Electric Assist Unicycle Build
Electric Assist Unicycle Build
Hey Guys, not too much time to write much now, but here is a photo collection for one of the projects I finished and have with me in SF for the Maker Faire this weekend, which might be of interest to some on this forum. The goal was an electric ASSIST unicycle made from a direct drive hub motor. A unicycle that you can ride normally, but with the advantage of power going on the uphills and regen on the downhills to save your knees in both cases.
The implementation should be pretty self explanatory from the CAD section view:
The implementation should be pretty self explanatory from the CAD section view:
Last edited by justin_le on Jul 19 2016 3:35am, edited 2 times in total.
Reason: Typo in title - fixed corrupt image
Reason: Typo in title - fixed corrupt image
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Unicycle Side Plates
Side covers started off as 9" x 9" by 1/2" thick aluminum plates from Metal Supermarkets, and are mounted to the rotary table for machining:
Bulk of metal removed with a large diameter hogging bit:
And press fit cavity for ball bearing too:
Bulk of metal removed with a large diameter hogging bit:
And press fit cavity for ball bearing too:
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Side Plate Finishing
Inside corner of side plate rounded with a ball nose end mill:
All the spoke holes and mounting holes are drilled out on the spoke flange, which is part of the side cover plate rather than part of the rotor.
All the spoke holes and mounting holes are drilled out on the spoke flange, which is part of the side cover plate rather than part of the rotor.
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Unicycle Side Plate, outside
After this, the inside surface of the side cover has been finished, so it gets taken off the table, flipped over, and put back on for machining the outside surface.
The flange is milled down 2.5mm thick, exposing all the spoke holes, and the rest of the cover is faced off just for aesthetics.
Outside is finished with a 3/8" corner radius bit for a nice rounded edge: And finally, the side completed plate is parted off with a small 3/16" end mill:
The flange is milled down 2.5mm thick, exposing all the spoke holes, and the rest of the cover is faced off just for aesthetics.
Outside is finished with a 3/8" corner radius bit for a nice rounded edge: And finally, the side completed plate is parted off with a small 3/16" end mill:
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Re: Electric Assist Uniycle Build
The spindle for the cranks started off as an off the shelf cotterless unicycle hub from UDC:
One of the flanges was machined right off, but the other flange left in place as a means for coupling the pedal cranks to the motor casing via the right side cover. The spindle diameter in the middle just happened to be exactly 20mm already, which was the size of ball bearing that I had going over it.
One of the flanges was machined right off, but the other flange left in place as a means for coupling the pedal cranks to the motor casing via the right side cover. The spindle diameter in the middle just happened to be exactly 20mm already, which was the size of ball bearing that I had going over it.
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Left Side Cover
A second side plate was machined just like the first, only this one was made to fit a much larger 45mm ID thin section ball bearing to go over the aluminum stator support:
- Attachments
-
- Left side side cover, houses 45mm ID thin section ball bearing
- UN Large ball bearing cover.jpg (50.88 KiB) Viewed 11841 times
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Unicycle Stator
The stator was taken from a Nine Continent hub motor that was having hall issues. My plans had the stator bored out to a 46mm hole. However, you can see that if this is done, it would completely eliminate the welding on the center tube that holds the two stamped steel plates together. In order to keep things structurally sound, I first cut some small steel tubes and welded them to three of the "speed holes" that are punched out of the support plates in order to hold the halves together after the center was cut out:
Then the original axle hole was drilled:
And then bored open to exactly 46mm:
Then the original axle hole was drilled:
And then bored open to exactly 46mm:
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Re: Electric Assist Uniycle Build
The next step was the aluminum stator support, which plays the important roll of preventing the stator from rotating by being affixed to the unicycle frame, and of holding the stator centered in the hub even with the spindle on which it rests can rotate.
Starts off with 3" diameter 6061 aluminum from a scrap yard: A fair bit of machining to get her down to size: Close to the final shape: And the completed unit after parting off. The 6 holes are to bolt to the actual Nine Continent stator and lock it from rotating. Need wire slots for phase and hall cables too, so these are milled into the 45mm bearing support:
Starts off with 3" diameter 6061 aluminum from a scrap yard: A fair bit of machining to get her down to size: Close to the final shape: And the completed unit after parting off. The 6 holes are to bolt to the actual Nine Continent stator and lock it from rotating. Need wire slots for phase and hall cables too, so these are milled into the 45mm bearing support:
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Rotor
The metal rotor ring and magnets were also made from a returned Nine Continent motor, in this case one that had suffered water damage.
The stock Nine Continent rotors are a little heavy, with a 7mm thick steel ring for the side cover bolts, and a pretty thick aluminum casting over top of that for the spoke flange. Since I had the spokes coming off the side plate, none of this was needed and I could shave off a lot of superfluous metal:
In the end, I took the steel ring down to about 2.5mm thick, reducing the original rotor weight of 1.78 kg down to just 830 grams:
The stock Nine Continent rotors are a little heavy, with a 7mm thick steel ring for the side cover bolts, and a pretty thick aluminum casting over top of that for the spoke flange. Since I had the spokes coming off the side plate, none of this was needed and I could shave off a lot of superfluous metal:
In the end, I took the steel ring down to about 2.5mm thick, reducing the original rotor weight of 1.78 kg down to just 830 grams:
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
- vanilla ice 100 MW
- Posts: 2778
- Joined: Sep 05 2007 9:15pm
- Location: socal dude
Re: Electric Assist Uniycle Build
Hardcore work there.. put some gyros on it!
All the pieces, and assembly
Here is what all the bits and pieces looked like after quite a few late nights in the shop:
Stator is pressed on and bolted to the machined stator support: Spindle is inserted into the right hand side plate, and original spoke flange bolts to a small aluminum spacer ring so that turning the cranks turns the hub in 1:1 ratio: Steel rotor ring with the magnets is snapped onto this side cover and then held snugly down with 9 bolts clamping the edge. This is needed to hold it secure against the magnetic forces with the steel stator is inserted. Otherwise the 2.5mm steel ring isn't strong enough to stay round, and the force of attraction causes it to wrap around the stator and deforming into an oval shape.
Even then, it was a bit tricky to get the stator in: After that, remaining side cover plate with the 45mm ball bearing is pressed in place over the wires.
Stator is pressed on and bolted to the machined stator support: Spindle is inserted into the right hand side plate, and original spoke flange bolts to a small aluminum spacer ring so that turning the cranks turns the hub in 1:1 ratio: Steel rotor ring with the magnets is snapped onto this side cover and then held snugly down with 9 bolts clamping the edge. This is needed to hold it secure against the magnetic forces with the steel stator is inserted. Otherwise the 2.5mm steel ring isn't strong enough to stay round, and the force of attraction causes it to wrap around the stator and deforming into an oval shape.
Even then, it was a bit tricky to get the stator in: After that, remaining side cover plate with the 45mm ball bearing is pressed in place over the wires.
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Finished Wheel
Here's a couple shots of the built up wheel, after lacing into a wide 700c rim:
I've got the wheel mounted in a Kris Holm 29" Frame with a big apple tire. The little battery rack at the back was made from angle aluminum and holds a pair of Hobbyking 5Ah LiPoly packs and an infineon 25A controller. Handlebar off the seat is home-made and has the CA, a throttle, lumenator light, and ebrake lever all attached to it:
I've got the wheel mounted in a Kris Holm 29" Frame with a big apple tire. The little battery rack at the back was made from angle aluminum and holds a pair of Hobbyking 5Ah LiPoly packs and an infineon 25A controller. Handlebar off the seat is home-made and has the CA, a throttle, lumenator light, and ebrake lever all attached to it:
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Re: Electric Assist Uniycle Build
WOW... Thats amazing Justin, quite a post after what seems like a long-time-no-see!
How does it ride so far?
Brilliant design, and I can't wait to see how the stabilizer circuits you are probably about to design for it turn out
How does it ride so far?
Brilliant design, and I can't wait to see how the stabilizer circuits you are probably about to design for it turn out

On a dusty pew in a vestibule sits the Devil playing pocket pool, he's waiting for the next poor fool who forgot that it was Sunday
STABLE:
HI-V (Retired); Sun Cruiser w/ Hill Topper Kit; Giant Simple Cruiser w/ Amazon 1000W Front Hub.
Parts donated by Rassy and Greenerwheels have made many of my builds possible, THANK YOU!!!
STABLE:
HI-V (Retired); Sun Cruiser w/ Hill Topper Kit; Giant Simple Cruiser w/ Amazon 1000W Front Hub.
Parts donated by Rassy and Greenerwheels have made many of my builds possible, THANK YOU!!!
- liveforphysics 100 GW
- Posts: 14137
- Joined: Oct 29 2008 1:48am
- Location: Santa Cruz, CA, USA
Re: Electric Assist Uniycle Build
So nicely done and so cool! I can't wait to see the videos!
Each carcinogen vapor exposure includes a dice roll for cancer.
Each mutagen vapor exposure includes a dice roll for reproductive genetic defects in your children.
Each engine start sprays them into a shared atmosphere which includes beings not offered an opportunity to consent accepting these cancer experiences and defective genetics life experiences.
Every post is a free gift to the collective of minds composing the living bleeding edge of LEV development on our spaceship.
Each mutagen vapor exposure includes a dice roll for reproductive genetic defects in your children.
Each engine start sprays them into a shared atmosphere which includes beings not offered an opportunity to consent accepting these cancer experiences and defective genetics life experiences.
Every post is a free gift to the collective of minds composing the living bleeding edge of LEV development on our spaceship.
Re: Electric Assist Uniycle Build
Ebikes.CA for the win.
It's so great to see people that are THIS passionate

It's so great to see people that are THIS passionate



World Record: http://endless-sphere.com/forums/viewto ... =3&t=61893
Ebike Nerdcast: http://www.endless-sphere.com/forums/vi ... 18&t=19548
Maxwell Motorbikes http://www.maxwellmotorbikes.com
LED "Ballast" Charging http://endless-sphere.com/forums/viewto ... ng#p752060
ebikes.ca!Buystuff!
Ebike Nerdcast: http://www.endless-sphere.com/forums/vi ... 18&t=19548
Maxwell Motorbikes http://www.maxwellmotorbikes.com
LED "Ballast" Charging http://endless-sphere.com/forums/viewto ... ng#p752060
ebikes.ca!Buystuff!
- liveforphysics 100 GW
- Posts: 14137
- Joined: Oct 29 2008 1:48am
- Location: Santa Cruz, CA, USA
Re: Electric Assist Uniycle Build
Was the Honda electric unicycle a source of any inspirations for your project?
Each carcinogen vapor exposure includes a dice roll for cancer.
Each mutagen vapor exposure includes a dice roll for reproductive genetic defects in your children.
Each engine start sprays them into a shared atmosphere which includes beings not offered an opportunity to consent accepting these cancer experiences and defective genetics life experiences.
Every post is a free gift to the collective of minds composing the living bleeding edge of LEV development on our spaceship.
Each mutagen vapor exposure includes a dice roll for reproductive genetic defects in your children.
Each engine start sprays them into a shared atmosphere which includes beings not offered an opportunity to consent accepting these cancer experiences and defective genetics life experiences.
Every post is a free gift to the collective of minds composing the living bleeding edge of LEV development on our spaceship.
- Toorbough ULL-Zeveigh 100 MW
- Posts: 2598
- Joined: Feb 09 2007 3:02am
- Location: Marlboro
Re: Electric Assist Uniycle Build
nah, bet it stems all the way back to wishing for one of these when he was a kid.
sued.
correct me if i'm wrong, but it looks like ur doing all the machining by hand, no cnc.
i found every step useful & directly applicable to various projects, none of which are a unicycle.
it'll save me a lot of frustration having ur pictoral roadmap for a guide, it's greatly appreciated.
be careful or u might get correct me if i'm wrong, but it looks like ur doing all the machining by hand, no cnc.
i found every step useful & directly applicable to various projects, none of which are a unicycle.
it'll save me a lot of frustration having ur pictoral roadmap for a guide, it's greatly appreciated.
- amberwolf 100 GW
- Posts: 31081
- Joined: Aug 17 2009 6:43am
- Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
- Contact:
Re: Electric Assist Uniycle Build
What, no panniers?
Just kidding--every time I think I'm creative I see stuff like this. 
Those mountain passes are gonna be easier without the rest of all that bike weight this time around, right Justin?


Those mountain passes are gonna be easier without the rest of all that bike weight this time around, right Justin?

If you found this advice helpful, supporting contributions are accepted here.
"if it ain't broke, improve it till it is"----Dog-Hauler Cargo eTrike SB Cruiser----The HI-Lebowski: a Lebowski SMD brain running a zombified Honda IMA Inverter: a HOW-TO guide----Cargo eBike CrazyBike2----General Blog
"if it ain't broke, improve it till it is"----Dog-Hauler Cargo eTrike SB Cruiser----The HI-Lebowski: a Lebowski SMD brain running a zombified Honda IMA Inverter: a HOW-TO guide----Cargo eBike CrazyBike2----General Blog
- Drunkskunk 100 GW
- Posts: 7245
- Joined: Apr 14 2007 11:37am
- Location: Dallas, Texas. U.S.A.
Re: Electric Assist Uniycle Build
Wow. Thats Amazing!
Buy the ticket, take the ride.
Monster Bike:http://endless-sphere.com/forums/viewto ... =6&t=38667
Monster Bike:http://endless-sphere.com/forums/viewto ... =6&t=38667
Re: Electric Assist Uniycle Build
Very nice job, Justin! Amazing what you can do with a 9C! It would be so easy to enlarge phase wires with that large bearing!
Dave
Dave
Re: Electric Assist Uniycle Build
Super sick man!! Video with burnout please!!
I've gotta make it to one of the Maker Faires sometime, great to have someone like you representing the ES scene. Thanks for sharing.

I've gotta make it to one of the Maker Faires sometime, great to have someone like you representing the ES scene. Thanks for sharing.
Four wheels moves the body, Two wheels moves the soul
Thanks to Justin @ http://www.ebike.ca He brings the soul to ES
Thanks to Justin @ http://www.ebike.ca He brings the soul to ES
Re: Electric Assist Uniycle Build
That's neat! Can't wait to see the video.
I'd probably kill myself trying to ride one of those.
I'd probably kill myself trying to ride one of those.
Take it easy... but take it. (Woody Guthrie)
my eTownie build thread: http://endless-sphere.com/forums/viewto ... =6&t=23701
Magazine article https://www.electricbike.com/nicks-etownie/
my eTownie build thread: http://endless-sphere.com/forums/viewto ... =6&t=23701
Magazine article https://www.electricbike.com/nicks-etownie/
- bzhwindtalker 1 MW
- Posts: 1792
- Joined: Dec 01 2008 1:03pm
- Location: Lyon, France
Re: Electric Assist Uniycle Build
unicycles are cool, ebikes are cool.
electro unicycle is cool²
adam
electro unicycle is cool²

adam
Re: Electric Assist Uniycle Build
That's correct, there wasn't any CNC used here, just a standard milling machine with a rotary table. I installed a digital readout system on it a few months ago though which was invaluable though, especially for getting all the ball bearing fits on the first pass. The first few side covers I experimented with by turning them on a lathe, but for something of this large in diameter it was a bit tricky and the rotary table with large milling bits was faster and perfectly accurate.Toorbough ULL-Zeveigh wrote: correct me if i'm wrong, but it looks like ur doing all the machining by hand, no cnc.
Well glad it could be of use. Will be curious to see what these various projects up your sleeve are!i found every step useful & directly applicable to various projects, none of which are a unicycle.
it'll save me a lot of frustration having ur pictoral roadmap for a guide, it's greatly appreciated.
Justin
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Re: Electric Assist Uniycle Build
So far, with just a throttle and an ebrake for regen this one works surprisingly well! You don't go especially fast on a 29" unicycle, my cadence tops out around 20-22kph, so with the electric assist I am only averaging just over 1 Wh/km, and for every amp-hour I use going up hill, about 0.5 Ah goes back into the pack on regen from the downhill. So that little 36V 5Ah LiPoly battery is good for over 150km at this rate. I'm at 70km right now and haven't charged it yet.dequinox wrote:WOW... Thats amazing Justin, quite a post after what seems like a long-time-no-see!
How does it ride so far?
The control loop with a thumb throttle controller PWM isn't ideal though, and it will be much better when I finish a custom controller that is motor phase current regulated. That way between the throttle and the brake you can dial in the exact torque on the hub which will stay constant regardless of speed, rather than always adjusting up and down on the throttle as your speed changes in order to maintain the same torque. On a unicycle, you have other things to think about, and so having to hold and focus on the throttle for every change in the road or change in speed is a bit consuming.
So, you are right about this too. In the original plan, I thought it would be great to have self balancing circuitry on the electric assist uni - no throttle and you lean and pedal to accelerate or brake. I also thought you could use it as a 'trainer' device, to make it easier to learn, and then gradually turn down the amount of electronic balancing as you get more comfortable riding. That was the idea at least.Brilliant design, and I can't wait to see how the stabilizer circuits you are probably about to design for it turn out
The circuitboard was made to fit in the same enclosure box we use for the CA production, running a PIC18F series chip to take the signals from a rate gyro and accelerometer and then use that to drive a 4 quadrant controller:
I struggled for several days with the code trying to get this to work, but found that to have both human operated pedals AND a balancing control circuit running at the same time resulted in the two always fighting each other. The harder you pedaled, the more you injected a disturbance that the motor would correct by braking, and if you tried to stop or pedal backwards then the motor would kick in high gear going forwards. It was a really strange experience, like riding through a viscous fluid where the harder you worked the more resistance you faced.
As somebody who rides a unicycle, the only way I could make it work was either to turn the self balancing gain way down, so that I was basically able to overcome the motor and keep it steady with my legs, or I could turn the balancing gain way up, remove the pedals and just rest my feet and let the electronics do everything. As soon as you had pedals, and the motor, and the balancing circuitry, it was chaos.
I did bring a 2nd orange 24" electric unicycle down to the Maker Faire which had the balancing circuitry to show people though and to see if maybe someone else could figure out the right human/electric mix with it.
But again it was most rideable with the pedals removed, and since my intent was electric assist this wasn't the end that I wanted. That's why in the larger 29" uni, I left the balancing purely to the rider, and the motor is purely there as an assist and a brake, and that seems to work much better. At least for now, there is still a lot to explore here. -Justin
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled
Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled