Basic Wheelchair Maintenance and Repair


Welcome to the Utah Assistive Technology
Webinar Basic Wheelchair Maintenance and Repair. Our presenter today is Tom Boman, coordinator at the CReATE
program in Salt Lake City. CReATE and
UATP are both part of the Center for Persons with Disabilities
at Utah State University. If you have questions please click
on the Ask a Question button at the bottom of your screen. When this training is done,
please fill out an evaluation. The link is at the bottom of your screen. With that, we’ll turn it over to Tom.>>Morning everybody. I’m glad you’re with me. [LAUGH] Maybe not right here,
but glad you’re with me. This training will be pretty basic but
let’s just jump right into it. This is me. I’m CReATE program
coordinator as Julian said. I was formerly employed
as a safety engineer in manufacturing facilities in
different parts of the country. I studied public health,
industrial hygiene at USU and got minors in chemistry and Spanish. I’m a lifetime builder, tinkerer and
frugal fixer of broken things. I’m kind of a cheap-skate and it helps
definitely in the job that I’m into, to be a cheap-skate and
look for cheap solutions. And I’ve been in CReATE for about four
to half years as a technician and as a coordinator. So CReATE actually located
in Salt Lake City. What CReATE does is to accept donated
mobility equipment,we refurbish it and place it back out in the community. We serve all of Utah and we are part of
joint Utah Assistive Technology Program here at USU under the Center for
Persons with Disabilities. With the help of our volunteers, we placed about 20 mobility
devices with Utahns every month. We have no letter or medical necessity,
no medical justification or qualification process. People can simply contact
us at the number there or at the email and
then we can initiate services. Just what the stated need. And if you’re wondering what CReATE stands
for, [LAUGH] there’s no test on this. It’s citizens reutilizing
assistive technology equipment. So that’s the deep dark secret there, so. Our objectives today, we’re gonna be
doing basic training and information on maintenance and repair of wheelchairs and
scooters using pretty basic equipment. I’ve kind of geared this so that, say,
a new person, a new AT coordinator or whatever the position is called at
an independent living center that maybe doesn’t have much background in mobility
can basically get some basics and get on their feet with this. This is just an outline of what
we’ll be going over today. Basic tools in section 1, section 2, types of mobility equipment and
different seating systems, so that when I say something,
you know what I’m talking about. Section 3, we’re going over the basic
parts of power wheelchairs and scooters, which is critical in basically
doing some basic troubleshooting. Batteries are huge, so the section
4 batteries on how to charge them, test them, store them,
talk about capacity and voltage, we’ll spend a good amount of time on that. And the fifth and sixth sections
are gonna be a little less structured, but basically I’m gonna divide
it into my chair doesn’t work, my scooter doesn’t work,
it powers on but it doesn’t work or the joystick powers on and then doesn’t. Okay, we’ll go one and then the other. And then section 6, I’ll just go through some other general
hints with wheelchairs and scooters. Won’t talk a lot about manual chairs. Mainly it’ll be power but
we will mention manual chairs as well. All right, basic tools, this kit that’s shown here is, as it says on the slide, it’s probably 125 to $150. This type of work isn’t
as hard on tools as say, like my colleague Clay Christensen
here who used to work on diesels. We’re not putting that much
torque on the equipment so it’s okay to buy cheaper tools, basically. This kit,
probably somewhere between 125 and $150. That might sound daunting. But if you don’t have those on hand,
work your way through that. Metric and standard sockets, metric and
standard wrenches, basic stuff, pliers, screw drivers,
a simple multi meter like these. This costs about $18. This costs I think $12. Don’t be intimidated by these. I have never had an electronics class
in my life and I use these every day. You can learn these. I took physics but no real electronics. We’ll also talk about
a carbon pile battery tester. That’s probably a little less basic tool. But you’ve got to have the ability
to test batteries at some point. We go through, on the screen here, all these little zip ties,
I literally buy those by the hundreds. I suggest that, if you’re going to
be dong some basic work on chairs, you get some of those as well. What you don’t want are cables
on a wheelchair to stick out so that they snag on things. A cable that’s ripped out of a chair is,
yeah, sometimes hundreds to
thousands of dollars damage. So that’s really the important
of those zip ties. So if you have any questions about these
tools and as economical as they are and other recommendations for tools,
you could sure contact me. So this basic tool portion will be pretty,
well, it’s very basic, but I’m not gonna assume that people
have a background in mechanics. So I’ll just do some very basic things. You really want to avoid
stripped bolts and screws. And if you don’t know what that is, look
at the top picture on the slide, there. If you don’t use the correct screwdriver,
Allen wrench or hex wrench or box end wrench,
you could strip a screw or a fastener. Take the time to learn the tool for the job, tool for
the fastener you’re connecting it to. Take the time to use the right one. Because when you strip these,
it’s a big pain in the neck. You don’t wanna have to do that. Sometimes you simply inherit those
situations and you have to deal with them. But starting out from basics,
use the right tool. The screwdriver in the bottom
picture fits that screw very well. If you get one that’s too large or too
small, you could easily damage the screw and then it’s quite time consuming and
quite frustrating. I’ve used tools my whole life and I used to really pooh-pooh little
dividers and storage containers. I absolutely love them now. If you’ve an independent living center or some kind of care center have
very little to no space, I would highly recommend investing
in these little tool rolls or racks. Immediately if you look at
that wrench rack there, you know exactly what’s missing,
hey where’s my 13 millimeter wrench? It really helps. Not just because you want to make sure
somebody hasn’t walked off with your tools, but you want to make sure you
haven’t left it somewhere else, too. So they’re well worth the investment and
they can be very economical. Okay, Basic Tools, Current and Voltage. We’re gonna talk a little about voltage
and current, mostly voltage here. Okay and we’re gonna use, if I could
zoom in right here for a little bit. So do not be intimidated by volt meter. This is very inexpensive. We’re dealing with direct current,
battery power. So this is not really that dangerous. So it could,
if you’re looking at AC power and what comes out of the outlet it’s
definitely a different story. So okay, so this is a volt meter,
you can see the on and off button right here, okay? Oops, that’s the hold button. [LAUGH] There we go,
display right there, okay? So, typically, 98 plus percent of
the mobility devices use 24 volts, okay. So, when you use a volt meter,
you want to power it on, okay. And then,
you see the symbol on the slide there. I don’t know if we’ve
still got the slide up. Toggle back to that. There’s a symbol for DC and it’s a solid line with three dotted lines
underneath it, that’s direct current. That’s essentially battery power,
and there’s more to it than that, but that’s essentially what it is. So what you wanna do, you can see on this
volt meter right here, get my rights and my left screwed up on this display here. So you can see DC volts right there. So we want to test these two batteries
on the bench here for 24 volts. So what we have to set this voltage
range at is a value above 24 volts. So if you look at those values there,
we have to set this and we just turn this knob,
let me get my hand out of the way. We turn it to 200, all right? Don’t be intimidated by these. They’re cheap, I mean, yeah if you
damage one which is hard to do, it’s not a big deal, okay so
let’s see I’m going to try and get that display there so
I’m just going to show. Okay I’m going to do
something on purpose here. Okay I am showing,
get my this hand out of the way. I am showing negative volts,
is it possible to get negative volts? You just reverse your polarity
on your probes, okay. So red is typically positive,
black negative. You turn it on there and that’s reading with two of these
batteries connected 25.8 volts. So that’s to be expected. And that is most of the mobility devices. Okay, so here is your procedures, I kind
of jumped ahead on the volt meter usage. So turn your meter on,
move the selector knob to DC volts. Okay, I’m going to show a different
meter cuz that step three mentions an auto-ranging meter. And if we could zoom in just for
a split second on this meter, and there’s lots of different
meters out there. So, you notice that the volts
DC right there shows 1,000. Okay, that means this is auto-ranging. Anything below 1,000 volts it
automatically ranges appropriately. I’m not just to looking at the mirror
image of things, sorry about that. There we go. Okay, so then I wanted you to see
a different type of voltmeter and there’s a different one
displayed on the slide as well. So, don’t be intimidated by these. If you’ve never used one,
they’re very simple and we’ll show you two pretty critical
things you can do with that, okay. Place the red on red,
black on black, read the value. If you get a negative value,
you just reverse the probes. It doesn’t turn anything off. It doesn’t hurt anything, I should say. Make sure you turn your volt meters off. Most of them do not
turn off by themselves. It’s really frustrating
to pick up a volt meter, multimeter that has no battery in it,
okay. So one other thing with the multimeter or
volt meter, continuity. And I’ll talk a little bit
more about what continuity is. Well let me demonstrate it. Okay, continuity is kinda
just what it sounds like. Most people say when something electrical
isn’t broken, that it has a short. A short is when the positive and
negative touch and there’s sparks. When there’s a broken wire it’s called
an open, or an open connection, okay? So what continuity does,
it allows us to test for things that have a good connection,
okay, so. So I’ve switched this multimeter. If we could zoom in here,
I’ve switched this multimeter to the continuity symbol, okay? And you’ve got that on the slide as well. And you see that little horn symbol on it? That means you’re now set up to test for
continuity. And I don’t know if you’ll
pick up this little beep. But hopefully you can hear this,
I’ll lean in. Can you pick that beep sound up? [NOISE] What that means, these two probes, there’s a solid connection between these. So how you can use that on a wheelchair, let’s connect these two
red wires together. If we wanna connect, we wanna test,
excuse me, these wires, okay? Say these are on a wheelchair. We wanna know, hey, is the wire good? So what we could then
do is attach a probe. And it falls down. You attach a probe to each end of
this wire and you get the beep. Connect here. That means these wires are good. We’re getting a solid connection. Now, don’t know if you can hear that
little beep going on right there. But as soon as I disconnect this. Okay that means if this
were on a wheelchair and you didn’t get that beep that would be or it was intermittent, that means you
don’t have a good quality connection. So you’ve got the instructions
there on how to use a volt meter, a multimeter same thing,
to test for continuity. There’s another way to do this with
resistance, but this is simple. Listen for the beep, turn the volt
meter to the continuity setting, and listen for the beep. So pretty simple, try it, if you have
questions, get a hold of me, call me. So, all right, so this battery tester, this type of
test is called a carbon pile tester. It is probably the least basic tool
we have, a little bit more complex. If you have done any background
testing batteries in a car, these will be familiar to you. Ideally, if you’re working on a lot of
wheelchairs, you’re going to get a much more expensive tester that will
give you a different result. But I bought this, this is no plug for
Harbor Freight, but this was about $21. So not a huge investment and for the most part it will at least give you an
idea of the condition of a battery, okay? So when you go to test an individual
battery, keep in mind this is not something you can do while
the batteries are in the chair, okay? We’ll show some different ways
to look at charge in a chair. So you have to have the batteries
outside of the chair. If you bought batteries or
somebody donates batteries to your sensor, and you want to test them,
this would be what you would do. First of all,
you’re gonna want to charge them and then let them kind of rest from a half
an hour to an hour, so fully charge them. I charge them overnight,
let them rest, and then you’re able to charge
with a carbon-pile tester. I’m not gonna do it with these batteries,
these batteries are really small and these are really large clamps,
but I can demo it. Well maybe I should, because I’d like to
show you, get it on the edge of the table here and
have a little zooming action going on. If I can get these big clamps to
cooperate with the little batteries. Now these batteries are not fully charged. So I don’t expect,
are we getting this display right here? Okay, with this particular tester,
once you have the clamps set up on the terminals, what you do is
the instructions on this specific tester. Some of them say longer time,
some of them less time, but you’re supposed to hold this switch down. I’m gonna move that so
we don’t get glare on that. So what you’ll see, okay,
you hold this down for five seconds and that shows,
now this is a 12 volt battery, okay? This shows that it’s a bad
12 volt battery, okay? Just simply hold it down for that time,
and watch where that needle ends up. Now what you’ll expect to see,
these are pretty small batteries, not much current draw on them. There’s a heating element
within this that heats up, it puts a strain on the battery
to do this so it tests it. So it’s not surprising to me that these
batteries are bad, these are just for demo purposes. So this is an idea that you can use, and that’s a teeny bit warm there,
to test batteries. Batteries are pretty critical and we’ll
talk more about that in a little bit here. All right, mobility equipment, types of
mobility equipment in seating systems. Power wheelchairs are powered by two
rechargeable Lead-acid batteries and they’re operated through joystick. Power wheelchairs are not scooters,
there’s a big difference, we will talk about scooters
in a little while here. There are three main configurations of
power wheelchairs, front wheel drive. Notice the large wheels on the screen
there, the large wheels are on the front. Front wheel drive chairs tend
to be very maneuverable. There’s a slightly larger turning
radius than some other chairs. The controls are pretty intuitive. Notice there’s only four wheels. You’re seeing a side view, but there’s only four wheels on
the ground at any one given time. They’re decent for
clearing moderate obstacles. The first wheel that comes in contact with an obstacle on this chair
is the larger wheel. So it tends to be a little bit
better about clearing obstacles. And they usually has what
we call anti-tipper wheels, in this case they’re probably
hidden by the larger wheels. They’re just smaller wheels that stop the
chair from tipping all the way forward, and they typically don’t touch
the ground if the chair’s well adjusted. Mid wheel drive chairs,
the larger wheel is the drive wheel, and that’s in the center of the chair. These are also very
highly maneuverable and it essentially turns within its own space. It can essentially turn 360 until,
[LAUGH] until the batteries wear out and really not go any farther forward or
backwards. They don’t clear moderate obstacles
as well, or soft dirt or gravel, because the first wheel that comes in
contact with things are those small caster wheels in the front. So they tend to get bogged down in
soft dirt and gravel and stuff. But they are very stable, but those front caster wheel take every little bump,
and they can wear out pretty quickly. Last configuration is a rear wheel drive, on this chair the large
drive wheels on the back. It’s got a very large turning radius. So wheelchairs turn not by
using a steering wheel or a tiller like a scooter does. But almost like a tank does where
one wheel pushes the other, one pushes for, one pushes back. So you can imagine in a rear wheel chair, the whole chair pivots in
front of the drive wheels. So the turning radius if you will, the radius of that circle is almost twice
what it is for a mid wheel drive chair. They are great for outdoors,
not so good for indoors, simply because they don’t
navigate smaller spaces well. But they’re great for outdoors. They used to be a lot more common, we
don’t really see too many of them around. They also do have like you can see on
the back like the front wheel did, anti-tipper wheels. That shouldn’t be touching the ground if
the chair is properly adjusted, okay. So quickly go through
rehab seating systems, so there’s different we call
them seating systems. And it took me a few months before I
really got these terms straightened out in my head. Rehab seating systems are they
can have power functions or not, but they’re mostly black. Most people that, even if they’re
not familiar with wheelchairs, they’ve seen a wheelchair that may be
complex, and the seat cushions are black. And the back and
the seat frame itself are black. Those are typically rehab that’s
typically rehab seating systems. Rehab seating systems are meant
to be highly customizable. You can replace the seat back and
the seat cushions with gosh dozens of different options that
would meet specific needs for people. And there are a lot of custom supports for
hips, legs, calves, even for heads and
hands, troughs for arms. It’s pretty amazing
the different needs that you can accommodate with a rehab seating system. The seat size, the cushions,
the power functions, all of that is tailored for
each specific user. So it’s actually kind of gratifying to
work with this to meet specific needs, especially when someone is not well fit in
the current wheelchair that they’re using. So I mentioned, in the previous
slide I mentioned that rehab seating can be powered or non-powered. Which means that elements of
the seat can move electrically, it’s not hydraulic,
it’s all electric, okay? So in the power rehab seating
systems the function of tilt is when it’s like
the bottom picture below. When the back and
the seat move at once that’s tilt. Recline in the way we use it
is when the back only moves. Power elevating leg rest is exactly what
they sound, either individual legs can raise, or raise legs lifts together
depending on the specific chair. And there are chairs that
have power elevate as well, the middle chair in the top photo there
is showing a power elevate function. And then on the left hand side on the,
excuse me on the right hand side on the top photo there, is actually a
power standing chair which are very rare. But yeah we have had a few of those,
about a half dozen of those at CReATE. And you can actually stand
someone up vertically, and they can drive around, pretty cool. So any combination of these
functions can be present in a power rehab seating system, okay? Or there can still be a rehab seat
with no power functions at all. Okay, The other general type of seating
system is what we call a captain’s or van seat. It’s more general purpose wheelchair
seating, there’s varying colors. Typically, for users that are less
impaired, maybe spend a few hours in a chair each day, situations vary greatly,
but they’re more generic in purpose. They can’t be customized nearly
as well as much as rehab seating. So we’ve got rehab sitting and
captains or van seating, okay? We’ll talk a little bit about manual
wheelchairs, there are three main types. Rigid frames are the lightest, their the most durable, the best quality
components, they’re the most expensive. A lot of the frames are made out of
titanium and aluminum, which is a big problem when we go to repair them,
because it’s highly specialized welding. The frame itself in a rigid
chair does not fold up sideways like a lightweight folding does. The wheels are typically removable and
the back will fold forward. So if you can look at that image there,
imagine it without the main wheels, the large wheels, and
then the back folded flat. Still is pretty compact if it has
to fit in a back seat or something, but not quite as compact as this
next type, lightweight folding. I should mention on
the rigid frame wheelchairs, manual chairs they’re by far the most
expensive, and typically those people that are in a manual wheelchair most of
the day are using rigid frame chairs. Lightweight folding collapses side to
side, you see the bottom photo there, versus the top,
the wheelchair collapses in and of itself. Usually slightly heavier
than the rigid frames. Definitely better quality components in
the lightweight folding and the rigid chair, when you compare them to the black
and chrome standard hospital chairs. Both of these types also use rehab
seating that we just talked about. Meaning that you can change the higher
the seat back, the different cushions at different lateral supports and
a host of different things. These are very versatile, general purpose
chairs, and I’m sure you’ve all seen these, even if you’ve got next to
zero experience with a wheelchair. We call these standard wheelchairs or
hospital wheelchairs. Lower end components, definitely heavier,
not intended to be used for many hours during the day,
although we do see that. You typically not used
with other cushions but you can obviously throw a cushion
on there if you need to. Not very customizable and
they’re less expensive. Transport wheelchairs are very
similar to the hospital chairs. They’re just typically meant to
get a person from, lets say, a car to a doctors appointment. You can’t really self propel in these,
so someone really, typically, has to be pushing, unless someone
can propel with their feet, and their pretty light, pretty inexpensive. There’s also tilt in space manual
wheel chairs, definitely heavier. I don’t envy the people who have to,
Moms that have to lift these in and out of a car for their little kids, typically
don’t accommodate self-propelling. So notice the large drive wheels aren’t
very large compared to other manual chairs which being someone’s pushing the chair,
some do but most don’t. Essentially, this is the only
tilting manual chair okay? Typically used by a users by
greater level of impairment. And these seats are rehab seats,
which means there highly customizable and really unique for each user. Okay, so I mentioned we were
going to talk about scooters. These are scooters those photos you see,
they’re not power wheelchairs, very different. Three and four wheel versions
of scooters are available. As you can probably guess,
if you don’t know already, the three wheel scooters are more
maneuverable, but they’re less stable. The 4-wheel scooters are definitely more
stable, but they’re less maneuverable. You take a scooter like that
4-wheel one and try and turn it around in a slender hallway, it’s
going to be a 8 to 12 point turn [LAUGH]. So where is mid-wheel drive chair,
it’s just going to flip, simply and do an 180 and turn around. So again it’s best for outdoor use,
not a good choice for indoors unless there’s really large hallways and
easy access through doorways and what not. For some reason, manufacturers don’t put
very large batteries in scooters either, so they tend to have a much shorter range. In terms of batteries, the larger the battery essentially
means a bigger gas tank. There’s more to it than that, but essentially that’s
the case with batteries. So scooters also tend to have a much
shorter range than power wheel chairs do. Okay, no questions coming through. Yeah it’s pretty basic stuff here so, now we’ll start getting into the stuff
that may be less common knowledge, so. All right, so power wheelchair components. Power wheelchairs are driven, controlled
by joysticks, they’re not controllers, they’re joysticks. Each wheelchair has its
own unique joystick. And we’ll mention other components, but
one specific joystick has a specific set of electronics that it
must be connected to. So you can’t take one joystick
that’s not like another one and just swap them between chairs. Power wheelchair joysticks have
what’s called proportional control. So as you move the joystick
forward a little bit, the chair only accelerates a little. As you move it all the way,
it moves within the speed, giving the full extent of what the speed
is allowed as it’s programmed. So the more you move it,
the more the chair moves. It requires very little pressure. We see a lot of new wheelchair users,
so to speak get in a wheelchair and just slam the joystick forward. I typically do a lot of test
driving of wheelchairs, I typically drive with my thumb. Very little pressure, probably less than
two or three pounds of pressure, required. There’s a lot of different types of
joysticks, we won’t go into that. That’s too detailed for what for
what we need to talk about today. But there’s at least eight common
types of wheelchair joysticks. Wheelchair the joysticks get blamed a lot,
they’re a common scapegoat. The joystick is what people interact
with the most with their wheelchair. My joystick doesn’t work,
I hear that a lot. And then we’re going, okay, there’s a lot
of reasons why a joystick couldn’t work. It’s not necessarily the joystick in and
of itself, and we’ll go through some of those things. Okay, so wheelchair motors, switching
gears here a little bit, no pun intended. [LAUGH] Okay, so this is a very common power chair
motor right here in front of you. What you have got on your well
that would be your left side, the silver portion there is the gear box. The black body there the round
body is the motor, okay? The free wheel lever there, a lot of people would look familiar
with power chairs even a little bit. Understand that when a chair breaks
you have to put it in free will. What that lever, what that lever will do
if you turn it will disengage the gears within the gear box and
allow the drive wheels to move freely. So if the chair fails or
whatever weird situation happens, you can actually physically
push the power chair. Some other wheelchair motors don’t
have the lever on the gear box. They have,I don’t know if you
can see this cursor here, they have a brake disengage
lever back here, okay. So, there’s a drive shaft, typically
connects to the drive wheel, the motor. The brake is usually on
the very end of these motors; always on the end of the motors. For that matter, for those of you that
are especially really new to wheelchairs, the clicking sound you hear is the brake
engaging and disengaging in a power chair. And I am going to try and
just demo that if I can right over here. Okay, so the brakes on a power
wheelchair are essentially always on unless you disengage them,
but we’re not gonna go there yet. So you’ll hear a click. When I move the joystick,
the chair barely moving, when I let go, there’s another click. So the brakes are in
engineering terms failsafe. If someone passes out and
let’s go of the joystick it should fail, it should return to center and
the brakes engage, okay. You’d be surprised at some panic
new users that we fit in chairs and they’re like where are the brakes. But anyway, brushes are pretty
critical with motors as well. The little arrow there
pointing to the little round, there’s a ca little plastic
cap that holds a brush. There’s always an even number of
brushes in a motor, either two or four. If you’re familiar with wheel chairs,
you may have heard of two-pole, or four-pole motors, that refers to
the number of brushes on the motor. The brushes basically deliver the power to
the motor, so the more brushes there are, essentially the more power
the wheelchair motor can have. So all these different elements
are potential points of failure, which is why we’re going
through them right now. Scooter motors are a little different. With wheelchairs, there are always two motors with
scooters there’s only one motor. So, the motor looks quite
very much the same. You see a brake lever that
you can engage and disengage. There’s brushes in these motors as well. The drive shaft goes all
the way across the scooter and there’s a wheel on either end. And, if you’re familiar with what
a differential is in a truck or a larger vehicle, it enables one wheel to
move at a different rotational speed than the other is what scooters have
because they need to turn corners and one wheel needs to move
at a different RPM. But, yeah, so only one motor per scooter,
two motors per power chairs, okay? So this, right here. When I saw this, or a similar diagram for
the first time, I’m like, wow, okay. That’s cool, because these are the basic elements of
a power wheelchair right there, okay. So in the center of that, you see what
looks like a little computer, and it’s called a power module. Sometimes, it’s called a controller, okay. So in essence you’ve got two batteries,
we talked about 24-volt batteries, two 12-volt batteries which makes 24-volts,
that feeds into the power module, okay. The power module is the central computer,
if you will and the joystick gives input to that computer, to that power module and
it sends power out to either motor. Now, if you’re turning,
say you’re turning right, okay, and wanna just turn 180 degrees, turn yourself
around, you turn right, what it will do is it will tell the left motor to go forward
and the right motor to go backwards, okay. So all that is controlled when you
move the joystick to the right, the computer translates that into
signals for the wheel for the motors and tells motors to do,
two motors to do opposite thing, okay. Now, why is it important to understand
this, when you’re looking for potential points of failure you need to
basically have this diagram in your head, okay, this is a basic power chair. And there’s a lot of power chairs
that also have power seating. But in essence it’s the same thing, but there’s another little module
advanced seating module or advanced actuator module,
that’s just another smaller computer. Typically on the back, let’s see,
I think there’s a cover off of the back of this and I can show you
what these modules look like right here. This is that secondary
modules right there, okay? So you’ll see a lot of different
connectors and it looks like a rat’s nest of wires, in essence, this is what even a
more complex chair is at its heart, okay. So again, when you become more familiar
with these in essence that’s what you’re dealing with either the simple diagram
before this one here, or this one. So it was really helpful to me as I was
learning this to have that in my head. So, okay,
scooters very similar you have a module, a controlled module that
regulates the power from the and in scooters the control is not a joystick,
it’s called a tiller. You have a lever to move forwards and
backwards but very similar diagram there, okay. All right, terminology,
the large wheels are drive wheels. The smaller wheels are caster wheels. Caster wheels typically not only roll but
they also swivel 360 degrees, okay. A lot of people are wondering what
these little tiny wheels are in front. A lot of new,
people that are new to wheelchairs wonder, well, those wheels aren’t on the ground
and the small ones in the front. Those are a safety feature, stabilizer, anti-tip wheels to keep chairs
from tipping over, okay. All right, batteries are pretty big in
terms of what we deal with in wheelchairs. Battery types,
these are all wheelchair batteries are valve regulated lead acid batteries or
BRLAs, okay [LAUGH]. If you use the approved batteries,
they’re sealed and they’re safe for public transportation and
there’s two general types, AGMs or Gels. As we’ve mentioned several times now,
there’s always two batteries, okay, in mobility devices,
there’s very few exceptions and they’re such outliers that we
won’t even really talk about them. They’re lead acid batteries, most cars
have lead acid batteries as well. These are slightly different
type [COUGH] excuse me, because they are sealed and
you don’t need to add water to them. I need to add water to me. Ni-Cd, lithium and other battery types are typically not
in use in mainstream mobility devices. There are mobility devices that are kind
of more outliers that use lithium packs and everything, but the main devices
that are covered by insurance and they’re dealt with by professionals don’t
have Ni-Cd batteries or lithium batteries. Okay, we beat this to death a little bit,
but two 12 volt batteries are required for mobility equipment. And if one goes bad you
gotta replace them both. I use the analogy of somebody in
the old West driving a wagon and one horse is good and one’s bad. Basically eventually they both become
even the good horse gets worn out. So you can’t replace one battery and
not the next, okay? I was hoping to have
a battery to show you, but there are actually cells within a battery. So a 12 volt battery has six divisions
in it, each one with two volts, okay? So when a battery truly fails, one cause of failure is
what we call a bad cell. So if a battery measures
about 12 volts and one of those six cells goes bad,
when it’s fully charged it will only get, even if the rest of the cells are good
it will only get up to about 10 volts. Another big cause of battery
failure is basically, I call them, starved batteries, okay? It’s basically due to a lack of charging
or a number of issues, bad charger, infrequent charging, or somebody leaves
and leaves their chair for a month and comes back and, or poor connections. Remember the diagrams that we saw? Any of those connectors that lead
to the batteries if those are bad, then basically the battery
doesn’t get fully charged, and it can basically starve the battery and
it will lose capacity. The two main types that I
mentioned before are gels and AGM, they’re both lead acid batteries, okay? The acid is sealed in these batteries so
if you drop the battery, the chair falls, or
it’s in public transit and, heaven forbid, falls off a lift or something,
the idea is that the acid won’t leak out. The same for airplanes,
if there’s a bad landing or something, they don’t want acid
leaking for obvious reasons. AGM batteries are Absorbed Glass Mat. I had the manufacturer describe it to me
as basically kind of like a fiber glass sponge that holds the acid in, okay? Gel batteries, instead of having
the sponge to basically have a gel, that is the acid, okay? Gels are more expensive than AGMs,
the gels have far more charge cycles. Now this next slide kind of rock
my world when I first saw it. So if you and your censor or
shopper, wherever the case maybe, are looking at gel batteries
versus AGM batteries, you really need to understand this graph. So what you see in the left column
there is depth of discharge, it’s not Department of Defence [LAUGH]. Depth of discharge, so the amount of
battery from 100% that it’s discharged, so 100% depth of discharge is 0 charge. 80% discharge, it’s only got 20%
of the charge left, and so on. So 10% depth of discharge,
it’s still got 90% of its discharge. So these are charge cycles,
so that’s essentially, if you charge once a day,
how many days you can re-charge a chair. So let’s take the 50% depth of discharge, which means you’ve got half of your
charge left at the end of the day. And with a gel battery,
you have 1,000 charge cycles. So almost three years use of charge
cycles on a gel battery, okay? With an AGM, you have half that, okay? And you can look up and down that
graph to realize not only the fact that gel batteries last a whole
lot longer than AGM batteries, but what the depth of this charge does for
the life of your battery. So and I know people who believe in this, they have to discharge their batteries
down to 80% and then charge them. They’re gonna charge them too much and
wear them out, that’s bull, that’s bupkus. Because if you look at the 80% discharge,
okay, let’s just look at the gel, okay? If you discharge 80%, you limit your
charging cycles to 600 charge cycles,okay? As opposed to 50, or 25% discharge, okay? So the long and short of it,
gels are far better than AGM batteries, and charging you can charge if you only
use 5 to 10% of the charge in your chair. You can charge, theoretically for
five to six years, the batteries will last you, okay? So what that translates into is, you can charge every night,
there is no problem with that. Batteries down to third point on this functional modern wheel chair chargers
cannot overcharge batteries, okay? For RESNA/ANSI standards, the chargers turn themselves off after
they fully charge the wheelchair. And when the chair if it’s left, say for a week or more, the charge drops and
the chair of the charger kicks back on, tops the charge off and
turns itself off, okay? Older chargers that
are 20 plus years older, may not be this quote unquote smart, okay? But modern functional wheelchair chargers
cannot overcharge batteries, okay? So other myths,
if you have a separate battery and you put it on the ground,
it will not discharge, okay? That’s kind of an urban legend,
apparently they used to make the cells in the batteries out of glass and
have kind of porous cases for the cells. So the glass won’t crack cuz
there is no glass in these, okay? So it makes no difference whether
you put them on the ground or not. Lead acid batteries do not
have memory issues, okay? NiCad batteries that were
very prevalent 10,15, 20 years ago, if you only used 10% of
them and charged them their capacity, their ability to hold a charge
would diminish greatly, okay? Lead acid batteries are not NiCads,
they’re not lithiums, they don’t have the memory,
quote on quote, issues, okay? What you can do,
with a lead acid battery is starve it. As we mention before, if you don’t charge it up fully that you
will definitely reduce the capacity. So but that’s not what we
consider a memory issue, okay? Again, as a myth there, I’ve listed
my batteries will last longer if I only charge them once a week,
that’s not true, okay? And at 10, 15, 20%, depth of discharge, you can almost recharge
the batteries indefinitely. And it doesn’t make any difference
in terms of the longevity, essentially of your batteries, okay? Just because the last myth there, just
because your joystick says you have a full battery charge doesn’t mean that
your batteries are good, okay? We’ll go into this,
that’s a good segue way into this, which is charge versus capacity. Why is it always the guys that come, the
husbands of the clients that we have, they come in they’re like well, why won’t these
wheelchair batteries last five years, my truck batteries last 10 years. Batteries in wheelchairs
are the sole energy source, okay? There’s no gas engine,
I know of no commonly available hybrid wheelchair that runs on gas and
electricity, okay? So remember, batteries are the only
energy source for a powered wheelchair. These wheelchair batteries need to be
marathon runners, not sprinters, okay? So car batteries give a big jolt of
electricity that call cranky amps, they start the engine, and
then they kinda sit in the background. Wheelchair batteries
need to last a long time, a slow constant discharge of its current. And so they’re different animals,
so to speak. In terms of battery charge, a standard
voltage for a wheelchair battery ranges, and this is an individual battery,
keep in mind, from 12.7 it’s fully charged, 11.7 is no charge. That’s not very intuitive, but
that’s technically what the range is. You can actually see a little
bit higher charge than that on a battery right when you
pull it off of a charger. If you’re gonna test, as I mentioned
earlier with testing batteries, you’re gonna wanna let the battery sit for
a while after you charge it and then test it to get
an accurate reading off of it. Okay, so
I wanna do a little bit of a demo here. I showed you how to test battery voltage right on the battery. You can also test
the voltage on wheelchair whether it is on or
off without even looking at the screen. So, let’s see, I’m gonna turn
this a little bit to the side. Well, no, that’s not gonna work either. We don’t need to see the display screen,
what I needed to see is this port on the bottom side, right here, right there. Guess I need another tester. [LAUGH] Okay, so I’ve got my range
set to 200 volts DC because, remember, I know we beat this to death
that there’s 24 volts in a wheelchair. So these two holes right there,
we got negative volts. My polarity is reversed, big deal. So what does that tell me? That tells me, hey I got batteries
connected to the power of chair, and there is electricity all
the way up to the joystick, okay? If the joystick does not power on,
but I’ve still got power here, that means there may indeed be
an issue with the joystick, okay? So again,
this connector’s called an XLR connector. It’s old microphone type connector. I can show you the other end of it, if
you’re familiar with wheel chair chargers, this is the opposite end of that, okay? So what you’re doing is
testing two of those holes. And don’t worry, you can’t put these
in the wrong holes on here and pull the chair out or shock yourself or
anything like that, okay? So if you don’t get current across these, your voltage across these, that would
tell you there’s either bad batteries or bad connections somewhere
within the chair, okay? All right, so charge can be checked on
the joystick display if it’s working. But you can also check it in what
we call that charging port or the programming port too. Okay, mobility batteries, AGM and Gel batteries, most of them are approved
for public transit and air travel. I get frantic calls from the airport,
somebody saying, I’m at United and they won’t let me get on the plane,
are these batteries approved? We only use this brand of
batteries that are Gel and there’s a statement right on the battery,
DOT, FAA, and IATA. Those requirements are met, but
I would look, if there’s any question, look right on the battery itself. If the battery itself doesn’t have it, I would go to the manufacturer
to get certifications. Keep in mind that manufacturers have numbers of different
batteries that they offer. And you’re gonna be,
need to be very specific, or they’re not real probably gonna give
you useful information there, okay? So, we’re gonna kinda switch gears
a little bit and we’re going to, let’s see and a back up here. And how much time do we have? Like five minutes? Ten minutes?>>[INAUDIBLE]
>>Okay, all right.>>[INAUDIBLE]
>>Okay, all right, well I better go. Joystick out of center, okay, be nice. Sure, now this chair is. Okay, now it’s, this is pushed forward,
that’s why, okay. All right, so we’re going to take basically a case and
I think we said, what? Joystick does not power on, or joystick
does power on, but the chair won’t move. So if that’s the situation in
an independent living centre, you get a wheelchair donated,
the chair turns on, but it won’t move. The biggest thing, and some of you
will laugh, but the biggest problem is typically the fact that
the it’s in free wheel mode. Some chairs when the chair is in
free wheel, won’t move at all, okay? But in this case,
we can have this chair in free wheel, so notice I can push the chair, the chair
will drive on one side, not the other. [LAUGH] So, make sure it’s in free wheel. Okay, I know that’s painfully obvious. The chair being on and not working, make sure that
the control buttons are responsive. See I can’t quite move this to show
the knobs, but there’s a speed knob and a lot of them more complex. Step through the different profiles
an power functions on the chair, test all the different ones,
make sure that’s working. If the joystick powers on and the chair
doesn’t move, and there’s a problem, you’ll typically see,
either on an LCD screen, an error code. Those numbers that you will see on those
error codes, they’re very critical. We can go back and reference technical documents to
show what that specific error is. And usually it’s quite helpful at
letting us know what the problem is. If you don’t have the LCD screens,
you just have the lighted screens, look at either the number
of flashing lights. Typically there’s ten lights, and those
lights will flash a given number of times. Typically anywhere from one
flash to twelve flashes or, sometimes It’s the number
of flashing lights or the number of times the lights flash,
if that makes sense. So, there are two different ways, but
it will give you typically a number, again, from 1 to 12 and
those numbers mean specific things. Another critical thing, if the power is on
on a wheelchair and the chair won’t drive, and, I’m going to need to somehow,
can you tilt that down to see this screen? Right where my finger’s pointing, right? Can you get down? Maybe I should back up a little bit more. Okay, maybe we’ll navigate
this just a little more. Okay, now I’ve just bumped this
attendant control on the back, and this main joystick didn’t like it. So, we showed you the module
on the back of the chair and that controls the power seat. There’s an angle sensor in that and
there are threshold angles that essentially either slow
the chair down or lock the chair out. In this case you can’t see
it very well here, but there’s essentially a stoplight there,
with red, yellow and green lights. As you tilt this chair back, and
you won’t be able to see this, that is, you tilt,
in this case reclining the chair back. Immediately, that light
went from green to red, which means now if I put it back
in drive mode, the chair is on. The wheels, it’s not in free wheel,
I can’t push the chair, but the chair won’t drive, okay? Again, power is on, chair won’t drive,
check the other things we mentioned, and also, if it’s got power seating, return
it to what we call the home position. Straighten the chair back,
retract the legs, and see if you can get the chair
to operate that way. We’re gonna move that forward and
that should clear. Yeah, okay, so that went green, and
now the chair will drive, okay? So, those are basic things to
check if a chair won’t drive. Now, about three years ago,
I got a frantic call from a PT, a physical therapist In a school someone in Central Utah that said that the chairs
that she just bought rom us don’t work. There is one other reason why
your chair would power on but not move, and
that is if the charger is connected. So this chair drives right now But
notice when I plug the charger in. As a safety feature the chair won’t drive. This is precisely so that we don’t rip
these cords out of the joystick and then out of the wall as the chargers
plugged into the chair. Okay, so in that sense that’s
Chair powers on but won’t drive. There’s a lot more that we could go on but
those are some basic tips to how to deal with a chair that
powers on but will not drive, okay. Now, a chair that will not power on and
will not drive is as you can probably imagine A whole lot less facts and a whole lot more
that can be wrong with them, okay. One of the first things to
do is to check the voltage like we showed you across
these connectors here. So we already know that this
This is about 25 volts. Okay.
And, if you remember, 12.7 volts is a full charge
on a 12 volt battery. So, multiply that by two, okay. 25 volts, my polarity’s reversed here. So, 25 volts is enough
charge to move a chair. Okay? So, if this did not move, or did not turn on, At least we would know
that there’s voltage to the joystick. Okay? I’ll just do this kinda right here so
we don’t have to change the camera angle. So this is a simpler joystick. Okay, so what I’m gonna illustrate
here is the importance of connections. We talked about continuity, okay? So a lot of you’ve dealt
with wheelchairs before. You’re probably familiar with
this type of joystick, okay? This is not connected to a chair, so there’s no No surprise that
this will not turn on, okay? This joystick, in particular, is really
famous for this switch being stubborn. [LAUGH] People beat on it and
beat on it and it’ll finally come on. So what the issue is a lot of the times,
and this is not glued on,
I intentionally left that loose. What you see is this
little black knob here. That’s actually conductive. So that means if we put the connectivity
testers on either side of this, it would beep. Okay. So it’s essentially like copper. That little black thing. So what that has to do is
go down in this hole and there’s interlacing Pattern there and
that has to make contact, okay. If this little- if these tips are dirty, or there’s dirt and grime down in there,
it’s a poor connection. And what that ends up being for
the users is, they’re beating the fool out of their Of their,
a power button and it finally comes on. So we see this an awful lot. My joysticks bad,
I want to buy a joystick, there $500 new. A lot of times you can simply, if you’re
daring enough to do this, you can definitely try this yourself but you can
take a pick A sharp pick can dig this out. They’re typically glued on. Most of the time it’s with
a very thin double-sided tape. And I use denatured alcohol to clean. But you clean all the excess
adhesive out of here. You can actually put denatured
alcohol down inside here. It evaporates very quickly,
it’s non-conductive I use Q-tips to clean. This is actually a circuitboard underneath
the CEC there, those copper leads there. It’s a printed pattern on a circuitboard. Okay, so clean those really well. I stick some compressed air in there and
try and blow some of the excess alcohol out of
there, remove all of the adhesive residue. Get it super clean. And then I also clean the back of this,
okay. These little, if these little black
dots if you will have worn out, you’re not going to be able
to clean this and replace it. You’re going to have to buy
a replacement version of these. This, my wholesale cost through
my supplier, is $45 for this little piece of rubber. Okay, you can sometimes find these for
a specific joystick on eBay and stuff like that. That would be cheaper than buying
a new joystick But anyway, so if this button is broken,
or those little conductive tips on that are broken,
then you’re not gonna be able to do this. But anyway, so clean this thoroughly,
even down inside there. Blow out the excess alcohol,
clean this, then reglue it on. Now you will only want to apply glue. Where these buttons are not. [LAUGH] Okay so if you put you
can see how that compresses. Okay if you put glue
on the bottom of that, when you push it down it
won’t ever come up okay? So this is the $10 fix to
a $500 problem right here. I typically use automotive
trim glue On this, there is no wheelchair joystick glue. I use quite a few different
automotive type glues. I can show you. I actually brought the glue with me. This is the This is the brand that
I’ve used, there’s plenty of other, you know I’m not making a pitch for but
I really do like glue for this very thing. This glue also is very good
at gluing joystick knobs on. I got very tired when I first
started doing this job at. Glowing joystick knobs back on. [LAUGH] So I’ll actually put a little
bit excess glue on the joystick knob and thoroughly clean this post and
the knob itself and apply enough glue to where the joystick
sticks to this little shaft. And also glues this boot
to the knob itself. So, and
that tends to help with that, okay? .
So again, keep this in mind if you’ve
got questions on how to do it. It’s really not hard. If the buttons themselves,
if the rubber hasn’t been overly worn out, you can do this. You can do this on a number
of the simple joysticks. Even the more complex joysticks like
this one has, this other joystick has, still has a small rubber overlay or template, whatever you want to call it
that is essentially this same thing. It’s a little thinner,
different button configuration, but it’s got the same thing where
a small rubber knob if you will, pushes down with the conductive surface
and makes contact on a circuit board. So, yeah, in fact, a lady came in last
Thursday, panicked, needed a new joystick. And this took us about, I mean
obviously we’ve done this a lot, but it took about five minutes and
it powered on immediately. And you didn’t have to beat the fool out
of the power button to get it to turn on. Okay, continuing on with the joystick
does not turn on and the chair won’t run, obviously if the joystick’s not
turning on the chair won’t run but not everything is obvious. Okay, so what you’ll want to do,
is check connections. This is not the necessarily the best chair
to demo, but we’ll try and show you. So in essence, with a lot of this,
you follow wires, okay? Dean, hold that right there for a second. Some joysticks have a connector,
a removable connector right here. I don’t like those because it
is a very easy point of failure. But if there is a connector there, take
that off and check the condition of it. If it’s grimy, you can take a simple toothbrush with some
denatured alcohol and clean that off. Denatured alcohol is really cheap. And it’s a cheap solvent,
readily available. And it’s inert. It won’t hurt. It’s not conductive. So you can easily use that to clean those
connections, [SOUND] and put that back in. So, you can clean connector,
potentially, you could clean one there. You could follow the wire back in
the back see where it connects, okay? A lot of times we see
just a simple connection. A bad quality connection
is the cause of failure. We love it because when there’s
a simple fix like that. So, in essence, follow connectors. A lot of these are outside, at least some
of the basic ones are outside the chair. So, eliminate the low-hanging fruit first, to check why the power
chair won’t turn on. If you’ve got good voltage, and this won’t turn on, resolve
the button issue, check the connectors. If at that point it’s
still not turning on, then you may have an issue
with a power module. You may have an issue with a joystick. It gets a little more complex after that,
so. I think that’s pretty much it in terms of,
well, there’s one other thing
I wanted to mention. And I should’ve mentioned this when
I talked about when the power chairs power on, but do not work well. I’m not belittling a certain
brand over another. But, certain brands of wheelchairs and
their electronic sets, if the batteries are failing,
they do not, it causes a host of electronic issues and causes
you to essentially, chase your tail. And it will throw a lot
of different codes. So if you’re trying to fix a chair and
you can’t find what’s wrong with it, make sure that you know
you’ve got good batteries. And you can power that
externally if you need to. But make sure the batteries are good when you really start delving
into the repair of a wheelchair. I wasted several hours about six weeks
ago thinking the batteries were good and they weren’t. And when I replaced the batteries, about eight different errors
completely disappeared. So anyway, make sure that the batteries
are good, before you start to quote unquote, chasing your tail
with these different errors, too. So, start simple. There’s a lot that you can learn from
just eliminating these simple things. So. All right, there’s a different
chair right here [SOUND]. One of the tips that we’re pretty proud
of and we’re happy to figure out, this a Jazzy chair. The Jazzy chair has this,
it’s a soft pad here and this plastic trough, black plastic trough. 90% of the donations that come
in have door paint right here because they slam into the door and
scrape. The best thing to get that paint of,
is just a simple solvent like mineral spirits or something like that,
and some steel wool. You get a little bit of abrasion, but the mineral spirits give it a little bit
of lubrication and it takes the paint off. And really doesn’t do
anything to the plastic. And part of what we do in providing mobility is to give people
a little bit more dignity, too. So, wheelchair arms that have a whole
bunch of scraped paint on it, to some people that’s not good for
their dignity. So, that’s a real easy fix that really
improves the looks of a power chair. If you could just pan down,
on this same chair toward the floor. To get to caster wheels, to drive wheels, you might think that you actually
have to physically lift the chair up. It’s pretty easy and
I’m going to use a motor [LAUGH] as my, hopefully I can get this to work. But it’s pretty easy to
tip a chair on its side. This chair probably
weighs about 275 pounds. But with maybe 50 pounds of force,
you can lift a wheel up. Yes, I’m a big guy, but
you can slide something under. And it will hold that wheel up, okay? That was maybe 50 pounds of force, okay? You can get somebody to help
you if you can’t do that. Then you could access the drive
wheel very easily there, okay? You can do the same thing
with the caster wheels, but you don’t have to have serious equipment
to necessarily work on some of these simpler things like, replacing caster
wheels and drive wheels, okay? Gosh, that’s strange, but I think I’ve probably reached
the end of my [LAUGH] material. It seems like I had something else,
but that’s pretty much it. Are there no questions coming in? Okay, hopefully everyone’s still awake. [LAUGH] But I really appreciate your
time and if you have any questions, go ahead and reach me on the number or
the email at CReATE. And thanks for
participating in today’s webinar.

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