WheelchairDriver

Burgerman wrote:http://www.wheelchairdriver.com/board/viewtopic.php?f=2&t=8035

This is your biggest problem. As you recognise. post 1.

Failed on all 3 points, probably got more chance of a miracle getting hand movement back that I have of getting a joystick set up correctly. Just got to keep trying to sort it. Been considering a head mount with joystick mounted to that so it moves as my head bounces. Also looked at the Now Technologies gyro headset which they have got working for a wheelchair but not Dynamic Controls

I have a FTP setup, with solid state gyro in the headset. It controls the camera on a quacopter. Very easy to control smoothly. With a RC interface by woodygb that wold also work to drive a chair. And its wireless too.

This is what I mean. My goggles are showing me what the camera sees. But they also have a headtracker built in. So it has a 2 servo output. That could control a chair. Instead of the camera.


youtu.be/rFPNWiB2iiQ

re: brakes

I don't offhand know of a way to give the DX different braking delays when going uphill vs. downhill, but it may be possible to add some hardware that can do this. This is "off the top of my head" so may well be flawed, and it certainly lacks details, but you might think about whether this scheme could work.

First, you have to find whether the DX opens the B- or B+ side of the brake to set it, i.e. does it use a low side or high side switch. Turn the chair completely off and unplug the brake. Connect one lead of an ohmeter to one of the two brake contacts on the PM and touch the other lead first to the minus 24 V and then to the plus 24 V. If that pin reads infinite resistance (or at least very high resistance) when connected to both the +24V and -24V battery posts, that pin is the one being switched so with power off it is not connected to anything - it's the one to which the external hardware will be connected. If the other pin then reads low resistance (say 50 ohms or even less) when connected to +24V, but high resistance when connected to the battery minus, that pin is not switched - it is always connected to the +24V side of the battery - and switching is "low side". If that second pin reads high resistance when connected to +24V and low resistance when connected to -24V, it again is the un-switched pin, but it is permanently connected to battery minus and switching is "high side".

Let's assume that you've identified the switched pin (the one that is not connected to anything if power is off) and that the DX does "low side" switching. (Reverse the logic if high side switching.) You can now confirm this by re-connecting the brakes, adding a wire to the switched pin side, and connecting that to battery minus. If you've identified all correctly, this should make the brake release.

Now, what would we need to get quick brake setting going up hill, and delayed brake setting going down hill? What I suggest is setting the DX for up hill, and then using an inclinometer to override that for a time when going down hill. There are sensor boards that combine acceleration sensors and rate gyros, and a microprocessor (e.g. an Arduino) can be programmed to combine those to accurately measure pitch. If the pitch goes negative, we then have the processor close a solid-state switch to connect the switched brake line to minus (if low side switching) or plus (if high side switching) for a longer time (perhaps 2 or 3 seconds). During that time, even though the DX is saying "set the brakes" they will not be set. After that time, or if the pitch is no longer negative, the microprocessor-controlled switch is turned off, and stops bypassing what the DX is saying. So, here's what hardware would be needed:

1 pitch sensor board
1 small Arduino or other processor
2 high or low side switches rated for at least the current draw of the brakes (assuming that there are 2 separate brake coils, if there's only 1, or if 2 brakes are connected to one DX output, only 1 ss-switch is needed.) It would be best if these solid-state switches work on the same "side" as the switch in the PM; the processor logic could be inverted to use the other kind of ss-switch, but by using the same logic as in the DX a failure in the add-on leaves brakes working in normal DX fashion.

https://www.getfpv.com/fatshark-trinity ... odule.html

THIS is the head tracker electronics. Needs power, very little. And has 2 axis output. That would need mounting on your head. About 1 inch across.

Awesome technology.

Wow, way over my head on the technology but the head tracker idea could be one to explore (more accurately my friend to explore). I guess the stupid question is how is it connected to the DX system? I'm assuming that it would be easy to make a strap and pouch to fit it in, power from chair or depending upon how much it needs a battery. 2 axis will probably be just as easy as a joystick to configure in Wizard.

I need to go talk to someone who actually understands this.

Brakes might be a step beyond our knowledge

I guess the stupid question is how is it connected to the DX system?

Connect its 2 RC signal outputs to woodygb RC interface. And that is then your joystick! Good to go. One tiny board.
You could do the same thing using 2 tiny hobby rate gyros.

In fact 2 of these would be better as they are easy to adjust for sensitivity and are rate only. So zero or centre is already taken care of. normal RC pulse output. Because they give you your centrering spring electronically. Built in. Theres no reason that head position sensors need to cost phone numbers, this stuff is cheap and common in the hobby world.
https://www.ebay.co.uk/itm/Piezoelectri ... SwEUdaazjs

I'm assuming that it would be easy to make a strap and pouch to fit it in, power from chair or depending upon how much it needs a battery. 2 axis will probably be just as easy as a joystick to configure in Wizard.

It will be powered by the tiny woodygb RC interface. Instead of connecting a RC reciever, you simply connect that board. It will require an on off switch. So you can put the thing on your head. A velcro strap or something secure. Or your chair will run away as they fall off.

I need to go talk to someone who actually understands this.

As always, knowledge is power. Learn!!!

Brakes might be a step beyond our knowledge

Lennys method may work, if a little complex. But, the brake is working correctly. You actually have a traction problem going down. It can only come on if the wheel is stopped. So lower the deceleration time some so it slows more gently, or/and move more weight rearwards to get less weight transfer.

You are wanting the brake to NOT come on if it senses the thing is stopped. And then complain it does not work properly if you delay it! You cant really have it both ways. The other issue is that it on both wheels at once. Only one may need a brake on... So depending on terrain you will always need human correction input at slow speeds.

Burgerman wrote:How far does your 153Ah get you in that chair?

Hi BM, Never really counted. The most I have ever put back is 95ah, 30ah in the add-on 65ah main pack.
Got Turnigy amp meter on add-on pack so keep an eye on that. How I work it out is divide main pack by add-on pack gives me 2.18 so if its showing 20ah x 2.18 equals 43.6 on main pack. Sometimes you just know when to stop.

shirley_hkg wrote: How could he know ? He is the first to wear out .

Hi Shirley, Somtimes it feels like that

Easy. You go on a normal trip, and count Ah used if possible. If not, then count Ah put back, and reduce by 5%. Then look on your GPS phone app, to see didtance covered on the trip. Then do the math to work out how many Ah per mile.

You dont need to go till it is empty.

OK, I'll try and understand but have never been that good with electronics. If I get this correctly, board onto headstrap and 2 Woodygb rc interfaces. Does one of these then get plugged into the DX where the joystick is now? What were the ebay gyro modules for?

Learning at my age isn't easy I spend most of my day trying not to forget, my brain reached capacity a while ago.

Braking has to be a compromise especially with limited stick control, we'll alter the deceleration and see what impact that has.

OK, I'll try and understand but have never been that good with electronics. If I get this correctly, board onto headstrap and 2 Woodygb rc interfaces. Does one of these then get plugged into the DX where the joystick is now? What were the ebay gyro modules for?

Dont use the board. Use those 2 gyros instead. It will self centre and make it simpler to control.

When tesing you will need an AB and an open space. And when configuring, you will need the thing up on blocks so it cant drive off... The gyros need to be configured for sensitivity, and need to sit in the correct "plane"... As in they are unidirectional and may need input reversing to work the correct way. So left is left. And back head gives reverse. And need a user that can work an off switch just in case. Also woodygb interface needs the joystick, or a joystick, to connect inside where the joystick itself connect. You need an expert. And to talk to woody. It will need someone to prototype and configure. Still not sure if it will work best with the 2 rate gyros or 2 heading hold gyros, or that board...

Thanks, testing is kind of critical given my limited ability to stop it. My support workers have a remote kill switch with decent range after a close call with a drop into a ravine

The friend who would do the work is concerned on the risks and has already told me that extensive testing will be needed before he would be happy to let me loose with it. It can be a longer term project but if it works might be another option for high level quads. Will have to wait and see if he is happy to do it first.

@MichaelB: How are you transported from the bed to the chair/scooter and back? Do you have any special tool to do this job?

snaker wrote:@MichaelB: How are you transported from the bed to the chair/scooter and back? Do you have any special tool to do this job?

I get hoisted out of bed into my power chair, drive to my garage and get hoisted from power chair into the Boma. Coming home is the reverse.

When working away I get hoisted from hotel bed into a folding manual wheelchair, get pushed to the car park, Boma has been in the van overnight with batteries charged in hotel room. I then get hoisted from folding chair to Boma, drive Boma into the van then drive to wherever I need to be.

We have transfers down to a short amount of time but things like swapping my ventilator from chair to chair do slow it down.

I still have not imagined how you get hoisted yet Do you use an electric hoist?

MichaelB wrote:I get hoisted out of bed into my power chair, drive to my garage and get hoisted from power chair into the Boma. Coming home is the reverse.

snaker wrote:I still have not imagined how you get hoisted yet Do you use an electric hoist?

MichaelB wrote:I get hoisted out of bed into my power chair, drive to my garage and get hoisted from power chair into the Boma. Coming home is the reverse.

Yes, electric hoist, ceiling track in the garage and portable battery powered when travelling.

I am a quad too, maybe less severe than yours. I can move a little my left arm and use it to drive the powerchair. Until now my dad has to bring me from the bed into the chair and back, it is not easy. The difficulty is not only about weight or strength. But it is mainly because a quad lost almost muscles, the body is like a fluid bag. I have headache in finding a easier transporting. I found some hoist demo videos as below. But I see this kind of hoists does not well suit quad patients, at least in my situation. Is your hoist the same as the one in the videos? Can you post a link or a picture of your current electric hoist?
https://www.youtube.com/watch?v=cuPbwaC3oFI
https://www.youtube.com/watch?v=T5O7cdl3yNI

Why do they not suit?

Thats almost universal for quads?

I have no movement below my neck, all I can do is turn my neck from side to side and tilt it forward and back. I've used different hoists and never had a problem.

My portable hoist is similar to the one in the first video and ceiling track hoist is the same as the one in the second video.

I don't understand what your problem is, those 2 hoists are easy to use. Do you have the right size sling? Is the sling positioned correctly?

Hi All

A video from June. 30th London to Brighton Classic Car Run. Starting off from Greenwich park.
Lost sound track so posting with some music by Bach.


youtu.be/Fkvo5r0SWtQ

As a para, I generally transfer myself, but occasionally there are situations (usually health care related) where I have to be moved with a lift...

From the first time they used one on me back in rehab, I have hated the usual Hoyer lift sling - it makes me feel totally helpless and humiliated, embarrassed and frustrated.... I also find it quite physically uncomfortable... Minimal head support, bent around with my butt dangling and my feet up in the air, etc...

If I ever had to have a lift full time, I'd be more interested in one of the "Sure Hands" type lifts - I've done a test ride in one at one of the mobility shows, and it is seriously less embarrassing and uncomfortable. In short there is a sort of scissors arrangement of pair of arms that go around your ribs under your arms, and a pair of L-shaped hooks that go under your thighs... When they start lifting the arms squeeze gently (about like a firm hug) and pick you up with your legs supported by the hooks... You stay in about the same position you were when seated in your chair, even though there is nothing under you....

Unfortunately the Sure-Hands people are greedy jerks and won't sell just their lift arms, but instead insist on selling an entire lift or ceiling track system, which are nice units, but pricey and not significantly different from the ones everyone else sells... (I've been tempted to reverse engineer, but...)

Supposedly the arms will work on quads, and seems to me like it might be a better solution than the slings...

ex-Gooserider

This Sure-Hands system is really interesting. It looks simple but easy to use and comfortable

On google
https://www.surehands.com
https://youtu.be/Yeg2JS_Fzqg

shirley_hkg wrote: Any link to Sure-Hands product and videos ?

Mind the Gap, that was a lot of fun to see all of those cars. thanks!!

Hi All

Another video, speaks for itself.


youtu.be/5rBMfE3Hs7c

Thats because he is ignorant. And black. The black and muslim areas are always full of litter and worse. And are where the majority of crime, esp violent crime, rape, unemployment, very "extended" mixed up families, and other worse social and religous ignorance problems mostly are. They just copy what they all do in their own (shithole copyright d.trump) countries, where crime and suffering and ignorance are everyday life, the normal culture. They dont know any different, even if they were here living with their own parent (usually just the 1) for 3 generations. Thats one reason the rest of england voted to close the borders. BREXIT. And why many original native londoners moved out long ago. Leaving a multiculturaly "enhanced" left wing hellhole of "diversity" that is run by a muslim left wing terrorist anti jew pro muzlim sympathizer. I no longer even recognise it as a part of england. Its nothing like the rest of the country.

Only ireland, scotland, and the immigrants making up most of london voted to stay, the rest of us voted to shut the borders! Pretty clear here! Yet 2.3 years later we are all still waiting!