excess slippage. Polyurethane is difficult to get up to a constant 150 Celsius unless you are abusing wheels doing "thaning." No melting urethane involved. Just less kicking.

Great heat is caused by slipping by heat is also generated by the motor itself and through the deformation of the thane at the contact point. I'm not saying you didn't do it better nor that the PU isn't better but to pretend it wont get a lot of heat and friction through contact is a bit misleading. I'm am sure you're product is good and you've researched it but I'd rather eat up $10 belts quickly than $60 wheels.

On a different point, what happens if you put a little flatspot on your wheel in a poorly executed slide? Will it cope with that, require you to rotate out the wheel or will it actually helps smooth off the edges a bit?

Thanks for checking out the video! (maybe I should embed it) Actually, we're told that Australia is one of the biggest markets for eboarding. Do you have any evidence to support that or marketing venues you might suggest?

Practically all of Australia is connected to the surf/skate culture in perhaps a similar way that many see California or Hawaii. The problem is all almost all the population lives in 5 cities spaced at 1000km intervals so you really need to demo around each. You could target the big surf chains which would get you the most exposure.

I assume there is no braking capacity ?

Why wouldn't motor breaking work the same as belt drive?

 

[simonjook]

Yes Australia is massive with longboarding and every one Iv talked to is very keen on the products that are around but want an easy turn key or bolt on system, like you guys and boosted have developed or like Richard and Bruno are working on.

One suggestion for you guys and I'm no expert but Velcro traps don't seem compelling to me, having some thing on my deck that could get in the way of my ever changing foot stance the strap is ok my Velcro wears out comes undone, I would suggest a clamp system to the rales of the deck or a tight silicone band not sure exactly I guess I haven't had a chance to test it

I switchfoot all the time and my velcro has never been a problem in that regard as you need it tight so its been impossible for me to catch a foot but as you say it wears out especially when it gets walked on a lot. Even quality industrial grades the hooks gets flattened and under-perform. That said, it is replaceable and it is nice for those that dont want extra holes in their precious boards. In my case it's temporary until I get time to model up my final case (December).

 

[rf]

4. To slow down, use conventional boarding braking and bailing techniques as needed.

Ugh.

 

[hillzofvalp]

Again, if you minimize heat from slippage (by nearly eliminating the opportunity), spec the motor properly, etc. then thermal overload modes for any component of the system does not become an issue. We intend on publishing specifications on performance expectations mainly pertaining to rider weight and grade.

The motor sleeve will need to be replaced in a similar way to belts. We are aiming to make it closer to 78a so that, if anything, the sleeve will wear more than the wheel. It will likely compare in price to truck bushings. Bear in mind it is very common for un-driven longboard wheels to need to be rotated since they naturally wear unevenly from imbalances in weight distribution and inconsistencies due to riding style. Interestingly enough, my business partner (160lbs) used a prototype for over 500 miles with grip tape and experienced minimal wheel wear (probably 82a-84a). This prototype has excess slippage which will be corrected with software. It also has a limited contact patch and uneven load, which is corrected with our new model. We are excited to share the results within a couple months.

The flat spot question is a good one, but probably depends on the severity. Kickr will compensate in tension to a certain amount, possibly self-truing over time (fyi minimal wear to wheel in general). If the flat spot is enough to make the ride quality/comfort poor, it's probably enough to make Kickr's performance poorer (probably audible annoyance more than anything affecting drive mechanical performance) to the point that there are two reasons to swap the wheel. Kickr won't cause flat spots.

There currently is no braking capacity but we are looking into it. That is not an electronics issue (although it does add complexity we don't want to focus on atm)-- it is more of a mechanical issue. Kickr is self-tightening. Regen torque has the potential to loosen the motor from the truck if Kickr is not installed tightly enough. Again, we need to do more testing on this, it may actually work better than we originally thought with our pre-production model.

To all haters of human brakes vs. regenerative brakes-- We hear you. I'm less of skater than my partner, and I've jumped on a street board (with risers and longboard wheels) and rode around in campus traffic without a brake with no problem (200lbs). The human brain and good judgment is ultimately the best accident avoidance system. If I was going faster than 20mph I would probably require a brake on my electric skateboard. The nice thing about the Stealth mode is that you have better control in setting personal limits that you can maintain and feel comfortable with. This goes along well with the idea that the faster you can kick, the more likely you are to be more in-tune to your board and riding environment. You know what I mean?

 

[jacobbloy]

I thing electric braking is great and makes you fell more in control of your board but until the new firmware come out for Bruno's esc's living on hills most of the time I'm made to use foot braking any way and I'm confident in my ability to so it's not a problem. I understand at speeds of 30km up your board can get speed wobbles in those spit seconds your taking your foot off your deck and planting it on the ground if you don't have the experience but
I think all riders should learn to foot brake and learn to bail correctly as a fail same any way, after all I just had to have knee surgery after coming off my board.

 

[simonjook]

The motor sleeve will need to be replaced in a similar way to belts. We are aiming to make it closer to 78a so that, if anything, the sleeve will wear more than the wheel. It will likely compare in price to truck bushings. Bear in mind it is very common for un-driven longboard wheels to need to be rotated since they naturally wear unevenly from imbalances in weight distribution and inconsistencies due to riding style. Interestingly enough, my business partner (160lbs) used a prototype for over 500 miles with grip tape and experienced minimal wheel wear (probably 82a-84a). This prototype has excess slippage which will be corrected with software. It also has a limited contact patch and uneven load, which is corrected with our new model. We are excited to share the results within a couple months.

Would be good for your customers if the sleeve was something typically available that is repurposed. Obviously we wear out belts but should Alien give up on the business any number of suppliers of belts can provide replacements. It would be nice if your final product was similarly generic in wearing parts.

Braking is a big thing for many of us. I actually use the braking on my board more than the motor some days. I live in a very hilly area which is just not safe to free descend or slide so I never used to ride out from home much but actually walk 1km before I started riding. Now I ride every bit of my journey, to uni, to work and even to client meetings. Without brakes I wouldn't bother with the electric board and I wouldn't skate anywhere near as often. Now I don't represent everyone's need but I do represent I significant part of the market in braking being one of the main reasons for strapping on a motor.

Braking also adds significantly to the safety of riding a board especially at speed not just for me but for others. If I have to bail I do so with the brake engaged knowing the board will pull up in a couple of metres without my weight rather than ploughing into someone. Due to the double weight of an electric board that 3rd party safety factor is also import.

Now maybe you can't do braking because of the nature of your mounting system but if you can do braking that will put you on near level terms with belt based designs and significantly enhance the standing of your product.

 

[beetbocks]

I tend to agree with you simon .. I do really use the brake a lot ..
Maybe hillzoval could start a new thread to get everyone's opinion on the subject ..?

 

[whilechukwuzout]

I agree on the brakes as well. Perhaps a "gas" pad in the front and a "brake" pad in the rear might not be a bad idea. One concern I could see being valid is the slippage in a friction based system, and the consequences of using the motor for braking. In most friction based systems, the braking is a separate system (bikes, scooters).

 

[beetbocks]

Well after months and months of testing and testing i think i can finally say what my opinion is of all the various types of motors and drive systems..I will just give my experience of each power first then go on to say what I think of the rear dual vs diagonal drive.
We have come such a long way in the development of the drive systems and the ESC and motors and spent countless hours and money tweaking and improving along the way..Bruno has now got the ESC working beautifully with awesome acceleration and smooth braking and that's without sensors wait until those are available..... and i think the new caliber kit is pretty fool proof for fitting.
So let's start with the big boy..
Dual 63mm 3kw- Diagonal drive--
This is the beast of all setups and is strictly for the experienced rider- the power and torque on this machine is simply unbelievable and if I'm honest at time too much to handle..
This has to be in a diagonal setup the power in my opinion could not be used in a rear drive set up,the weight of the motors and the needed 10s battery make this a rather heavy board of over 9.25kg but it has awesome speed acceleration and range and the motors are never really running at any where near full power
Speed over 45mph
range ( with 10S 8000mah)- 10-18 miles
best used on a 38" deck and over
Dual 50mm 4kw -Diagonal Drive
This is in my opinion the perfect blend of good power ,braking ,weight and is my board of choice when i pick one up to ride..The 50mm motors have great torque whilst still only requiring a single 7s battery so weight is 7.25kg and again the diagonal drive gives better grip and braking as the front wheel is also braking - the motors are never overworked and rarely get hot
Speed- 30mph
range-10-15 miles (5800mah)
best used on a 36-38" deck
Dual 42mm rear drive
I first tried this setup on a short 33" deck and with 83mm wheels and 44T x12T gearing and it was a bit of a wheelie machine but i've since got it on a 37" carbon deck with 76mm wheels and 40Tx12T gearing it it just about perfect- the motors are tiny compared to the 63mm and only require a 6s battery ,even 5s for smaller riders or flatter terrain..Its got good acceleration and a top speed of around 25mph but the low weight is the killler app..under 6 kg.. Its a really good performer for the size but the motors do have to work pretty hard to get there..
Speed 25mph
range 6-8 miles ( 5000mah 6s)
best on 35-37" decks
As with all EV the speeds and range are all dependent upon the terrain and rider weight so these are only estimate from my experience..
I have never tried a single motor set up so i cannot comment on that but i would easily say a single 63mm motor would be more than capable of hitting 25-30mph with good acceleration ,Im just not sure about braking and grip-
Now to the Diagonal vs Rear dual argument..well for people looking for an everyday ,easy to ride setup the Diagonal drive wins hands down - Its got great grip with evenly distributed weight over each motor no matter where you are on the board,the push pull effect is very predictable and there's no chance of wheelies or rear wheel slides. The braking is also improved due to the motor at the front .
Now for people looking for bit of back end drifting and wheeling then the rear dual drive is for you it does carve quite differently to the diagonal drive and was a bit of a handful in the wet/dry conditions i tested in..I'm sure however somebody with a bit more skill than me could tame it easily..

 

[furp]

Nice comparison, thanks! Been waiting to hear your opinion of diagonal vs one axle drive for a while, glad I got my diagonal now. Really nice to see all the progress you made. I would love to get my hands on the latest firmware for the escs, where can I get it?

 

[beetbocks]

It's only compatable with the latest ESC I think .
Just give Bruno an email and he can advice ..