20th June 2019

Of wheelchairs and pricing – and a challenge to an open source hardware project

Here’s an interesting story that says much about the state of the “disability industry” (those companies that make and supply products and take profit from people with disabilities). Having lived in France for years the specifics described cover my experience here – but I know from experience that the details described apply everywhere.

A few months ago my assigned OT told me I should replace my 10 year old electric wheelchair. Despite its age and the carrying of a few battle scars and the recent need to perform a few relatively minor repairs (the leg hangers – the parts that support legs and feet had been damaged beyond usability) which were quickly and competently performed, it continues to provide satisfactory service. But, after now 10 years spending 12-15 hours per day, 365 days per year sitting in it during which time I have lost count of the number of seat cushions I have worn out it was firmly pointed out that the machine I depend on for my mobility is likely to drop dead at any moment. At the same time, with general age related health changes I need a wheelchair with a few more bells and whistles – in particular I need a wheelchair that can tilt, lift and recline its seat electrically and has leg hangers that can lift my legs into different positions throughout the day – the better to spread support of my body’s weight (no, I’m not fat!)

So, with few (if any) apologies to the manufacturer of the wheelchair shown in the picture above (I’m not naming them because my criticism here applies to almost all wheelchair manufacturers) …

What makes up a “modern” electric wheelchair?

In essence, a “modern” electric wheelchair – ie; one available in any specialist wheelchair retail outlet – (apart from the control electronics – to which I will return) would be familiar and could be constructed by a 19th Century blacksmith.

Universally they consist of:

  1. A mix of tubular and sheet steel, crudely welded and/or bolted together. This is not only the cheapest material from which to make a wheelchair, it is also by far the cheapest manufacturing method.
  2. A battery box is slung beneath the seat, large enough to carry two 12V truck-size lead acid batteries (invented in 1859 by French physicist Gaston Planté) whose combined weight is ~60Kg (~132 lbs).
  3. A crude chassis – which may take the form of a U-shaped tubular frame or a couple of longitudinal tubes joined by cross pieces (or the battery box) or something made out of angle-iron bolted together.
  4. However formed, the purpose of the chassis is to provide brackets from which hang the motors and castor wheels below and secure a seat above.
  5. The motors would be easily recognised and understood by Michael Faraday (born 1791) as they are crude brushed or brushless commutator driven coil and magnet devices with truly appalling weight and energy efficiency. In most models the motors can be seen hanging out in the breeze behind the drive wheels – manufacturers can’t be bothered to even spend money enclosing the gubbins.
  6. A seat – which varies from a crude foam cushion with a nylon back strung between two metal uprights to something that resembles an electrically adjustable car seat that you might find in anything but the most basic model in any current car manufacturer’s range.

So, a “modern” electric wheelchair is something that uses technology (materials and propulsion and energy) that our 19th Century forefathers understood and could have assembled from scratch.

Ah – but how about the controls? After all, manufacturers make much of the fancy control systems they install with 3 inch electronic displays that tell the user everything from the time and date to the speed they are supposedly travelling at.

I’ll touch on a teensy problem before moving on. Every model of electric wheelchair I have ever tried or used – rear-wheel, mid-wheel or front-wheel drive – has all the directional stability of a shopping cart with a wonky wheel. On anything but a billiard table smooth surface (which precludes any road or pavement of my acquaintance) anyone who takes their eyes away from their direction of travel for just an instant is likely to find themselves in a gutter, drain or – when pedestrians aimlessly ignore their approach or (yes, I’m talking to you, you self-important madams – PLURAL) continue walking towards an oncoming wheelchair expecting it to move sideways or disappear so that you can continue to exercise your absolute right of way – involved in a nasty accident.

Nasty accident? Perhaps now is a good time to mention that the wheelchair that was eventually configured and recommended to me weighs 180Kg (almost 400 lbs) – the one I’m sitting in weighed a more typical 150Kg when delivered. Add a moderately average adult passenger and the pedestrian is about to be hit by over a quarter of a ton of moving vehicle which, even if only moving at a walking pace, will cause severe injuries to the shins (as the footplates strike home) followed by either the pedestrian landing on top of the disabled person or the pedestrian being knocked over backwards, probably involving limb breakages and head injuries … even before the quarter ton of moving vehicle rolls over them like a tank.

Side issue rant over … Point is – no wheelchair user can possibly look at a multi-informational LCD display while they are driving along unless they want to be involved in an accident. It follows that such fripperies have no value and are not needed.

Could a 19th Century blacksmith really make a “modern” wheelchair?

Thinking back to my school days (around the age of 11 or 12) and early physics lessons learning about electricity – I constructed a working electric motor by winding a coil of wire round a piece of card with the wire ends left exposed, stuck a pin in each end of the card and hung this construction on a simple frame made of bent wire. Place a horse-shoe magnet over the coil and apply a battery with a few Volts to the bare ends of the coil and watch the motor spin.

“Advanced” (11.5 year old) electricity teaching – control the speed of the motor. Simple. Insert a varistor – ‘variable resistor’ (just like the rotary volume control on an old radio or TV – just a bit heavier duty) in series with the battery and voila! (as they say here in France) a speed controllable motor.

Varistors date back to Faraday as well so once again our 19th Century blacksmith could have controlled the speed of our theoretical “modern” wheelchair. Add a second motor, another varistor and a switch and you have electrical direction control (ie; no need for any form of tiller).

Before anyone adds a comment that varistors are extremely power wasteful and have the unfortunate side effect of getting VERY hot in use let me say “I know”. My point here is that, use of 20th century semiconductors apart a precise replica of a “modern” electric wheelchair could have been constructed by a 19th century village blacksmith.

Of course, “modern” wheelchairs have boxes with joysticks, buttons and colourful displays – which, the manufacturers are fond of telling, are connected to vastly powerful programmable computers that control the rate at which the wheelchair accelerates, brakes, turns etc.

Er … that would be a simple plastic box containing a microcontroller (trade cost about 50 cents) some commodity software … and a bunch of semiconductor devices called MOSFETs – basically electrical taps capable of controlling the very high currents demanded by the motors necessary to push over a quarter of a ton of mass (see how the “build it cheap” method starts to build up other problems?) without getting too hot or wasting too much battery power.

This (including the microcontrollers) is technology I was playing with in the 1970’s – or 50 years ago to put it simply.

Unless my marbles have completely left my skull we are now living well into the 21st Century.

Which begs the question, why are wheelchair manufacturers still producing products using technologies that are between 150 and 200 years old?

Could it have anything to do with maximising profits by using the cheapest possible materials and components, cheapest possible technologies, minimal R&D … and maximising sales pricing through market manipulation?

I’m going to give a straight answer (I’m only an FIoD and an FBCS with 40 years of top-level business and technology experience behind me so take my opinion for what it’s worth).

That is precisely what the disability industry does and how it behaves.

Back to my recent experience …

Somebody brought a new electric wheelchair to my home, quickly “configured it” (ie, they adjusted the width between the armrests and the depth of the seat base with Allen keys and stuck the velcroed on cushions in different places to give me the support I wanted) … and left it with me for a week. I have to confess it made a HUGE difference to the levels of daily chronic pain and other symptoms I had been experiencing in my old wheelchair.

That said … I confess I have one fancy car in my garage. Its front seats are fully electrically controlled (with memory settings for added convenience). These seats’ range of movements and other features include:

Whole seat forward and back

Seatback recline

Seat height

Seat tilt angle – front and rear independently

Adjustable lumbar support (electrical, remember)

Adjustable side cushion support (electrical, remember)

Back massage facility

Seat heating

Seat cooling (OK – the car has a climate control system so this is an unfair comparison with a wheelchair)

To top things off, the car seat is covered in sumptuous, hand-stitched, soft-skin leather. It is SO much more comfortable than any wheelchair I have ever sat in that I sometimes go into the garage and just sit in it as it’s better than any wheelchair at relieving the postural pain I experience.

And the price for all this luxury (from an exotic car manufacturer’s options price list)? 5,000 euros – for TWO seats … or 2,500 euros for one seat I would need on a wheelchair.

Now, remember this seat is unique to a car that is manufactured in annual quantities that are a tiny fraction of the numbers any self-respecting wheelchair manufacturer builds in a month. Yet the cost of a seat that fits a very wide range of human body shapes (I am well into the 5th centile of the range) and can be adjusted at the whim of its occupant to provide whatever support and comfort desired as well as being covered in buttery soft Italian leather.

Bear all this in mind as you read about seat pads fixed in place with strips of Velcro and seat cushions that require Allen keys to adjust the depth from backrest to accommodate different leg lengths.

Anyway, at the end of the week the people returned to collect the new wheelchair and I asked for a quote to buy one.

Here is where (unless you are also a user of electric wheelchairs and disability equipment in general) your jaw is about to hit the ground – fair warning.

After a couple of weeks (this is France and significantly this is dealing with the disability industry in France – why hurry just because somebody is in pain and has expressed an urgent interest in buying a product?) a quote arrived.

At the bottom of several pages listing just about every nut, bolt and washer and all the “accessories” I’d specified (like a seat) the final price was shown as …

27,000 euros

I’ll repeat – 27,000 euros. For an electric wheelchair built using 19th Century technology.

Oh – the price of the “seat option” configured with Velcro strips and Allen keys to fit my body shape and comfort at a single point in time accounted for HALF of that total price.

So … 13,500 euros buys a cheap steel chassis, a battery box containing two truck batteries, two motors, some cheap electronics, two drive wheels and four castors. The other 13,500 euros buys a cheap seat.

What on earth makes a 19th Century wheelchair worth 27,000 euros?

A comparison is in order.

Here in France I can buy a brand new BMW 116i car (price comparison taken from AutoPlus magazine – https://www.autoplus.fr/bmw/serie_1/prix-neuf/)- complete with fully galvanised and meticulously painted body, four doors, four seats (including electrically adjustable front seats), air-conditioning, electric windows, alloy wheels, an engine, a sound system, Bluetooth phone integration and sat-nav. The BMW will have been tested in the harshest climates on the planet over many months and built to comply with regulations defined by every possible market the car will be sold in. From scratch, say 4 years of R&D at a cost of millions of euros – before the first example is sold. To add insult to injury the BMW costs a whopping 4,000 euros LESS than the wheelchair.

What possibly justifies charging 27,000 euros – or, as we now know, 4,000 euros more than a far more complex and expensive to design, build and deliver upmarket super-mini?

If you ask the wheelchair manufacturers (I have) they will mumble about high R&D costs, vastly smaller markets, distribution costs … blah, blah, blah.

We could explore each of these arguments in detail but I’ll cut to the chase – NONE OF THEM ARE TRUE.

Take “high R&D costs”. Truth is they continue to sell the same 19th Century technology in a new colour year after year without spending (in relative terms) more than a penny on R&D. Yes, electric wheelchairs are subject to crash testing – but that is far less rigorous than the tests a new car model must pass and in any event, even dropping a top-of-the-range electric wheelchair off a cliff to see what happens to it would cost a wheelchair manufacturer less than it costs BMW to undergo a front wing crash test.

Take “vastly smaller markets”.

Really?

Point 1: in developed countries where people have the resources to buy and use “modern” electric wheelchairs around 3% of the population need them. Take the population of the UK alone – in 2018 ~67 million people … 3% = over 2 million electric wheelchair users. Across Europe there are approximately 6 million electric wheelchair users and in the USA around 10 million. Given the average wheelchair life of 5 years (being generous) and that’s a market for over 3 million electric wheelchairs each year.

Point 2: stop listening to what manufacturers say to their customers – listen instead to what they say to their shareholders (it’s easier than looking up their annual reports and formal accounts filings). For example, the small USA based manufacturer SmartChair (see https://kdsmartchair.com/blogs/news/18706123-wheelchair-facts-numbers-and-figures-infographic) estimates global sales of electric wheelchairs worldwide to be $3.9 BILLION – that’s $3,900,000,000 (about 3.5 billion euros). The independent Statista (https://www.statista.com/statistics/485637/world-wheelchair-market-volume-by-region/) estimates total wheelchair sales (both manual and electric) to be $5.6 billion in 2018 – an increase of ~90% since 2018

As for “distribution costs” – gimme a break. Is anybody seriously going to argue that it costs more to configure a wheelchair (cars get built with far more customer chosen options) and deliver it to a dealer than it costs to configure a BMW 116i to an individual customer’s desired options (many of which need deep integration into the vehicle’s on-board electronics and other systems) and ship it to a showroom from which it was ordered?

For 27,000 euros you’d at least expect a bit of customer service – right?

Before I can answer the question we should go back and look at the weight of the wheelchair proposed to me. Its weight before anyone sat in it is 180Kg, the equivalent of more than FOUR bags of cement or two-and-a-half average size men.

Understand what this means. Because of the cheap construction materials (heavy steel) and use of cheap, heavy motors and batteries the passenger (the sole purpose of the machine being to move around) typically weighs only around 30% of the total weight of the machine when in use.

Put another way, around 70% of the energy used by the average “modern” wheelchair is consumed just pushing the chair alone around and only 30% used to convey the passenger. It doesn’t have to be this way – a point I will return to.

The energy efficiency is only the start of a whole slew of problems .

  • In Europe the maximum carrying capacity set for wheelchair lifts fitted in publicly accessible buildings (shops, government buildings etc) is only 200Kg. When the lift is not marked (some helpful decorator painted over the ugly label) and you enter it innocently in your conveyance weighing over 250Kg in total the result is both inevitable and embarrassing to all concerned. I speak from experience when I say that after being helped by store or theatre staff into several wheelchair lifts – only to have them jam and lock solid after moving just the few inches necessary to lock the doors and imprison me – spending an hour or two idling the time away while the fire brigade arrives, destroys the lift mechanism and attaches a crane to lift me out of the darned contraption is no fun – for example, read about my experience at the Trafalgar Theatre in London I posted to the Bespoken disability forum at http://www.bespoken.me/forum/topics/trafalgar-studios-theatre-london-whitehall.
  • Care has to be taken even with ramps that many retail premises use to become “legally compliant”. I’ve bent and even snapped one or two in my time. Not pleasant to one’s safety or one’s spine!
  • And, we come to a big problem. In the 19th Century (when these wheelchair contraptions were designed) everyone travelled by horse and buggy. No problem – couple of stout planks and up you go. Problem is, these days most people travel by car – yet few, if any, wheelchair manufacturers give any thought to how their products might fit inside anything smaller than a 32 ton lorry or bus. You’d think it simple to fold a backrest – like the front seats of a two door car. Oh no! The manufacturers insist that such a thing is impossible- beyond the wit of man and far outside the scope of the feared crash testers. Except … yet again [sigh], none of that is true. The no longer available Otto Bock B600 (I have worn out two in my time) had a simple catch to release the electric recline mechanism from the backrest allowing the backrest to flop forward. The Luca Q I am sitting in has a push-pin release to do the same job allowing the backrest to flop on to the seat base. Why is this important? Because consumer vehicles (unlike commercial trucks and vans) are not designed to accommodate a full height wheelchair. So, if you live away from a town (as I do in splendid rural peace and quiet) and no buses pass your door you are kind of stuck in the house – unless you’d like to invest another 80,000 euros in an adapted (by which I mean somebody has lowered the floor and stripped out 70%~80% of the interior) van and rattle along happy to be out of the house but poor and growing deaf by the minute – because you are driving a van.
  • And worse it gets again. My personal integrated transport solution involves a top-of-the-range Ford Galaxy (minivan for American readers) whose rearmost (third) row of seats havs been removed to make way for a an AutoAdapt Joey tail lift (see https://www.braunability.eu/en/products/stowing-solutions/joey-lift/ for example) which, with the addition of a remote tailgate opener and a set of wireless controls gives me complete independence. As I am still (just!) able to drag myself from one end of the car to the other using the roof rails I’m sure Ford fitted for just that purpose I am able to press buttons to open tailgate, drive wheelchair on to ramp, drop seat back, fix restraining straps, drag myself to the driver seat and push buttons that lift the wheelchair into the car and close the tailgate. I cannot over-emphasise the value and importance that this means of independent travel brings to my life.
  • But … the Joey tail lift has a maximum carrying capacity of 157Kg … er … but the proposed wheelchair weighs 180Kg empty )not even counting the weight of the day-bag I usually strap to an armrest).
  • The Joey limit is entirely reasonable. Of course it would be possible for the company to fit beefier motors and components to carry more but simple physics dictate that a car’s 12V electrical system puffs out of steam at around that weight. The higher capacity lifts fitted to commercial mini-buses and vans rely on their 24V electrical systems to provide the energy required to lift a heavier weight.

The evidence that the manufacturer of the chair that was trying to be sold to me at a mere 27,000 euros had just started with a 19th Century design then, as more and more “modern” features were added (such as tilt / lift / recline seating and electric leg hangers) simply bolted more devices and more heavy outdated motors surrounded by even more heavy steel bars and boxes on to the thing is clear when you see that the empty device now weighed a not inconsiderable 180Kg.

Anyone with common sense can surely see that a wheelchair weight of 180Kg is beyond any sane person’s idea of reasonable.

The “solution” proposed to me was that I trade in my Ford Galaxy (that I am entirely happy with) for one of the aforementioned converted vans. Never mind the additional 80,000 euros cost – or the fact that in the conversion all the rear passenger seats are taken out and thrown away – leaving one of the biggest two-seat rattle-boxes on the planet.

So … customer service.

My proposed solution was simple and elegant. The wheelchair as specified had an empty weight of 180Kg – let’s say 190Kg if I wanted to retain the convenience of leaving my day bag attached.

Hmm … 190Kg – 157Kg = 33Kg too much!

Solution! Remove the 60+Kg of 19th Century lead acid batteries and fit 21st Century technology lithium batteries (actually LiFePo4 as they don’t catch fire or explode). A lithium battery providing more energy than the two combined truck batteries is both smaller than just one of the original batteries fitted and, at 9Kg, saves 51Kg of useless weight. Whichever way you look at it less weight is good. So, problem solved?

Nope!

The manufacturer and the dealer trying to clinch the 27,000 euros sale both came up with one crackpot answer after another in their hair-brained attempts to convince me that it was impossible to power a wheelchair with lithium batteries. They wouldn’t even accept the possibility when shown brochures of four-seat golf buggies and industrial fork-lift trucks powered by lithium batteries. Or the fact that small companies like Nissan, Tesla and every other car company on the planet is either already producing or has plans to introduce lithium powered electric cars with realistic 300~400 mile range and 20 minute recharge times.

My mind boggles!

I have some bad news for you chaps. Since we spoke I ordered a LiFePo4 battery pack from China, made and delivered to my exact specifications – output 29V (max), capacity 80Ah, maximum discharge current electronically limited to 100A (same as the 19th Century fuse fitted to my existing Luca wheelchair).

I then had a friend lift the 63Kg of original lead acid batteries out of my (long out of guarantee) wheelchair, constructed a simple connection panel incorporating a 100A circuit breaker in place of the metre of waste cable and twin 50A truck fuses originally fitted. This was then secured inside less than the space taken by one of the original batteries.

Result? Entirely as predicted. The wheelchair continues to operate flawlessly. I had the Chinese company supply chargers with XLR connectors to the same specification as the original Luca charger allowing me to charge the wheelchair using the original socket and needing no modification to the wheelchair or its electronics whatever.

The new lithium battery weighs 9Kg – so saving 54Kg compared to the original batteries. The wheelchair is as expected sprightlier (it not only has more power – higher battery voltage being part but lower weight being the biggest factor by far). Wheelchair stability is unaffected – there’s enough iron underneath my seat to keep the wheelchair glued to the ground – even when driving up, down and across slopes in excess of the manufacturer’s original specification, including very bumpy slopes with many hidden rabbit holes.

I have made no changes to the wheelchair’s programming (none have proven necessary). Its top speed remains regulated by the controller but it gets there far quicker (think sports car rather than lorry). It tackles ramps that it could not formerly manage as if they were not there.

Oh – and unlike lead acid batteries that have to be charged at least daily regardless of use if you want to get any life out of them, the lithium battery can be run to empty if required and still be recharged to full capacity. As a test, I used the wheelchair following my usual routine for a week – at which point the battery indicator lost one bar. I then recharged it and by measuring the charging time calculated I had used ~80% of the battery’s capacity – though I was unable to detect any drop in performance.

So, the only “negative” to report is that the battery indicator is now inaccurate – and if that bothered me it wuld be but a few minutes work to reprogram with the new parameters.

Anyway, thanks to the appalling service I was shown a 27,000 euro sale was lost, I have been proven right and whatever wheelchair I buy next will instantly be fitted with a lithium battery pack.

And I will not be paying 27,000 euros for it.

What are the problems evident here?

  1. The majority of the products on the electric wheelchair market are nothing more than washed-over versions of products the manufacturers were selling in the 1970s and earlier. The technologies used in their design and manufacture are at least 50 years old and for the most part between 150 to 200 years old.
  2. The prices demanded for the products are quite simply outrageous. They bear no relationship to “R&D”, production and distribution costs plus a fair markup. They are based on the maximum amount the companies can force out of a disabled person’s bank account – pure and simple. Once you are paraplegic, like me, you have to have a wheelchair – these companies know that and, far from being the caring, solution seeking, life-enabling cuddly mom&pop stores they pretend to be they are rapacious rip-off merchants living off the backs of some of the poorest members of society. It may have become obvious to anyone reading thus far that I am in the envious position of being able to write a cheque for 27,000 euros should I feel it justified. But the vast majority of my fellow wheelchair needers are not so fortunate. Why else do you not see the 2 million people in need of electric wheelchairs in France as well as the UK in your local supermarket or the desk next to yours in the office?
  3. PR nonsense aside, there is no significant R&D conducted by the few big global and European electric wheelchair manufacturers. Such innovation that does appear comes only from smaller companies – and if their products find a successful niche in the market they are simply bought up by one of the larger players – only for their innovative products to gradually be withdrawn from the market as the big players continue their business of getting fat on their old, overpriced products.

What solutions come to mind?

Business issues

I think the disability market – certainly across Europe – is long overdue for a competition review followed closely by strict regulations on the behaviours exhibited by the big players. There seems ample evidence of predatory practice (of the kind airlines used to get up to before regulation put a stop). There also seems ample evidence of a lack of competition leading to overpricing and consumer abuse.

Use of new technology already here

While the big players in the electric wheelchair market act like King Canute – trying to hold back the tide of progress by refusing to or proving incapable of investing in new technologies and buying up – only to squash – any company that produces even a hint of a worthwhile technological progress – newer startups are showing the kind of things use of modern technology can do.

Taking one at random (as I happen to have purchased one of their FoldaWheel models over three years ago) the Malaysian company Wheelchair88 (https://www.wheelchair88.com/) makes modest use of well established current technologies to produce solutions to real life problems faced by disabled people.

I’ll first talk about the FoldaWheel wheelchair that I purchased. Anyone who knows me well (or follows my meanderings around the Internet) will know that I have a life-long passion for Maserati cars and other Italian exotica. For decades I spent much of my life driving and racing these machines. As soon as I became paraplegic all that came to a crashing halt for two reasons: first, I can no longer operate a clutch so driving any manual gearbox vehicle is out of the question and second, there is no way any sports oriented (or even conventional saloon or SUV) can carry a full size electric wheelchair – even if you find one where the backrest folds.

So, how to get back behind the wheel of a Maserati and carry an electric wheelchair?

The first part of the problem is easy – modern Maseratis can be fitted with F1 style “paddle-shift” sequential gear selectors – so actually driving one is within my capabilities.

The second part of the problem was solved by the FoldaWheel. In brief, this is an electric wheelchair that:

  • is constructed from lightweight aircraft-grade aluminium – stronger than steel yet a fraction of its weight
  • is designed to fold like a baby’s pushchair – in about a second it can be transformed from an adult size electric wheelchair into a compact “cube” that can be stowed in a normal size car boot
  • Uses lithium battery packs to provide more than adequate energy for an energetic day’s use
  • Uses direct drive motors (actually inside the wheelhub – no power-sapping gearboxes
  • I have three battery packs fitted to mine – yet the entire machine weighs only 26Kg empty – so my wife can easily lift it in and out of the boot (trunk) of a standard saloon, hatchback or SUV.

The company offers other innovative products including wheelchairs that lift the occupant to a standing position (very important for both health and socialisation – unless you’ve ever tried to engage in discussion with someone at a party while sitting down when everyone else is standing yu may not understand the problem) and even a model that offers four-wheel drive and can climb stairs – the very bete noir of the paraplegic.

As for durability and endurance (a factor I’m sure the 19th Century contraption peddlers will call into question) my experience is that, while I don’t use the FoldaWheel I have every day – or anywhere near that – I have subjected it to fairly extreme use. My approach to wheelchairs is that they are supposed to be an aid to allow me to take part in any event or action that I want to do. So … I have had this wheelchair carry me across miles of heavily cobbled streets in France, Germany and across Europe, used it to climb Norwegian mountain paths and goat tracks in the Pyrenees – tackling tree roots, pot-holes and rocks in the process, climb ridiculously steep ramps as well as do all the usual daily activities of someone travelling around – such as tackling broken pavements and the jokes that many municipal authorities count as pavement ramps – which often end in sudden drops into deep gutters. After all this abuse I have to say I’m impressed. The chair still folds and unfolds as it did when brand new. It has not a single loose bolt or joint and emits not a squeak – though unsurprisingly, given the treatment I have just described, the motors occasionally make a clicking sound suggesting that a bearing is on its way to failure. Having found a source of the motors it uses on Alibaba at a delivered price of a few hundred euros I am about to purchase a couple to keep in the car against the day when a motor might fail – at which point the excellent design of this wheelchair will allow me to replace the faulty motor in the middle of a busy street armed with nothing more than an Allen key and a few minutes delay to whatever I’m doing.

Now, let me say that the company’s products are far from perfect. The FoldaWheel I have is too small for a tall European male (I was 6’4″ – about 1.93 metres – tall when I was standing) so I can only use the device by placing two deep foam cushions on the seat base. The device has no suspension to talk of and no support for either legs (mine flop outward unless restrained) or upper body lateral movement. Translation – it’s not the most comfortable wheelchair in the world.

But … look at the specifications and compare them to the huge 180Kg behemoth most of this article has been discussing.

Most importantly it enables me to travel around in a car I love, visit places I would never get to using my 19th Century design behemoth and provides a very useful backup to my everyday wheelchair whenever it fails or needs to go in for service.

Because of its light weight (about a quarter of my body weight) the energy efficiency is turned completely on its head. Its motors are only 150W each (300W) in total. For those of you not good with electrical maths let me explain that at full power this wheelchair only consumes around 12 Amps – compared to the 100Amps of the “modern” wheelchair I’m sitting in. Yet it has a higher top speed and I can vouch for its sprightly behaviour. Its maximum range with three small lithium batteries fitted is 39Km (24 miles) [on an ideal, flat surface – real world performance, as for all wheelchairs, will be lower) easily out-stripping the wheelchair I’m sitting in. It delivers better performance while using only 12% of the energy of a 19th Century design.

Pricing, profitability and value

And finally, we turn to the price. My example, complete with three batteries cost me about 3,000 euros delivered to France.

And let’s turn to a closer comparison to the wheelchair recently proposed to me at a cost of 27,000 euros. This Malaysian company does not offer a directly comparabale model but does have a range of standing powerchairs (that from the established manufacturers would be even more expensive than the the one with seat tilt/lift/recline proposed to me – a typical price in France for such a model would be well over 30,000 euros). From the Malaysian company? Around 10,000 euros delivered to my door. Around one third of the price of a comparable machine from one of the big manufacturers using their 19th Century technology.

How has this Malaysian company managed to pull off the trick of delivering better products that respond to real world problems and manage to sell them at a fraction of the price charged by companies peddling 19th Century products?

First let’s look again at how big the price difference is. Were I to, say, take a budget of 27,000 euros and spend it with this Malaysian company I could buy their most expensive folding wheelchair, standing wheelchair and stair-climbing wheelchair (three wheelchairs in all) and spend only ~21,000 euros including delivery to my door. I am obviously not going to buy three specialised yet compromised wheelchairs. My point is the differences in both the enabling function of these new products and the vast difference in value.

I think there are three main factors at play here that enable the company to perform as it does:

  1. a willingness to embrace new but significantly currently available technologies to deliver products with a step-change in performance compared to existing 19th Century designs – 8-fold energy efficiency, greater speed and durability being just some of the attributes
  2. response to real-world problems faced by their customers – while I’d still describe the company’s products as “one trick ponies” (ie, no single model covers the range of requirements I describe below) and all suffer the universally common faults of having nowhere to hang a day bag (big hint, wheelchair manufacturers – it isn’t possible to get your hands into trouser pockets and if you really think it’s practical to fold yourself in half to reach a bag slung under the wheelchair which you can only reach by stretching your legs then start taking yoga classes before discovering it’s still not possible) and lights where fitted being stupidly placed plastic housings that smash into a thousand sharp pieces as soon as the user misjudges the first doorway.
  3. Use of modern B2C sales and distribution methods – their products are offered on the Internet via their own website and online retailers such as Amazon then built to order and shipped direct from factory to customer. This not only cuts out the many layers of middlemen who each take a cut – which translates as “inflate the price”.

Finally – maybe the most important factor of all – the company lacks greed and uses a traditional cost-plus pricing model rather than the “hold the customer to ransom then grab all he cash we can get our hands on” model used by the big players in the market.

I don’t want to sing the praises of Wheelchair88 too highly or give the impression that they are a company who alone will take on the giants of the electric wheelchair world. I have explained that the company’s products have significant deficiencies but I will be forever grateful to them for coming up with the product that enabled me to once more drive a Maserati.

The important factor of note here is that try as they might to act like King Canute and suppress technological and commercial advances this small Malaysian company and the many others – both in Asia and around the world – are delivering similarly innovative designs that respond to real disabled people’s needs by making use of truly modern, 21st Century technologies and realistic pricing and in the process proving what has always been true – you cannot put a genie back in the bottle. Once new technology is developed and becomes commercially available people will find ways of using it to disrupt older industries or ways of working.

Using technology to enable – delivering business advantage to producer and consumer

These products are a good example of what I call “enabling technology”. They use newly available technologies (lightweight materials, modern design and construction methods, direct drive motors, energy dense lithium batteries ..) to deliver something that enables their customers to do things that were not possible before – climb stairs or throw the wheelchair into the back of a standard car – avoiding the need to install a heavy and expensive tail-lift into a large (and itself energy inefficient) vehicle.

But they remain only a harbinger of what I believe is possible with currently available technologies – it follows that more performant, enabling, practical products could be designed and delivered today without any crystal ball gazing or fantasies of technologies that may be “just over the horizon – honest!”

What should a 21st Century electric wheelchair be like?

OK – I have complained enough about the products and commercial behaviours of the existing big players in the electric wheelchair market and given a glimpse of what is possible using just a little 21st Century technology available today.

Time to put together my ideas for what a true 21st Century wheelchair could be like.

This is not a personal wish-list or a list of attributes that could be turned into more one-trick pony type products that appear and qiockly disappear as they fail to find a market.

Consider this list as a starting point – cast out to product designers, engineers and entrepreneurs wherever you are in the world. If you don’t already know that every item, feature or specification on the list is entirely possible with currently available technologies then look elsewhere for an interesting project.

The completion of this project is entirely within the scope of any university or college engineering department. It is most certainly capable of completion by any individual or group of competent engineers. Even one of the existing big players in the market could produce a product that meets all the criteria given – though I believe none have the bravery to up-turn their current business model to make the attempt – nevertheless they are welcome to try.

I see this specification as an open source project and freely give the ideas in the hope that individuals or teams will take up the challenge of turning the ideas into a product offered for sale on the open market.

If you are still reading, here goes:

Basic parameters:

  • the aim is to produce a lightweight, energy efficient electric wheelchair that embodies the best currently available technologies – this means that, for example, heavy materials like steel and old fashioned construction methods are to be avoided in favour of modern light materials such as aircraft grade aluminium, carbon fibre or non-loaded polycarbonate – similarly propulsion and control systems should display the best that modern technology can supply while remaining inside the envelope of safety, maximum reliability and ease of servicing at all times
  • the design should be modular, consisting of a base module (chassis) containing the batteries, electronics, wheels and motors on to which a range of seating, armrests and control mechanisms can be secured
  • seating options should be offered ranging from the lightweight “suspended net” type seat base and backrest to a seat that provides full tilt / lift / recline and standing (verticalisation) functions
  • in all possible configurations the wheelchair must be easily collapsible (eg; base frame and seating) with a single one-hand-operated control (ideally an electrical push-button with suitable safety interlock) so that its height once collapsed is no greater than 40~50cm so that it could be carried in the storage compartment of an unadapted car – the wheelchair should remain “drivable” (ie; capable of movement under its own power) to assist climbing of ramps to gain entry to a storage area
  • headrests (essential) should automatically retract into the backrest so that they do not protrude beyond the collapsed length of the wheelchair or exceed the maximum height allowed
  • the entire machine in all configurations should be capable of passing current and forecast crash test and safety requirements
  • the entire machine in all configurations should be capable of secure fixing to a car floor – for example through use of commonly available “pin & slot” locking mechanisms – for use by people who wish to drive from their wheelchair or those who must remain in the wheelchair while being a passenger

Business model

  • this is hopefully not an academic exercise
  • I hope that this long article poke somebody (hopefully a team of somebodies) into turning the ideas here into an actual product available on the open market at a price affordable to the greatest number of disabled people who might need it as possible – while still making profits for the company that achieves those goals
  • in order to achieve those goals the design, engineering, component selection, marketing and distribution functions all have to be considered from the outset and fit together with a common purpose aligned to the goals set out at the beginning
  • that effectively excludes any of the peddlers of 19th Century contraptions because their business model, operating and distribution practices carry such high costs that they stand no chance – unbless one of them suddenly decides to turn generations of cash-cow mentality into entrepreneurial spirit capable of taking on the young startups nipping at their heels
  • my advice is to look to the way that companies like Wheelchair88 succeed – by building a product that can be sold and shipped directly to a customer – then do it better – by building a better product that delivers better real world performance to a wider range of human beings

Energy supply

  • the wheelchair should be powered, if electrically, by (relatively) lightweight, high energy density batteries such as LiFePo4 types currently easily available
  • provision should be allowed for future energy types – eg; graphite based batteries or super-capacitors likely to appear during the life of a wheelchair purchased today – in essence, anything capable of supplying the requisite number of Volts and discharge current should be allowed to power the device
  • whatever energy supply is used it must be entirely safe and unlikely to catch fire or explode even after the harshest misadventure imaginable – as the occupant is by definition someone who cannot perform an emergency exit manoeuvre

Propulsion, steering and braking

  • the wheelchair should have four large (13″~14″) wheels, one placed at each corner of the chassis – allowing the wheelchair to mount real world kerbs and other obstacles
  • the wheelchair should have four-wheel drive – ie; every wheel should be driven
  • the wheelchair should have four-wheel steering (similar to many garden lawn tractors) providing a turning radius no greater than the wheelchair’s length
  • a steering mode should be provided that allows all four wheels to turn in the same direction – allowing the wheelchair to crab into confined spaces such as a wheelchair space provided on a bus or train or to access a table in a crowded restaurant
  • each wheel should be provided with independent, long travel suspension both to aid passenger comfort and deal with objects and pot-holes encountered
  • if electric propulsion is used then drive to the wheels should be provided by in-hub direct drive motors and steering by servo actuators – whatever motor type is chosen it should represent the best energy efficiency compatible with the anticipated control mechanism and feedback sensors envisaged – as an example only, the Axial Flux motor recently produced by Yasa Motors looks promising – see https://www.treehugger.com/cars/new-electric-motor-is-50-smaller-but-has-2x-more-torque.html
  • alternative propulsion mechanisms might usefully be considered – eg; hydraulic propulsion using a single electric motor to pressurise a high pressure hydraulic reservoir that feeds stored power to the wheels and steering system
  • braking, whether auto-activated by a “slow down” joy-stick command or urgent stop initiated by the user reversing the direction of travel should use the propulsion system in reversed mode
  • though a physical automatic parking brake should be fitted no other brake mechanism should be fitted (eg; mechanical discs and friction pads)
  • whenever possible braking should cause energy recovery

Seating

  • let’s just agree that the days of foam blocks and cushions held (huh! – you hope) in place by Velcro should have ended 50 years ago
  • while the most basic “strung net” type seating is suitable for some wheelchair users those who have reached my state of decrepitude need and deserve just a bit more …
  • imagine a seat – the one you sit in at work or the one in your car – now imagine being forced to sit in it for 15 hours a day, every day, every year for the rest of your life – and there are no adjustments … the manufacturer set it to fit you at an arbitrary moment in an arbitray day of your life and you get to live with it until the wheelchair or you die (whichever comes first) – not an appealing thought
  • just as we all change body shape over the years (an electric wheelchair should last 5~10 years remember) we also change shape or need to move around during the day
  • and from a business perspective how much more efficient is it to be able to B2C sell a product that’s about the right size and shape for a customer, safe in the knowledge that, just like a car seat, the seat can be adjusted by the user or his/her trusted professionals to best fit / maximum comfort
  • then, just as you would never survive a 15 hour car journey without shifting your weight and adjusting the seat a few times, we wheelchair users would appreciate the same functionality – redistribute your weight – tilt the seat and maybe adjust the backrest angle – more lateral upper body support – bring those side cushions in a touch – more or less pressure in the lower back – hit the lumbar support controls … back massage? YES PLEASE!
  • would I like to stand up? yes please! design and deliver a wheelchair whose seat not only tilts / lifts / reclines but also raises its occupant to a standing position – the importance of such a function to socialisation, normalisation and the maintenance of health cannot be over-stated

Control mechanism and functions

  • here lies a big opportunity to bring the electric wheelchair into the 21st Century
  • an example: record decks (anyone remember them) used servo-controlled electronics to monitor the precise speed of a rotating platten driven by a direct-drive motor that was part of the platten itself. A servo-loop is a fancy name for a feedback mechanism – something monitored the actual speed of rotation, something else compared that to a reference (the precise speed selected) and a large powerful motor was instantly adjusted to correct even the tiniest departures from the set speed – want to change from 33rpm to 45rpm (my age is showing)? simply flip a switch and the platten quickly and precisely changed to the new selected speed
  • imagine turning that mechanism on its side – and replacing the record platten with a wheelchair wheel – we now have a wheelchair that will maintain a given speed set by an external reference – what good is that, you ask?
  • existing electric wheelchair controls are essentially dumb analogue taps – they rely on the user to open and close the tap … “oh, the speed is falling because I’m going up a ramp, better push the joystick forward – yikes! I’m at the top of the ramp and accelerating way too fast towards a wall!”
  • what if the joystick stopped acting like a tap but instead allowed the user to set a speed and some digital electronics ensured that the wheelchair then proceeded to travel whether on the flat or climbing or descending a slope at a constant speed – the electronics opening and closing the tap as necessary?
  • why is this important? – because it opens the door to true 21st Century technology to appear
  • most people these days are at least familiar with such car conveniences as ABS braking, ESP (electronic anti-skid function) and automatic emergency braking – eg; if a forward looking sensor detects a likely impact it automatically applies the brakes far quicker than a human driver can react
  • by fitting simple sensors (stop thinking 1970s tech – modern direct motors already provide the speed data we want) an entire host of possibilities opens up – for example, I’m fed up of spinning my wheelchair’s wheels every time I cross wet grass – an ESP system would sense the sudden over-speed of the wheels and automatically throttle back the power to a point where it was within the level of grip available to the tyre – hence I would move at the maximum speed my wheelchair was capable of in the circumstances – similarly the most feared enemy of any electric wheelchair user … deep gravel … is almost impossible to cross because no matter how sensitive you are on the joystick “tap” at some point one or other driven wheel will lose traction, spin and dig itself into a hole before you can say “beached” – replace the tap with a digitally managed speed controller and the wheel-slip will be picked up and the power to that wheel reduced before the human driver even noticed it
  • take it further – 19th Century design wheelchairs turn by braking the inside wheel (that’s the one on the side you want to turn toward) – this is “safety first” but constantly annoying unless you are deliberately trying to race your wheelchair through a turn likely to tip it over
  • so, instead of braking the inner wheel, why not accelerate the outer wheel?
  • Safety, you say? so what if the wheelchair had an electronic gyroscope sensor (like the one fitted inside your mobile phone) … we now have a way of measuring the wheelchair’s angle of tilt which allows not only the automatic reduction of speed if the user attempts to turn at a speed likely to cause a tip but …
  • could be linked to that long-travel suspension – which if also dynamically controllable could act to tilt the seat within the chassis to either avoid an accident or allow faster cornering ( to anyone who thinks I’m looking to take up wheelchair racing, well you may be right – to a point – but the reason I am making such a thing about cornering speed is this … nothing makes you look more like a disabled drooling fool when, while walking along a city street with your wife at your side she suddenly turns to enter a shop where something has caught her eye … and you are left on the street trying to follow her – in a wheelchair that has suddenly developed all the performance of an arthritic snail – able bodied people can step sideways, turn and take off in a new direction without skipping a beat – I want a wheelchair that lets me emulate the same
  • and, if we have independent control of the power going to each wheel, sensors measuring wheel speed and a gyroscope measuring direction and tilt angle we can surely program something that loyally follows the direction the user points the joystick at – even if that means adjusting individual wheel power millisecond by milisecond while on the move – thus stopping my wheelchair from becoming an uncontrollable shopping cart heading toward the ditch and an inevitable painful crash every time I visit one of my favourite local restaurants …. which just happens to be at the end of a street whose camber greatly exceeds my 19th Century designed wheelchair’s ability to cope … it just gathers speed toward the ditch whether I lock the drive wheels or set them spinning in reverse
  • I could go on for days – but over to you folks – what could you do given a modern computer (something as simple and cheap as a Raspberry Pi will do) a bunch of sensors and a vehicle with dynamically controllable four-wheel propulsion, braking and suspension
  • when you run out of ideas on that level start to think of what truly useful (please!) user conveniences you could provide

And finally …

… that’s the tale of the current, appalling state of the electric wheelchair market, the bright future that faces someone brave enough to bite the bullet and bring a truly 21st Century chair to market at a reasonable price and the challenge to designers, engineers and entrepreneurs among you to build an electric chair using 21st Century technologies.

No prize but I’ll certainly be willing to try out any prototype that comes my way. Put something that meets the above specifications on the open market at a reasonable price (I deliberately avoided setting any price expectations but you can probably guess I’m not going to be impressed by anyone – college engineering team or existing big player in the market – that puts something like this on the market at a price point anywhere adjacent to 27,000 euros. Think carefully people and understand that much of the “ridiculously advanced and unaffordable” technologies described above are very likely in the car you use on the daily commute. Those components are made in such vast quantities already that they can be purchased retail for pennies.

Look hard – there’s nothing there that cannot be achieved today.

Though I have a good grasp of vehicular engineering through my life-long passion for exotic cars and how they work I make no claim to be a mechanical engineer. I am a solid IT techie though so if this turns into an open source hardware project then I can be counted on to provide some 21st Century collaboration mechanisms to help the process along.

As ever, I welcome your comments and discussion in the space below or elsewhere this post appears in the Fediverse so whether you want to fact-check me, you are an existing wheelchair manufacturer wishing to set me right on my thoughts about your products and business practices or an eager student, engineer or entrepreneur wanting to get involved I’m all ears.

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