super offroad wheelchair

[Libertad87]

Hello im on a wheelchair but i live straignt in the country side, mud hill river etc. I just bought an attachment of a 20 inch fat bike 1500 w handbike electric, if i go up hill its really slippery and i still need a push. I would love to add a rear motor, im thinking about two hub with 20 inch fat or 24 mountain bike tyre. Im a bit confuse on controller and display...
I,ll need 2 controller and 2 display (its will be triky 3 display to get sync etc) can i just program the controller or i need a display all the time on?
thanks for help
My inspiration is the mtw by triride but not my budget!

 

[2old]

Pictures would help, but you might need 10 posts to be able to include (or someone could assist you in doing it. I'd be happy to, but don't know how).

 

[AdR]

There are single side motors. Each motor needs it's own controller. There are controllers that don't need a display to operate once programmed. Check out ebikes.ca. leaf bike motors. Some companies make dual vesc controllers. Spintend is one.

 

[Libertad87]

I was aiming to buy leafbike single side, can I get some examples of controller can do double hub with one display

 

[A-DamW]

... can I get some examples of controller can do double hub with one display

VESC based controllers can do this natively.

As long as they have can-bus(I never seen a VESC based controller without can-bus) they don't even need to be "dual" controllers.

You can string an arbitrary number/model of controllers together, and control all of them in concert.

I have seen 4 wheel drive skateboards with 4 individual controllers.

For displays, there is an "official" display:
VESC DISPLAY

You can also use a phone, iPhone/Android as a display, and setup/programming interface, if you have a bluetooth module, or a VESC-Express.

I know of at least 6 different projects using off-the-shelf cheap display hardware, none of them are quite production ready, but close.

ES member stancecoke, wrote some code to use some common e-bike displays with a VESC controller, I don't think this code has been pushed upstream into the main VESC codebase, but I bet it will be soon.
VESC - Flipsky 75100 V2 with Bafang Display and T15/T17 BB-Torque Sensor

I know y'all are going to get tired of me saying this, but the VESC ecosystem is an absolute swiss-army knife when it comes to motor controllers and peripherals.

 

[Chalo]

I was aiming to buy leafbike single side, can I get some examples of controller can do double hub with one display

You don't need a display. If you want one for whatever reason (depending on what you want it for), maybe only one of the controllers gets a display and the rest run without one.

To join multiple controllers to a single throttle, join all three throttle wires to one controller, then only ground and signal to all the other controllers.

I assume you need reverse operation. If you use a controller that has a reverse switch function, then you could use a multi pole switch to engage them all at once.

 

[Libertad87]

With a throttle with 3 controller they need to have the exact same settings to be sync?

 

[Libertad87]

I would activate the rear motor only up hill, how to have more torque and less speed

 

[Chalo]

I would activate the rear motor only up hill,

Then you should use a separate throttle for the rear motors. I'm not sure what the advantage would be of not using all your motors together whenever you are moving.

how to have more torque and less speed

More amperes of current will provide more torque (up to the motor's maximum). Lower voltage or higher motor winding count will result in lower RPM.

 

[MxusMick]

It won't be as clean, but maybe you could bypass the controllers all together and use brushed motors or permanent magnet treadmill motor with a belt or chain drive. Those motors operate on whatever voltage you feed, so wouldn't be confined to a low voltage cutout. The hoverboard could be a cheaper 3 phase McGyver option. Lots of disabled people really need something like this to live better, best Wishes!

 

[Libertad87]

i start to be a bit confuse about all option, just a question on the exotek 4 wheel motor (the best for disable person) EXOTEK
the rear motor is a chain and the front a hub, i want to be sure to get enough torque uphill how to understand wich single side shaft is ok for me?
thanks

 

[SlowCo]

Your wheelchair should have a second rear axle in the back to move your rear wheelchair wheels backwards to get more weight on the front motorized wheel. If possible, move/mount the front wheel closer to the wheelchair to shorten the wheel base. Then lower the tire pressure and upgrade or tune your controller and, if needed, your battery pack for more amps. Some Statorade in the hub motor to help shed heat is wise also.

 

[Libertad87]

Ok thanks to everyone for the moment I weld a plate to put my 2 fat wheel wheel without motor, is more backed so it's working really better. I have a sw900 display and general controller chinese 26 amp. I would love to have more torque.. so its 1500w hub they are three pas grade it's only max speed or there s something about torque. The higher it's the stronger I saw 2v till 4v. It's volt per cell? What's the meaning. I'm really use with solar system cell lithium. But new with e-bike techno

 

[SlowCo]

You could lace a smaller rim on the hub and use a lower tire so that the overall diameter is reduced. That equates to 'lower gearing'. But once the torque is greater than the grip of the tire can manage, you'll have to shorten the wheel base to get more weight over the front tire.

 

[Libertad87]

So you propose mechanical change nothing electric,?

 

[SlowCo]

So you propose mechanical change nothing electric,?

I don't know what your abilities are regarding your handicap or technical skills and how much help you can get to try a few things first.

I use a purely manual handbike with an extra rear axle to mount my wheelchair wheels backwards. That helps with putting more of my own weight towards the front driven handbike wheel. I don't know if such an extra axle or mounting points are available for your wheelchair.

I live in the Netherlands which is very flat but even I have traction problems sometimes when trying to get up a bridge especially when it's wet. And that is on pure muscle power/torque. To get up a longer slope I need to shift down to first gear and keep some pace to get up there.

As you have a direct (non gear) hub motor you can not shift down for more torque. The only way to get more torque from your set up is more (phase) amps from battery pack and controller and "gearing down" by using a smaller rim and tire. The cheapest way to try this out on your existing set up is to do a shunt mod on your controller if it's not programmable and put a smaller (less wide) tire on your rim.

You now have a fat bike tire on there. If it's a 20x4.0" tire it is probably a ERTRO size 100-406 (please CHECK!). There are other 20" bicycle tires that fit the same diameter (406mm) rim but are less wide (something in the 55-70mm range might fit your rim):


A 2.20" to 2.80" has a little less circumference and thus a little more torque.
To get more grip you should not have too high of a tire pressure. The tire should be on the soft side.
If you have the ability or help to shorten the tubes that attach your handbike closer to the wheelchair it will place more of your own weight towards the hub motor wheel. Even a few centimeters will help a lot in gaining more grip.

Best next modifications would be to mount a programmable controller and have it push more (phase) amps into your hub motor. That is if your battery pack can handle that and I would advise to use Statorade to help keep the motor cool enough. A smaller (16" bicycle) rim and tire to reduce the overall diameter of the hub motor wheel would be very helpful as well. If you google photos of hub motor wheels for wheelchairs you'll find that most have (much) smaller rims and tires than yours.

Good luck.

Here's my "acoustic" rig:

 

[Libertad87]

Thanks you so much!! I did weld rear axle it's changed a lot not slippery at all. I'm studying how to bring the front wheel closer.. now I reached the full power of the controller up hill on really heavy slope... But it's a 26 amp generic controller with a 1500 w hub... Look too less for me when Im up hill at 1200 w around the controller block..my battery is a 20 ah with a 40amp bms.
Any controller or idea to get the full torque out of my motor uphill

 

[MxusMick]

A smaller, wider wheel, like the other guy said, more like a wheelbarrow, you may find a salvage kids stroller with some small mags.