Joy Stick controlled go Kart

[DWheel]

Does anyone have plans for a joystick controlled Go Kart? My son is in a wheelchair but is able to drive his chair without a problem. I would love to build him an go kart that was fully controlled by joystick?

Your thoughts or input would be appreciated.

 

[itsid]

you mean a drive by wire?
like a computer joystick...
or a stick drive with mechanical linkages?

the electrical approach will be quite difficult to achieve, possible, but very difficult;
mechanical linkages might be easier, then again they require a lot more force.

IDK what your son is capable of, so hard for me to give any good advice other than this one:

if you need an electrical system (joystick) to move the kart you need to perfectly make sure that each and every part of it is redundant and has a crap load of error-checking and plausability checking in every single loop with an emergency shutdown/override enabled at all times.
An old wheelchair can help (taking the controller / joystick and some other parts from that)
to have all that nasty code chcking covered right from the get go.

You wouldn't want to have your kid in a kart that heads straight to the open road unable to steer or decelerate.
Not to mention you'll need some beefy motor to steer in the first place (and a big enough battery to power it)

Anyways, be sure that we'll try to help you as good as we can;

but frankly, I've seen an offroad wheelchair someone build for his wife (and now making them for clients as well) pretty expensive, but a tested and known to be safe product... maybe that's a better idea *shrugs*

A mechanical system can be set up more easily and maybe even more reliably,
but again, that depends on your boy's capabilities.

'sid

 

[DWheel]

Thanks Sid

I believe from your description it is drive by wire. I do have an off road wheelchair, but due to height much easier to flip than a go kart. Got several used wheelchairs that I can pull the controllers from. My only experience is building/adapting wheelchairs for him (hiking and beach).

I have no idea how to hook them up regular motors or what motors can be used for go karts and easily converted to electric go cart motors. What rims would i be looking at? I have been meaning to do this for a while, but no idea how to go about it.

He can drive a power wheelchair with no problem. So I was going to take the controller from the wheelchair. His right arm has enough strength to control a joystick, left arm minimal usage (legs zero), so when he lets go of the joystick the go kart would need to come to a stop.

 

[itsid]

Any motor that's covered by the controller can be used to even power the go kart.. you'd need to adjust the gearing to compensate for the additional weight compared to a wheelchair (thus you'd end up with less speed)

same goes for the steering, if the controller in question was meant for low speed small wheel steering, you'll likely need to add some oomph to reliably steer a gokart (especially if it's not a road kart but meant for some light offroading [aka back yard fun ])

I'm sure you'll have dozens of questions, but asking about the wheels now is a bit premature..
as long as you do not know how to even power the kart for your son, not to mention steering it.. the color isn't too important, is it
Rims depend on the tyres you want/need...

Personally I'd say it might even be worth looking at a gasoline engine instead of a DC motor.
that way you have all the forward momentum you'll need for sure;
Simplified down:
In the end, you'll be building a pimped up wheelchair with a wider track and a longer wheelbase.
If you keep the wheel diameter and the overall weight somewhat identical to the original wheelchair you'll be good with all the motors and controllers you currently have on said wheelchair.
if you increase wheels or weight you need to gear down (slower) or have a more powerfull motor.

But how about that:
tell us what you have in mind more exactly
race kart [unsuspended, small wheels with slicks],
yard kart [unsuspended, slightly bigger wheels with knobbies, a brush guard],
buggy [suspension, big wheels, a serious rollcage]..
something inbetween...?

And if possible show us what you have to work with (the controller, the motors etc.)
that gives us a better idea where to start.

Maybe what speeds you'd like, if you want/need something I cannot think of at the moment (like some sort of additional medical equipment or a remote control or something)

The more info we have to work with the easier it'll be to help

'sid

 

[DWheel]

Thanks some good questions. Let me do some pondering on it.

Here are some pictures of two wheelchairs that i have built with help. One is off road/hiking wheelchair. The other is for the beach.

http://s1230.photobucket.com/user/DWheel1/library/?sort=3&page=1

 

[itsid]

Oh see that I haven't had in mind... wheelchairs use differential steering like a segway ...
hm, a gokart will be hard to make, I doubt you'll get much closer than that first pic you have.

maybe something like the Amphicat or maybe a tracked vehicle...
but a go kart will be nearly impossible to achieve with differential steering; so those controllers are not going to work I'm afraid

Anyways.. tell us what you want, and maybe we can brainstorm with Nick a bit (you should've met him in your other thread)
to see what we can do about it

'sid

 

[Toycrusher]

Personally I think your chair with the gray flotation tires is the way to go. Just stretch the wheelbase to make room to lower the seat. Might have some traction and steering issues but still the easiest way to go

 

[bluetangkid]

I would think that with some software work with a raspberry pi you could read the joystick and output a pwm signal to make the kart go forward, and the side-side motion could be sent to a smaller controller to make the steering work. It could be done, but I wouldn't want to do something like that as I have no experience with dual controller stuff with a raspberry pi. I would talk to a robotics person, as I have seen and plan to do stuff somewhat like this for a BB-8 robot i plan to build. I would be making things that do not have humans in them, however.

 

[Dirt Devil]

Hi, me and my son built a go kart and it is very stable, controlled with a joystick and can raise and lower that might help for transfers into and out of a wheel chair. I added some pictures and a video in the project section. A link to the video is below.

https://youtu.be/EJNuHFu40vE

 

[itsid]

that's the thread I was thinking about as well when I just saw your video.

Soooo, since you're here now ...

tell us about the details of the kart (no ...the DETAILS!)
what controllers, motors are used, how many batteries.. how's the joystick wired...
you know everything that'll help DWheel to make one for his son.

'sid

 

[DeathMachine]

Since you have experience with electric wheelchairs and their joystick type control, why not steer it like a zero-turn mower? Front wheels are just big caster wheels, and it uses the differential steering from the drive motors.

Essentially, a stretched and widened wheelchair that he would sit in instead of on top of.

Heck, I have all that stuff from an electric wheelchair someone tossed out, might just do this for myself.

 

[Iron John]

It might be challenging to calibrate the sensitivity of the steering controls as speed increases, since there will be no 'feel'. Maybe you can program a response curve. How fast would you like the kart to go?