I am developing an off road wheelchair I just want to get back into the outdoors. I have put a Jazzy 614 on a six wheel chassis and rough hills trip the reset button. I need to replace the two 12 volt motors with something more powerful/torque. I do not know where to get motors and 24 volt controller for replacement. Can I get any help?
Here is a link to
There is insufficient information on the motors to be able to help. What is the model of the existing motor? What mounting is used? Have you contacted the manufacturer?
Weedpharma
Russell.
All wheel chairs and mobility scooters are 24V, your existing motors are 24V.
You need to checkout Burgerman's site: http://www.wheelchairdriver.com/
MarkT:
All wheel chairs and mobility scooters are 24V, your existing motors are 24V.
While that Jazzy is a 24 volt model (I donate time and help a guy here in Phoenix refurbish donated powerchairs and scooters for re-donation to needy individuals) - I wouldn't say that "all" are 24 volt. Most are, in fact, probably the majority are. However, I have seen a couple scooters that used a single 12 volt battery for propulsion. They tended to be "odd-duck" devices, and we tried to steer clients to more standard chairs (well, as "standard" as these proprietary things are).
MarkT:
You need to checkout Burgerman's site: http://www.wheelchairdriver.com/
I second this.
What's likely happening is that the system senses the over-current from the extra mass in the system (thus higher currents, maybe more noise from the motor), and trips the shutdown error mode of the Jazzy's controller; these controllers are typically configured and built to be very conservative in how they work - looking at them wrong will cause them them to trip.
Sometimes, you can get around the issue by reprogramming the controller - changing some of the parameters so that it can tolerate or lessen the current issue, or whatever is tripping the system. This is generally only possible with a special programmer device (or cable and PC software) - as such, they are typically only sold to service techs (and generally only those licensed to repair a particular manufacturer's models). These devices, as such, are not cheap - not by a long shot (unless you get really lucky with a craigslist ad or something). Sometimes you can find them on the open market (ebay, craigslist, hamfests) - but be prepared to spend some money. Also - not all programmers can program all models; the connector might fit, you might be able to change some parameters, or none of them - even though the programmer seemingly "works" with the chair's controller (that is, the programmer recognizes the controller, shows a version message, etc - but doesn't do anything else). Yep - this whole thing is one giant proprietary cluster - just the way the chair makers like it (and really - its for the user's protection - the chairs are built and designed to be, first and foremost - safe for the user, to the point of a fault - chair manufacturers can only get certified as AMA medical devices if they have this level of total control).
If the above isn't an option, your next best bet then would be to use a third-party motor controller, and built your own controlling system; an Arduino could help here (indeed, many of these wheelchair controllers and joysticks use ATMega8 and other Atmel uCs in them). The motor controller to use will depend on the current needs of the wheelchair; you can measure the windings of the motor to help determine that, but a quick and dirty way would be to look for any fuses from the battery to the controller; use that as your "low end" and you'll be safe.
For a controller - for something like this that you want to be reliable - I typically recommend using Vantec or Roboteq controllers. They both offer dual-motor brushed-DC systems; Roboteq is the most advanced of both (which you will pay for) - both brands aren't cheap, but they are both reliable and robust for this kind of purpose. At my friend's place, he actually built a 6-wheel drive platform using wheelchair motors and a Vantec; it works pretty well. We're currently working on a 4WD chair, too - which we'll probably use a Vantec controller there as well.
Both controller brands feature a wide range of options and methods to control them - both are easily controllable with RC servo signals, for instance (you can use the Servo library with the Arduino).
Finally - if you are tempted to re-purpose/re-use the wheelchair's original joystick, keep in mind that you may have to do some hacking/reverse engineering - unless you are lucky and can find or otherwise obtain a datasheet on the joystick; this is because most of those sticks today are either inductive or capacitively coupled; some also use hall-effect sensors. Only the really old ones will use potentiometers, as these would tend to get dirty at the contacts, leading to failure in a short period of time as the chair was used.
I am developing an off road wheelchair I just want to get back into the outdoors.
If you have use of both hands (or two ganged joysticks for a single hand), you might consider going with two tank style joysticks. Might simplify the setup and give better control in rough conditions.