Hello Dave,
what I am designing is a go-kart with 'universal' hand controls for disabled drivers, in particular for tetraplegic drivers. I am not designing the system around one particular driver, I want it to be accessible to any disabled driver with an interest in go-karts.
Having said that, I am at the very first stages of the design process, and I thought I might share some product design specifications with you, so that you have better idea of what I want to acheive:

1)I am using a 125cc clutched go-kart. LGK is a go-kart company from Italy which is willing to give me a hand with manufacturing and is actually providing a chassis and engine (www.lgk.it).

I'd try to design something that can be sold as a kit and suitable for all or nearly all karts, so it can be fitted easily and quickly, then removed so the kart can return to normal. That way, existing karting tracks could buy sets and when a wheelchair user comes along, they can fit the controls quickly. Marketed correctly, this will bring new business for them but it's all about cost - how many rides will it take to cover the costs of buying your kit... and if it's too complicated and unreliable, and hard to fit/remove, then this will put buyers off.


2)I want to keep things as simple as possible, therefore I would like to avoid power steering and lots of electrical aids. This is related to costs and ease of maintenance. However, my product should be the result of what the average driver wants.

It takes a fair amount of power to turn the steering on karts, and to operate the brakes and accelorater, so it's either some sort of servo-assisted set up or levers, which tend to be big and in the way...


3)The controls should be integrated in the steering wheel. I know that there are few existing products for disabled go-kart drivers and I do not want to 'reinvent the wheel'. I want to design an ergonomic steering wheel which will include 'easy-to-use' controls for the throttle and brake. The steering wheel radius should be larger than usual to reduce the amount of force required to turn the kart. I am hoping to make the steering wheel remoevable.

This is the area to focus on. I've seen several different designs, one being a handle-bar set up. The system we used was designed by a Dutch paraplegic guy that specialises in this, Hans van Schjack...

http://www.crosskart.nl/aangepastkarten.php


4)The seat should have a higher back support and should be covered with some padding material to avoid pressure ulcers.

Padded covers are easy to fit and remove, wash, etc.

The upper-body needs support so this is what we used...
http://www.tillett.co.uk/index2.html


5)I will include seat-belts and leg supports

Leg supports are easy - padded supports for ankles/calfs with velcro straps.

With the above rib-cage support, which could be re-designed and made adjustable so it can be easily and quickly adjusted to different drivers, would mean you won't necessarily need seat belts.



6)The steering column should be adjustable: length and angle.

I think this could be a problem/safety issue - check this out. Don't really see this as necessary.

Hope this helps.


I have much more to say but I dont want to write my entire thesis on this post!! Any comments or suggestions?
Francesco

thats all fine for strong arm tetras but someone like me with no pecks, tricepts, or hand control is poor.
with todays brake master cylinders you could do a simple side setup, using push for gass and pull to apply breaks on 1 lever which you strap the drivers hand to. to steer you could gear it to be easier and use a larger steering wheel with a tripin then no matter the tetra you can drive give me a chassis and motor and Ill have a working model by feb 08

I have built a few small buggies and found that a handle bar set up works great. I use a twist throttle and the master cyl. of a dirt bike. The handle bar maybe 12 inches across and I also have a quick disconnect on the handle bar for ease off access.

ted

Hey,
I would like to use a motorcycle brake master cylinder with my steering wheel controls, can anyone suggest any models? Has anybody ever used a bike master cylinder on their kart? Thanks

Tim, where do you race the kart?

theo

hi thare sorry about the spelling . not verry good with thi should have went to school ha. yes you have a dilema ,i am t4-5-6 after motox disaster 3 years ago one year ago i bought an f1 chassey with a 6 speed tmk9 125cc engin when i can i go raciing at my lockal trak, i made hand controls for it but i have good arme and hand muskles stil have to be lifted in and out but well wothe the fun . choped steering wheel and mounted throttle barrel from motorcykle . went to push bike shop got long thin gear change cable and small soldernes cable for other end . went to m-p for clutch lever that fitted straight on to clutch cable . then bought a hiabusa brake mastercylinder £70 x2 off mounted that to the reer of the wheel . got the local welder to mate the levers together in a u shape the went todemon tweeke to get the fittins to join mastercylinders togrther and the brabeb pipe and duble banjo tothen go to a vw pollo rear master cylinder that is fitted inside a pice of 2 inch box with one end blanked off soe onley one piston moves remove th foot pedle and use that for a mounting poit mastercylinders varey in type use the one that look like kelgat ones to much to explane but will get back to you tomorow with a photograph but it still needs a good grip to control.

cant youse this to save my self. well try again.i said that i would send pictures ,well here thaye are not. verry good will send some better ones later . ps it workes well for me .

a good friend of mine makes and sells some really nice kart controls. check them out at:180psi

I'm a c5 complete. So I'm relying on my mum and dad to be my hands. I didn't get much done on it last year. But I hope to have it done by the end of this year 2008. I'll be starting on it as soon as the warmer weather is here. Its only gone to be a fun kart, so I won't be racing against others, but I'll hopefully use it on a local track. However, saying its only a fun kart, it is a twin engine GX200 Pro Kart. (ex rental, so built like a brick outhouse ) I needed something heavy to hold the rally seat I've put in it.

The kart is stored away at the minute. But as soon as the weather warms up i'll be back at it. Hopefully in the next 4 weeks. I'll be using a leaver set up, rather than the wheel. the seat is like this one.
http://rallynuts.com/motorsport/Racing_Sea...s_Seat_1791.asp

But a cheaper one off ebay.