The ultimate mod...my buddy in a wheelchair needs some help!

[deadhead]

OK so a friend of mine is a paraplegic.  His wheelchair controller recently broke and he is going to lose his job if he can't get the thing fixed.  The wheelchair repair place tells him it is $1500 for the controller.  All this thing is is a joystick that controls the motors.  It is not just on/off, it controls the speed as well, though he said in a bind he could control the speed of the chair from another switch.

I was thinking there has to be a better/cheaper solution to this problem that a bunch of robot guys have already solved   Anyone know of a better way to do this? he has a laptop, so if he could buy some type of usb controler maybe and use software to control the motors through a port?  Any ideas sure would be appreciated.

[Rebelgium]

Designing a controller (which will have to use a technique called PWM) for such heavy motors will be quite advanced and expensive.
Not nearly 1k5$ but still...

I think it's much easier work with the existing controller and find out what part isn't working.
And then fix it ...
 


What is your knowledge on elektronics?

[airman00]

OK, hope I'm not too late

Get a USB Phidget Interface Kit and connect to the outputs a motor driver for 2 40A motors. Reply back if you want more information


OR go on ebay, buy a motor controller that is rated for your friends wheelchair motors and replace it with the current controller. Please give us more info about the wheelchair so we can help you. Probably you can just replace the mosfet or maybe its just a fuse thats blown.
Give us details!

[reagentz]

I'm the friend in question, I can't find anything on my chair it's a Quickie Freestyle F11 chair, if you can find the .pdf file on this chair it should list the motors in them and the speed controls, if you do find the .pdf please link it for me because I can't find my books on the chair anywhere.

Oh and the wheels are mid-wheel drive just like a Segway. The lights on the control panel just started blinking there's 3 red, 4 yellow, and 3 green, all the lights were flashing but 2 of the green. OEM says it means "control lock" and there's no way to unlock it. My chair shop guy said that he knew someone who fixed the joystick on his and got it working. When you open the control panel box it's a solid state board, with a joystick wired to it with what looks like a small version of an IDE cable. You can't just buy the joystick from what I've seen it's manufactured by P & B Control Systems in the UK. Inside the joystick looks like an optical track ball mouse, with sensors and these little moving pieces off the joystick arm, on each little piece looks like a magnet that floats over the optical sensor to make it move whatever direction you move the joystick. I couldn't smell any burn spots on the board, the joystick seemed wore out.

I order the control panel to get out of my current unmobile situation but it was $1,500 bucks, I honestly think I can hook a laptop tothe chair and make it work much cheaper, I just need a cable that connects the laptop to the chair and software that can control the direction through a USB cable or firewire connection to the chair. I just don't know where to start, I've looked into automation control solutions but there's nothing tailored specifically that I've found for this. I worked in automation control some 15 years ago automating water dredges, but the technology moves as fast as PC technology so 15 years has been awhile to be out of the loop on new advances.

the motors on the chair work well, and I know there has to be some type of speed control because I had that wired into the control box panel. If I had the manual would help a great deal.

Thanks for all the input and thanks to my good friend deadhead for posting this and pointing me in some directions.

[airman00]

I've sued those types of motors on robots . Check the motor for any information. Usually there is a label on it. Right down everything it says on the motor and post it online.   Thouroughly check the wheelchair for information

[reagentz]

This is all I've manages to find on the chair itself:

Quickie Freestyle F11:


Controller P&G VSI 50(70):

[reagentz]

I'll get the chair back Tuesday I'll get all the info off the motors then.

[airman00]

so what are you trying to do now?

are you going to fix it , or add a laptop, or what?

[Soeren]

Hi,

[...] I worked in automation control some 15 years ago automating water dredges, but the technology moves as fast as PC technology so 15 years has been awhile to be out of the loop on new advances.

the motors on the chair work well, and I know there has to be some type of speed control because I had that wired into the control box panel. If I had the manual would help a great deal.

You should be able to build a simple PWM control for it then. I have used wheel chair motors for robots and it really doesn't take much, but the H-bridge will have to be sturdy of course.

What voltage does it use?
Can you follow a schematic diagram, make a PCB (if the outlay is provided) and build it up?
I assume you can get to the "raw" motor supply lines, i.e. that the blown controller is something exterior to them?

Please post any markings on the motors, perhaps that will help.

And don't even consider mixing a lap top into the equation, that would only make it so much more complicated during daily use - what you had worked, don't reinvent the wheel (chair)

[reagentz]

And don't even consider mixing a lap top into the equation, that would only make it so much more complicated during daily use - what you had worked, don't reinvent the wheel (chair)

Don't reinvent the wheelchair? what kind of statement is that? hah!

As to answer the above reply before this, I'm fixing my chair with the factory controller, but $1,500 just seems outrageous for what it is, I do believe making it work with a laptop would be so much better. The possibilities would be limitless once that could be done. This is just a priject I've given myself to work on, for now yea factory fix is quick and will get me mobile again.

My friend was orginally posting to see if anyone had hooked a PC up to their bot in the past and help get some direction as to what software to use to control it etc. When it come down to it I'm technically riding a bot frame, motors, batteries, only difference is its not with remote control and servos.

[reagentz]

What voltage does it use?
Can you follow a schematic diagram, make a PCB (if the outlay is provided) and build it up?
I assume you can get to the "raw" motor supply lines, i.e. that the blown controller is something exterior to them?

12v motors from the info i've looked into, don't have all the info on the motors yet, I do know the chair is around 250 pounds and supports me and I'm 6' 2" 240 pounds, also runs top end at 6mph on 10" wheels. I know there's an equation on here for that.

As for reading diagrams yes I can read them and draw them up. I have an A.S. in mechanical engineering and worked in automation controls for 2 years, I used a program called Paragon 500 to design touch screen interfaces for the automated systems we worked on. its just been 15 years since I've been in automation the technology is so different. I thought some of you guys who are hobbiests at this would know exactly what stuff I'd need to operate the motors through a computer, or at least point me in the right direction of a company who makes these parts. I know there's nothing out there exactly what I need, it will all be modified and custom work.

[reagentz]

On a side noted, speaking of wheelchair modifications, check this out for those who hasn't seen it:






This was built using the same chair assembly, and P&G VSI 50(70) controller with T-grip.

[airman00]

i've used a laptop on my bot
check my blog erobots.blogspot.com   it has info


A laptop on it would only add to it coolness, like programming the wheelchair to move on its own.

,Eric

[reagentz]

airman your link solved about half my issues, thanks so much I'm even more excited now and I have a few friends who can program the API for me.

[airman00]

My program is simple, if you want the updated version of my program email me.

Feel free to contact me if you have any questions whatsoever

,Eric