Converting to dual motor setup (Electric-scooter-wheelchair build)

[toebs]

Hi,

I am a manual wheel chair user.
I have converted an electric scooter (Aovo Pro S3), so that i can attach my wheelchair to it and go for a ride.
(Heres a video, not me, but of a somewhat similar concept by Erik Kondo)

It works very well, i use it often to comute 13km each way, i can go in rotating doors, public transport and so on.

However part of the conversion was to remove the rear wheel and ad two rear wheels, so the scooter can stand by it self for when i moun/unmount it with the wheel chair.

Therefor the scooter is fron-wheel driven. This means traction is not always super, since most of my weight is in the rear.
My idea is to buy an electric skateboard/mountain board gulwing-engine set and attach to the rear, instead of the standard longoard gulwing and wheels i have now.

This means converting to dual engine. I suppose i need a new controller, or y splitter? And maybe something else to ensure that the power is distributed properly to both the front and the rear engine.

I am ok with electronics, but being pointed towards some obvious steps would be really helpful

 

[From-A-To-B]

Hey there! Great project - eager to see how it comes out.

Yes, you’ll need 2 controllers to drive two motors. You can use one battery as long as it’s capable of meeting max power requirements for all the motors being driven. It’s possible to Y the throttle wires, but this can be fiddly and frustrating— others have written and problem solved about why this is, but you’re setting yourself up for success if you buy two identical controllers.

 

[toebs]

Hey there! Great project - eager to see how it comes out.

Yes, you’ll need 2 controllers to drive two motors. You can use one battery as long as it’s capable of meeting max power requirements for all the motors being driven. It’s possible to Y the throttle wires, but this can be fiddly and frustrating— others have written and problem solved about why this is, but you’re setting yourself up for success if you buy two identical controllers.

Thanks.

So i get two indentical controllers, y-cable from those to the same throttle at the handlebar, same with brake lever, and y-cable power from the battery also to connect both controllers (given the battery can output enough current)?

 

[From-A-To-B]

Sounds to me like you got it!

 

[toebs]

The wiring standards seem to be a little different for electric scooter controllers and skateboard controllers.
So lets say I get something like this motor and another controller for the aovo s3, like the one that is already in the board.
Then hopefully the colour coding of the cables that go into the thigh black connector cable on the controller, that goes to the hub motor, will match the colour code of the cables coming from the skateboard motor.

Any idea what the names are of the different connectors we see on the units. Power cables are XT60 or XT30 maybe? What about the cable going to the motors, any good suggestions for suited connectors?

 

[2Phast2Delirious]

I advise utilizing a 48v 750w (max) controller with a 12.5 in hub motor. It is much quicker, more dependable, and you can easily scale curbs and ride off-road. I attached a random image of the scooter. These go for $800-$2000 new or around $250-$500 used... but I lucky found one on a local listing for $75 (dead battery). You easily attached this to your wheelchair. Mine came with front suspension forks with disc brakes.



I made an attempt to build a similar project for my Pops, but instead created a killer "off-road" full suspension 750w (brushed) mobility scooter.

 

[toebs]

#6 Thanks - looks interesting! Will be looking into something like that for the next project.
To upside of my current scooter is the nimbleness and that i can carry it on my lab, easyli lift into a car etc.

 

[toebs]

In terms of getting a controller for my two alectric skateboard wheels, i am a little puzzled.

One option is going with a dual controller designed for skateboards, however these uses a remote for the control.
BUT can it be hooked up to the display that is on my electric scooter (akin to this)?

 

[amberwolf]

Displays are usually not intercompatible between different modesl and brands of controllers. Data formats and which data gets sent is usually specific to the set that came together, and a different one of either probably won't work with a different one of the other.

If you can figure out the wiring without damaging anything, and the voltages of the signals are compatible, you can try it anyway, but it's unlikely to do all (or any) of what it did with the original.

 

[amberwolf]

Then hopefully the colour coding of the cables that go into the thigh black connector cable on the controller, that goes to the hub motor, will match the colour code of the cables coming from the skateboard motor.

Unfortunately, color is usually only an indication of color, and wiring between motor and controller may not match even within the same brand of parts. It's typical that black is hall ground and red is hall 5v, but even that isn't universal. The GBY signal and phase wires may not match up color for color to get the right phase/hall combination. If it doesn't work as expected matching colors, and it doesn't have a self-learn function, you may have to try swapping two phase wires until it spins the right way, and then hall wires till it runs quietly at normal speed offground with very low current.

 

[toebs]

Displays are usually not intercompatible between different modesl and brands of controllers. Data formats and which data gets sent is usually specific to the set that came together, and a different one of either probably won't work with a different one of the other.

If you can figure out the wiring without damaging anything, and the voltages of the signals are compatible, you can try it anyway, but it's unlikely to do all (or any) of what it did with the original.

Thanks, that makes sense. Dont know why I didn't think of that.

So I think I will try to see if I can use original type controllers to run these wheels.
All from the same display, using splitters to controllers.

Think it could work?

 

[2Phast2Delirious]

The most affordable & reliable dual motor controller on eBay is this one.

EBike Electric Bicycle Scooter Brushless Controller dual-drive LCD display Set | eBay

In the TRIP, long press Function boton: single trip clear. P2=Number of pole pairs setting. Short press Power botton, and press function botton: change the gear position. P6=Cruise/No cruise selection setting.

www.ebay.com

You still have to buy "single/dual" and "turbo/eco switches (around $25 for both)


Dual motors is an overkill for your setup. but eager to see the scooter setup when it is ready. Keep us posted!

 

[amberwolf]

So I think I will try to see if I can use original type controllers to run these wheels.
All from the same display, using splitters to controllers.

Think it could work?

If the display is meant to connect to two controllers, then yes.

If not, it will only connect to one at a time, becuase it can't receive data from two at once on the same wire and interpret it correctly.

There are a few threads around here over the years discussing two controllers with one display; at least one of them has tested methods of doing it by only having one controller send data to the display, while the display sends data to both controllers.

 

[toebs]

The most affordable & reliable dual motor controller on eBay is this one.

EBike Electric Bicycle Scooter Brushless Controller dual-drive LCD display Set | eBay

In the TRIP, long press Function boton: single trip clear. P2=Number of pole pairs setting. Short press Power botton, and press function botton: change the gear position. P6=Cruise/No cruise selection setting.

www.ebay.com

You still have to buy "single/dual" and "turbo/eco switches (around $25 for both)


Dual motors is an overkill for your setup. but eager to see the scooter setup when it is ready. Keep us posted!

The Dual motors is to get traction, since the front wheel slips/skits a lot, especially uphill.

Thanks for the link. With one of these I guess I should be able to control the hub front motor and one electric skateboard wheel in the rear.
A little step down from my vision of 3-wheel-drive, but a good step up from 1 wheel drive I guess

 

[toebs]

If the display is meant to connect to two controllers, then yes.

If not, it will only connect to one at a time, becuase it can't receive data from two at once on the same wire and interpret it correctly.

There are a few threads around here over the years discussing two controllers with one display; at least one of them has tested methods of doing it by only having one controller send data to the display, while the display sends data to both controllers.

Ok makes sense.
I guess I could just test concept of having 2 skateboard wheels in the back is even useful, by putting a regular electric skateboard kit on the rear, and operate the remote control throttle with my left hand and the original front hub control with my right hand.

Buuut would pretty much just be an mvp

 

[2Phast2Delirious]

The undersized wheel or the way the scooter is mounted are most likely to blame for the loss of traction. The front wheels should carry all of the weight. I hope this helps.

 

[toebs]

The undersized wheel or the way the scooter is mounted are most likely to blame for the loss of traction. The front wheels should carry all of the weight. I hope this helps.

Hi,

Yes the loss of traction is because of inadequate weight on the front wheel. However this is hard to modify for me. Because I cannot move the wheelchair any more forward (the wheelchair foot plate sits against the front steering Coloumn), and the center gravity of the wheelchair is designed to be very far back (this is so it is easier to make wheelies and go over curbs, gravel etc in the wheelchair)

 

[eMark]

Instead of 40-50 psi in the front tire try 25 psi for improved traction. The inner tube should last longer before springing a leak as long as you have at least 25psi. It's no fun replacing a failed inner tube.

Nice Looking ...

You may not even need to use a tire guage. Just let out enuf air so the tire has a little give for more road surface contact and better traction. Sometimes its hard to get a good psi reading unless your a motorhead mechanic.

 

[amberwolf]

Many wheelchairs (but not all) have moveable axle-mount plates (or multiple axle holes in a welded-on plate) so you can customize the wheel placement for particular user's needs (longer or shorter arms, etc). If yours has this and you don't need the wheels as far forward for hand operation, you can move the wheels back as far as they will go (if they aren't already), to help put more weight on the front wheel.

If yours doesn't have this but you can modify it to do this, it will do the same thing.

Some look like this (I used these on one of my big-dog / cargo trailers; they came off a Quickie wheelchair)

https://endless-sphere.com/forums-old/download/file.php?id=43744

 

[amberwolf]

Per his request, G8rwood's project moved over here

Electric-assisted Wheelchair build ideas

Working on a similar project for my brother. Temporarily removed footrest and casters (spare chair) with a dropped bracket to clamp on scooter sides And going up chair tube. Front traction is an issue and up hill is terrible. It was just an exercise on functionality. He is currently on...

endless-sphere.com