First Parts for the Real Wheelchair Arrived Today

It feels like we’ve reached an important milestone today as the first parts for the actual mountain going wheelchair arrived in the post.

I appreciate it’s just a length of tube and a flange, but eventually this will hopefully become the part that connects the rocker and bogie (or if you haven’t been following along – it connects forks for the front wheels to the frame).

I had devised some quite complex methods to connect the rocker and bogie which involved bearings and some complex configurations but it was getting really messy. If this basic flange method works then it will simplify things significantly.

The flange in the picture is about 0.5mm too big for the alloy tube so I still need to shop around for a better fit, but it is nonetheless exciting to think that I might actually start building the real wheelchair!

“Comfiest Seat Ever”

…is what Ada said when she sat on it :)

Here it is, the first full size prototype of the wheelchair seat:

I realise that it looks just a slightly scrappy ;) but that’s fine; this is just a tool for collecting measurements for the actual mountain wheelchair.

I can then take photographs and measurements and use them in the 3D environment to make sure the mountain wheelchair concept drawings have the correct dimensions:

The next step is to tweak the design to suit and then, carrying on with the pvc pipe, continue building a life-size model of the wheelchair.

Building a Full-Size Model of the Wheelchair

I’m reaching a point where I think I have all of the dimensions nearing completion for the 3D version of the wheelchair but it’s difficult to get a sense of scale when it’s just a virtual model on a computer screen. With this in mind, I’ve decided to build a full-size model out of PVC pipe.

Owing to the fact that this was the most important part that everything else needed to fit around, the first thing I wanted to make is the seat. To bend the pipes to the right shape for the seat, I filled them with sand which I’d baked in the oven, let them sit in front of the fire for a short while, then used rope to pull the pipes down into a wooden jig (see image below).

Taking inspiration from recumbent bikes, I then cut out bits of foam to match Ada’s body – adding or removing foam upon Ada’s request.

Mum is now sewing some material which can be stretched across the pipes to support Ada’s weight, and tomorrow, once the pipes have cooled down and settled into their new shape, Ada will be able to test the driving position of her wheelchair for the first time.

Free Give Away – Competition Time

It’s Competition Time!

And we’re giving away this unique, radio-controlled, six-wheel-drive, one of a kind, all terrain vehicle to one lucky winner.

We built this to see how our paper-based calculations of motor power and battery duration translated to the real world. Having now conducted our tests, this is a great opportunity to own something completely unique and support a worthwhile cause.

How to Win

In a few weeks we’ll be launching a fund-raising campaign for our Mountain Wheelchair project and we’re looking for fund raisers to help our cause. The winner of this unique gift will be the person or group who raises the most.

What you need to do

At the moment, we’re just trying to see who’s interested so please get in touch, and if possible, share this post on social media to help increase support.

When we launch the campaign we’ll be in touch with details of how to get involved.

Fat Wheels are Too Fat!

In a previous post I’d demonstrated that wheels from a fatbike where the most aesthetically pleaseing on the wheelchair. Unfortunately, they’re too fat.

I tried to revisit some of the measurements I’d taken during a trip up Snowdon but all of my pencil notes had become eligible. Luckily however, part way up the mountain, I recorded myself saying that the wheelchair needed to fit through a 3′ gap. That’s 36 inches in total.

The fatbike wheels are 4″ wide, so 8″ for both sides. 8″ of the 36″ available space is too much. It would mean that 22% of the wheelchair width was just for the wheels. For that reason, I’ve had to revert to standard mountain bike wheels.

In addition to this, the seat was taking up too much room too, so I’ve had to redesign that also.

Here is the current mountain wheelchair concept drawing which will now fit through a 3-foot gap:

The only problem with this is that having a smaller wheelbase means it’s more likely to tip over on its side.

I plan to overcome this by moving all of the central parts of the frame lower down. it does mean that it will have a lower ground clearance, but that’s preferable to a wheelchair which falls over all the time.

On the plus side, this does mean that the wheels will be lighter.

Mountain Wheelchair Concept Update

I’ve been updating the concept drawing of the finished mountain wheelchair so that it is now to scale and working out how some of the parts are going to fit together. One of the obvious changes I’ve made is the addition of fatbike wheels:

Trying out different wheel options in the drawing, these fatbike wheels are certainly the most aesthetically pleasing. For comparison, I’ve included some of the lesser options below:

What an Incredible Week!

It’s been an absolutely amazing week, not in terms of wheelchair progress, but in terms of Ada’s achievements.

As I’ve discussed before, many people who suffer with M.E. also suffer with depression. In an attempt and prevent this from happening to Ada, she’s been setting herself goals. Some are little goals like spending time with friends, some are a bit more challenging, such as getting up and down the stairs by herself, and much to my delight she set her ultimate goal as getting to the top of Snowdon.

As we were driving home from her Wednesday appointment I decided to take charge, kidnap her for the week, and put some real effort into helping Ada achieve her goals.

The next evening we had the first goal ticked; swimming. Whilst in the pool, not having to use her walking sticks or being confined to a wheelchair, I imagine she might have felt like she was an equal. From the moment she got in until two hours later when I’d said for the tenth time “it’s time to get out”, Ada was grinning like a Cheshire Cat.

The next day she attended her first lesson with a home tutor and managed to get up and down the stairs all by herself, not once, but twice. Another two goals ticked.

When Saturday arrived there were no signs of delayed onset muscle soreness from the swimming, in fact, she seemed more lively than she had done for a long time. It looked like she was feeling the benefit of the exercise. She even went to the park with her friend and the two of them sat on the swings chatting for an hour. Considering how isolated she’d been feeling this was quite a breakthrough and another item crossed off the list.

Improving on the previous day’s goal, another of her aims for Saturday was to go up and down the stairs four times. This was easily achieved and she was showing no sings of additional soreness or tiredness.

Sunday was the most important day though…

Finally, I’d pulled myself away from the mountain wheelchair project long enough to realise that it was high-time I went up into the loft and retrieve the Christmas decorations. I carried Ada up the stairs and plonked her on the landing as I prepared to open the hatch to the loft.

Having never been in a loft, Ada asked if she could come with me. I asked her how she expected to get up and down the ladder to which she replied she’d use her walking sticks. “It’s a ladder Ada”. When she said she could just walk up, I asked how she’d get back down again. She said she’d come down on her bum. “It’s a ladder Ada!”. Not put off by the ladder, Ada climbed up. This in itself was amazing, but not as amazing as what happened next.

She climbed back down the ladder without difficulty, stepped off the bottom of the ladder and started talking to me. I looked at her in amazement wandering how long it would take her to realise. All of a sudden her expression changed; her jaw dropped and her eyes widened. “I’m standing!” she shouted.

Ada was standing up! And with out any support.

She was so happy when she realised she was standing up that she couldn’t hold back the tears!

Mummy arrived later that evening and was asked to sit down and brace herself. When Ada stood up and started doing star jumps there were more floods of tears.

Remarkably the next morning (which is when she’s usually at her most sore), she woke up, stood up, and walked into my bedroom happier than I’ve seen her in a long time.

Today was going to be a good day! The sun was shining, I had time off work, and Ada was walking! Opting to make the most of this opportunity we packed the climbing gear in the car and set off in search of a cliff-face.

It’s been so long since Ada’s done any climbing I thought it would take her several attempts to pluck up the courage and drop herself over the edge of the cliff. Without hesitation she dropped over the edge, smiling all the while. “Again” she shouted when reaching the bottom.

I carried Ada back to the top of the cliff where we sat, admired the view for a moment and prepared ourselves for another abseil. In that moment, I’m not sure which one of us was the happiest.

Funds are Raising

Wow, what an incredible surprise! Yesterday, out of nowhere, £200 was donated to the website! In addition to this Mummy held a raffle at the Surf Snowdonia Christmas Market last weekend and raised £243.80 towards Ada’s Mountain Wheelchair!

Ada hasn’t been to school or seen her friends for 8 months now and has been feeling quite isolated. Until quite recently she hasn’t really taken a great deal of interest in the project and I think this is because she questions whether or not her stupid step-dad will be able to do it. Showing her the support we received yesterday really helped to lift her spirits. From all of us, a huge thank you to everybody who has offered their support and shared our cause on social media.

Mum will be running another Raffle this Saturday at the Christmas Fun Day at Bodafon Farm Park to try and raise some more money for Ada’s Mountain Wheelchair. If you’re in the vicinity then it would nice to meet you all.

A Compact Differential Bar

Just a quick update on differential mechanisms. In previous posts I’ve looked at different types of differential mechanisms such as geared differentials, and hydraulic differentials and various differential bars using ball joints. It’s since become clear how important weight reduction is going to be and for this reason, for the smaller prototype, I’ve made a version which has a differential bar which is almost identical to the setup on the Mars Rovers.

Of all the methods I’ve tried, I think this one is most suitable for the final mountain going wheelchair owing to how compact, light and durable it is. Initially I’d avoided this method because I thought it would interfere with positioning of the seat but now armed with a concept drawing of the what the finished wheelchair might look like, I can see that this isn’t going to be the case.

The cheap motors on the smaller prototype are starting to malfunction so once they’ve been replaced I’ll upload some videos to show how this new differential is working out.

This page was last updated on April 18th, 2018 by .
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