E-mail discussion about the ALBER ADVENTURE powerchair

> Hi John,
> I was looking through your website, and I was hoping for some advice,
> I have a nerve disease called Friederichs Ataxia which means I use a
> manual wheelchair mainly because I'm a student and thus haven't got
> that much spare money but also because I am quite stubborn really.
> Anyway due to increased fatigue and the recent addition of a Canine
> Partner assistance dog (Vogue) I have realised I really need a
> powerchair but I had a PDQ Powertrike and had a very bad experience
> and so I would really appreciate your advice on powerchairs. I need it
> for outdoors as that's where I have most problem pushing myself and
> obviously now I need to exercise Vogue too.

> I have used a Invacare Storm and got really frustrated with it for
> many reasons, especially as the pins that held the footplates in place
> kept breaking. I have trialled the Alber Adventure powerchair
> (http://www.gerald-simonds.com/flash/index.html) which really has a
> too good to be true spec but not being too technically minded I find
> it quite hard to judge and was hoping you could advise me whether you
> think this is suitable for what I need.
>
> I really hope you can help. Many thanks in advance.
>
> Anna Pettman
>
> Alber Adventure spec
> Ground Clearace 17cm
> Turning Circle 88cm (64cm without footrests)
> Climbing capability 18%
> Batteries Lead gel 24volts/22Ah x2
> Automatic Battery Charger with automatic swich off and conservation of
> charge
> Range 45 km (apparently this is possibe because the motors are in the
> rear wheels)
> max loading 140kg (I weigh 65kg)
> total weight 96.7kg

Hi,
Website is big on talk and "design" but no real details at all!  Another
case of flashy design being more important than the information and some
real detailed specs.

Just to look at it the first thing that I think is that the seat (c of g) is
too far forwards for good control, manoeuvrability and battery life. So I
would be very wary of the (usual) fine control issues.  So for my own use at
least the hacksaw would be used already!  When you reverse to a wall the
first thing to touch SHOULD be your head.  This means its short enough to
turn around in small corridors and loos etc.  My own chairs are like this
after some modification, but most are not.  This chair looks quite long
behind you, so not good in this respect but no "real" specs to look at.
I would need to cut those anti tip wheels off to start with, they are in the
way!

Next important thing is battery size.  This is important. But again no info
but yours!  22ah though is extremely small  Most outdoor type chairs use 70
or 55ah ones, and they are often not big enough for my usage.

It matters because range, speed and performance is all a big careful balance
on a powerchair.  e.g.. A 6mph chair needs a minimum 56ah batteries to go and
be useful all day long.  A 4mph chair can manage on 40ah ones and still
manage a days use because the gearing is lower and so less current is used
most of the time

I find their range claim very dubious!
OK so the motors are in the rear wheels (probably brushless and obviously
gearbox free)
Brushless motors are the way ahead. they are superior.  They allow a
powerchair to have a little more range on a given battery than the same
chair using normal motors.  But we are talking about a SMALL improvement in
efficiency here. at best say 10 to 25 percent more efficiency.

So for a 6mph chair used all day hard as I use mine you might just about get
away with say 45ah batteries in place of the 55ah ones.  JUST!
I don't see how 22ah ones could possibly cope.

When a manufacturer makes a range claim its really best to ignore it.  I
can think of lots of chairs specs that claim 25 miles range regardless of
the chairs speed and gearing.  In reality you may get 10 in real use, in
real streets in the 6mph version and 13 or so in the 4mph variants.

To get the best range you would drive in a straight line on a hard totally
flat airfield at constant speed until the powerchair stops. (which
incidentally ruins its batteries permanently)  Turning uses lots more power.
As does driving along a cambered road, especially with a nose heavy chair.
Never mind carpets and ramps, or manoeuvring about indoors!!

In addition discharging batteries really deeply drastically shortens the
life so erring on the big side has longevity benefits due to less deep
discharging on a daily basis.

Weight (yours and the chairs) matters too! This info helps decide if a given
battery size or motor/speed/control system will be any use!  Obviously a
child gets more range and performance from a chair than a heavy adult would
do.

Controller make and amp rating?  Unknown.
Programming unknown.

So really its hard to know without a lot more real construction and parts
specs and details.

Burgerman