Bounder chairs

[paranon]

http://www.wheelchairs.com/pdf/brochure ... medium.pdf
does anybody have any experience with these chairs? From the brochure it looks like they are the closest thing on the market to a BM style chair, and from the size of the battery box it looks like a lithium conversion would be pretty straightforward if range was a problem.

[Burgerman]

With the fat tyres, its hugely wide. Whole chair is very heavy, batteries hanging out of the rear. Looks very dated. Big square ugly controller but it works well according to users. But at least they do their own stuff rather than just buying in the usual industry components and bolting it all together.

Adding a lithium battery is exactly the same on all chairs. They even offer one. But its of limited capacity if you use a grp 24 sized battery box, or huge and hanging out if you use a grp 27 sized box. And uses a generic BMS which means its not going to give you the range or longevity you can get from lithium setup done properly.

But if you want ready to go and no DIY there isn't any option. I just wish they would modernise a bit!

[cavetta]

I have been using a Bounder H-frame with 24 group batteries for almost 10 years. They are rather heavy and bulky but they are still good for indoors and when programmed to you needs it is very good indoors, outdoors, climbing 2 to 3 inch curbs etc. Going back 9 years the wheelchairs had a speed of 4 mph or similar. I hated slow speeds and that was one of the reasons I considered a Bounder. Mine has a standard speed of 9.1 mph which is enough for me. It is very expensive but it is also reliable and offers many customisations. I researched all the wheelchairs and found many shortcomings in all of them, I only found the Bounder that accommodated most of my needs. I wish they would make them more modern, a bit shorter etc. but as I said there are no wheelchair that will completely satisfy you. Before the Bounder I had a power wheelchair with a speed of 4 mph and I always hated that speed, moreover the Bounder is much better with all the options and customisations they offer. Also today with all the improvements and innovations claimed by manufacturers I still can’t find a model better than my Bounder.

Now I hear they are manufacturing an ultra high performance model that is 48V and has top speed of 24 kph. I hope other manufacturers will also manufacture 48V models and hopefully we will have some real improvements in power wheelchairs.

[Burgerman]

Well I am not too sure but I think they are experimenting rather than offering a 48V setup. And it even be a consequence of reading these pages over the last 5 years.

My own chair uses a 45V setup, (47.X Volts charge, 43V running voltage etc) for 16mph. (8.5mph motors on double the voltage)
And the reason for them trying going to "higher voltage" is the same as the reason I did it.
Lithium doesn't suffer from voltage sag (peukert) in the same way that lead does. So a smaller Ah but higher voltage battery becomes workable with the same peak Amp draw. At least quality high rate cells don't if the capacity is maximised too.

So instead of making the gearing taller - the usual way to increase speed - which reduces torque/increases battery Amp drain in direct proportion. You can just increase voltage and double the speed without any range, torque, downsides. A huge efficiency win of about 100% that seems impossible on the face of it! But its really true. It works because the controller is actually an electrical "gearbox". If you do the maths it behaves exactly as it should.

My chair is here: http://www.wheelchairdriver.com/BM-MK3- ... rchair.htm

[Amadeus]

With the fat tyres, its hugely wide.Whole chair is very heavy, batteries hanging out of the rear.

I do own a Bounder H frame. It is rather a bit longer than wide.

Looks very dated. Big square ugly controller but it works well according to users. But at least they do their own stuff rather than just buying in the usual industry components and bolting it all together.

Definitely, Bounder is one of the best power chairs I ever tried. It requires extensive programming but the performance of the chair is great. The speed is just unbelievable. Even though it works well indoor, this chair seems to be made for active users outdoor. The motors and the controller are so powerful then I wouldn't recommend such chair to someone who enjoys only smooth riding and quick controller response. Hard to find such chair in Canada.

[Sully]

Paranon, Get the price tag on the model you most desire, then see if you are still interested. But from all indications, you will get a good product for your money. Ask yourself if your insurance or other medical finance scheme cover this chair? Now if you can afford it outright, just put all these issues aside, and buy one, and then you tell us just how good it is.

[Burgerman]

They need to lighten it, stop making from gas pipe tube! Make them look a bit less old fashioned. Stop the battery sticking out of the rear, move the rider off the front wheels and make it less nose heavy. And modernise that square control box so it doesn't look like a shoe box. Then I would buy one. And narrower so it isn't too wide once the fat tyres are fitted.

[Sully]

Don't you think that moving the seat back to over the rear wheels and taking the weight off the front wheels would kind of solve the battery sticking out of the back as well? Of course a chair designed for maximum LiFePO4 capacity would resolve all these problems and width as well.

At least one of their models has huge front mounted motors and either chain or belt drive. This pushes the batteries back and has to increase front wheel weight. Your BM3 design seems to accomodate all these problems in one solution, the BM3.

[Burgerman]

Quite...