Would this work? Engineers, shoe makers and Physios please

Nick, put me down for a pair if it works,

also, i use superfeet green in my fused side shoe. tilts foot in slightly.

Lee Short (not a member on here - a runner if I recall) is a decent podiatrist in the York area if you want a professional opinion.

Used him to help my running.

More use to Ton I suspect.

How are you planning to allow the tubes to change volume? What will they be made of?
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what happens when you need to turn round and walk back along the same camber? </span>

ton - I have looked at various insoles like that and they help keep the foot supported but they don't help with off camber surfaces.

The trouble with my foot is I stubbed my big toe quite hard which snapped the bones and broke the joint where it meets the fused ankle. This also pushed the other toe bones out of line and snapped a couple of those so there is not much strength along the length of my foot and pretty much all my weight and balance depends on my big toe now.

As I said, I stubbed it quite hard

Would a gently curved sole across the width of the foot, like you were standing along the length of a 1/4 pipe, achieve the same without needing the complexity? Essential cambered in both directions?

Interesting concept.

To expand on a previous comment, I think you’d need a rather soft foam sole, to support the flexible chambers.

Also rather than a valve, if you had a suitably sized orifice between the two chambers, and the connecting tube was blocked every time you put your foot down/applied a force, I think you could have a rather stable shoe which could adapt to different cambers in a footstep or two.

Not sure on longevity of all though, but I guess Nike manage.

Edit: thinking about it, the two chambers would equalise in pressure, so al a long as the flow rate between them is controlled, it could be quite stable anyway

Curved style doesn't give much support to the foot as it will roll from side to side. I want a solid, flat platform for the foot and a solid flat platform touching the ground but the two solid flat platforms are not Alsager parallel and the angle needs to automatically adapt.

I am not sure if the exact material for the two tubes but something like a bike innertube would work in principle.

I am thinking that there would be a hard wearing layer for the boot that touches the ground and for the inner sole with the soft material sandwiched between. It would this be protected from wear and tear and just get squished.

The idea of the valve was just to control the flow rate between cylinders. The liquid viscosity would help but different people weight different amounts and you may want to carry the shoes with which it adjusts.

My question would be if this works as intended, will it now feel a bit like a curved sole anyway?

Perhaps the valve or connecting link could be limited to only allows a tiny amount of fluid to transfer so it takes several paces for it to adapt to a new camber. I'm thinking the best point to allow the two sides to equalise fractionally would be when you start to lift your foot, because the ball of your foot would be fully weighted and as you lift your heel a squishy valve would open to allow say 5ml to transfer before a check valve/flap blocks the rest until the next step.

I am trying to work out how best to implement the valve. Basically I want it locked when you have your foot on the ground so that it is nice and stable but able to adjust to the camber at the same time. This isn't possible because of the damned time continuum.

I am thinking that as you first put your foot down there will be maximum pressure as the heel strikes the ground so use that part of the footfall to push the fluid through the valve. Then as your whole foot touches the ground the overall pressure is reduced as the load is spread so the valve closes and you have a locked sole position.

I am guessing this will take some fairly fine valve adjustment to judge the pressure for, perhaps, the first third of a foot fall while the level and angles of camber exert their influence and then being able to close after that. Liquid viscosity and valve tuning will take a bit of playing with I suspect but it seems possible.

I think this might also help people who feet are not level and who feel like they are always working on a camber.

A bit more thinking and STW design work here and I might actually have something worth trying although I am not sure my garage has all the required tooling, yet.

I am trying to work out how best to implement the valve. Basically I want it locked when you have your foot on the ground so that it is nice and stable but able to adjust to the camber at the same time. This isn’t possible because of the damned time continuum.

I am thinking that as you first put your foot down there will be maximum pressure as the heel strikes the ground so use that part of the footfall to push the fluid through the valve. Then as your whole foot touches the ground the overall pressure is reduced as the load is spread so the valve closes and you have a locked sole position.

I was imaging it was a non return valve. In effect you would create a pump that pushed fluid from the small to the large chamber. You would then need a return loop. - This would only work in one direction. You would have to walk back on the otherside of the road!

I want it bi-directional so I can walk on either side of the road or evev along the seafront without having to catch a ferry across the channel to walk back 🙂

I want it bi-directional so I can walk on either side of the road or evev along the seafront without having to catch a ferry across the channel to walk back 🙂

You want a valve that remains closed when you lift your foot and open when it is on the ground otherwise the 2 chambers will act as one and equalise their pressure everytime you lift your foot.

If you use an orifice the flow speed is the same in both directions so when you lift your foot the fluid will flow back at the same speed as it entered the larger chamber.

Maybe a normaly closed valve that can be opened when the shoe presses down and springs closed when the shoe if off the ground. Not sure if this will work as the vavle is balanced so fluid could flow either way?

I think the time difference between the uphill tube and downhill side hitting the pavement will be very short, so I'm not sure there will be enough time for the fluid to move from one side to the other, especially as the valve or orifice will also restrict flow.

But good idea.

Re curved sole...

as it will roll from side to side

But would it though.... As I thought your problem is that the ankle CAN'T roll (invert/evert)!

DrP

? Won’t it be impacted by where you put the weight on your feet ? (*I have no idea)

As an alternative what about just one tube on the outside that runs up your leg, to your pocket, with a sort of syringe or compression on off device, so you can pump it up to suit , it would be cheap, nasty but possibly provide sort of proof of concept.

[i]But would it though…. As I thought your problem is that the ankle CAN’T roll (invert/evert)![/i]

That is the problem but the effect is that if the foot is not on a level surface my leg and therefor body gets tilted to one side and I end up walking that way. Having a 1/2 tube on the sole will basically mean I am walking on a very thin central bit with the chance of it rolling in either direction at any time so I could fall into the shop front instead of the road.

All - both tubes will be the same size but either could be inflated or deflated depending on how much fluid is pushed in or squeezed out.

I agree with Richmars point about the time the fluid will have to move. That is my main issue I think. How do I get the shoe to self-level quickly enough for the foot to be level and also stable when my full foot is on the ground. I am now wondering about making it very thick liquid so when I step down it is squeezed to make it level but very slowly and then will remain like that until the next step when it will get squeezed again. This means it will always be one step behind in terms of adjustment but as pavements don't change camber that rapidly it might not be a problem.

I might need some material scientist to join the thread to suggest the material for the tubes and a suitably viscous liquid.

Yes to viscous fluid, in effect it wants to be heavily damped and lightly sprung, like when there is too much rebound and your fork packs down. Unless you envision some pavement angle sensing radar the shoe will have to react to the change of angle rather than predict it, but if subsequent steps are levelled up your course deflection will be minimised I'd imagine.

I see what you're tring to do, but I don't think this will work easily. Your desire basically is to keep your foot on a horizontal surface, or at least laterally flat.
1You need to put down your foot flat exactly else you'll start pushing fluid around where you don't want it, and you say you weight bear on your big toe.
You want a viscous fluid, you think, but there are a lot of variables flying around. I don't like the idea of valves, and I'm wondering what fluid is going to work summer and winter.

You could try something like a Nike with a big air bad, as that can do this if you can tolerate the side force on the foot.

wbo - I also have my doubts which is why I shared the idea and asked for input. the good thing about having the foot fused is that is basically just a fixed bit of my leg bent at 90 degrees so it will always be put down 'flat'. The only angle that will change is the ground.

I started trying to design something like a bike pedal turned around 90 degrees. If you think about it, with a pedal, your foot can remain ad the fixed angle regardless of the angle of the crank arm. The troubles with trying that is that it has a single pivot, like the half pipe idea mentioned above, and there is nothing stopping the pedal spinning when I want some fixed stability. That is when I moved across to the two tubes of custard idea before remembering that custard in a non-Newtonian fluid so some other thick fluid would need to be used, perhaps gravy?

The valve is only there to allow adjustment of flow rate for thin or fat people, hot or cold affecting viscosity and wanting or not wanting the effect etc.

re the nike shoe idea. they dont work, far too soft causing the fused foot to roll out wards at the heel.
comfiest and most supportive shoe i have found is keen targhees. got boots and shoes. i can almost walk normal in them until i get on offcamber stuff.

Slightly modified design diagram to cope with the foot angle, front to back, when walking. When the heel strikes, the fluid will get pushed into the front of the shoe, plus side to side as before, but as the leg moves to the straight up, the fluid will even out front to back and then finally get pushed to the back as the step concludes.

I have also changed the side to side flow to a few narrow interconnections but I think that an adjustable valve of some description will be required.

I wonder if you could achieve the same affect with a memory foam type material with a slow rebound property.

The trouble with foam like material, I think, is that to prevent the spring back, they have to be slow to squash. That is why you get uncomfortable 'pack down' when having sex on memory mattress. Also, there is much less control for lateral balance

Thats xray makes my feet ache just looking at it.

Can't the bones be realigned?

As for your shoe idea, wouldn't a MIPS style insert into the shoe work better, allowing the ankle to rotate in the shoe like a 'ball and socket'?

This pretty much supports my idea.

https://zcoil.com/fused-ankle/

There must be another make that looks more 'normal' but works similar.

You could add a carbon fibre supported insole for your metatarsal issue. I rode a 100 mile sportive only a few weeks after fracturing 2 of my metatarsals as my carbon fibre road shoes were so stiff and supportive. Couldn't wear soft soled shoes or trainers for months after injuring it, it was only either my steel soled work boots or stiff cycling shoes that didn't give me pain.

Good luck OP on your recovery.

My general approach to any problem now is that with 8 billion people, nothing is unique, somebody has already tried to solve it and the solution will be on the web. But you need the right names for things to put in the search.

The inserts that are made to adjust shoes to cope with injured feet are known as orthotics. Skiers often have a 'cant' adjustment in their boots so that their skis sit flat on the snow. What I think you want, then, is self-adjusting canting orthotics. So far, I haven't found anything, but sharing the approach in case you can.

Stiff carbon inserts are a definite plus for supporting the foot in the shoe. That was my thought for the insole but they don't sort the camber issue.

MIPS style would let the ankle rotate inside the shoe except the ankle doesn't move. Think of it as a simple bone extension of the leg. I have more than the average number of legs but less than the average number of ankles. This is from 5 years ago after the last operation when they removed a couple of bolts from the anlkle and added the long one to hold the heel on and the front one to connect the front of my foot.

That shows the heel is quite elevated but it is not as extreme since stubbing my toe as I basically broke all the joints one forward from the bolt head and the foot flattened a bit as they didn't put a cast on it and walking around made the bones set at a depressed state.

I have googled the idea many times in the last 11 years, 6 during the six operations to get the foot to actually stay on where I was mostly looking at inserts and 5 since the last mostly successful operation where I was trying to get some movement in the sole of the shoe itself but without success. Happy to follow any link you can find that might help. I had seen the Z-Coil but was looking for something slightly less 'special' looking. I guess I could go for that as a heel design with something like my idea for the front of the shoe.

But the squash is loaded and the rebound unloaded. Isn’t the packing down what you want in this situation?

If the 2 chambers are soft enough to allow expansion and contraction I think you will have a problem with lateral stability anyway.

I'm an electronic engineer so may have the wrong end of the stick and have no knowledge of fluid dynamics but wouldn't some kind of gel filled bladder work?
Like one of those gel ice packs but the right size and a thicker gel?
Would allow the gel to disburse slowly to allow your foot to match the camber of the ground. I'm not sure what the advantage of the chambers etc are.

Not sure this could ever be a thing. What you are basically saying is if you put greater pressure on the uphill side of the shoe the fluid would be forced into the part of the bladder/tube/vessel that has the lesser pressure - i.e. the downhill side. So far so good. However its only the low pressure side of the shoe whilst your are 'edging' and putting greater pressure on the uphill side. The very premise of what you are trying to do is be able to then spread your weight evenly across your foot and walk comfortably. As soon as you do that the pressures on the two sides of the shoes would go back closer to equilibrium and the fluid would redistribute.

I think the only way you'll achieve what you want is if there is some sort of smart (electronic) or dumb (human) intervention open and closing a valve. The dumb approach would be you looking ahead and seeing a long stretch of cambered walking, 'edging' your foot to induce fluid imbalance and then closing a valve to maintain that imbalance. When you got to flat section you'd have to open the valve to redistribute. A smart system could use some sort of strain gauge to register if the foot was flat to the floor, then an inclinometer to measure the camber whilst the shoe was mirroring the surface and then open and close a valve based on that data on the next foot step in an attempt to push the fluid into the right chamber and flatten the shoe.

A very (very) basic solution might be to adopt some sort of bastardised version of the system used in ski touring bindings. When 'skinning' (basically skiing uphill with gripping skins stuck to the bottoms of your skis). Touring bindings have metal platforms you can flick down as effectively heel risers. The steeper the hill ahead, the higher the platform you engage. Obviously that works by effectively altering the pitch front to back. You could probably cobble up a system that changed the roll, adding a bit of extra sole on either the inside or outside of the shoe. Could be as simple as a piece of rubber with a neodymium magnets embedded within and corresponding magnets embedded in the sole under the fist metatarsal. Keep it in your pocket on the flat and then clip it onto the sole of the uphill shoe on cambered pavements.

Stiff carbon inserts are a definite plus for supporting the foot in the shoe. That was my thought for the insole but they don’t sort the camber issue

That wasn't what I was meaning. I'm fairly sure that orthotic inserts exist to manage what you call camber and what (from ski boots) I call cant. As you say though, if your shoes are laterally cambered too much, you'll turn/fall away from the kerb, so you want self adjusting ones. I would find somewhere that does orthotic inserts and phone them; if they don't have what you need at they will know what it would be called if it exists.

It does occur to me, however, that it might be easier to manage a camber towards your good leg, rather than away from it, and if you can't find or make adjustable cant shoes, it might be worth trying a fixed cambered insert.

I was reading the link to the zcoil shoe above and saw the term "rocker soles" so googled it. You may be already familiar with them or even use them to help with forward motion but I think a simillar thing might help with cambers i.e. a radius across the sole. Similar to the half pipe idea mentioned above but a more gentle radius, made from a material that would flatten slightly on contact. If your foot really is a rigid extension of your leg then I imagine this could be quite stable. I am certainly no expert though.

I have more than the average number of legs

Honestly?

Could be as simple as a piece of rubber with a neodymium magnets embedded within and corresponding magnets embedded in the sole under the fist metatarsal.

I like that idea as a proof of concept to see if offering an adjusted cant would make walking on the angle easier, if it does, then you can then look to improving the system.

However, have you seen the pictures of the x-rays in the thread? Could be a bit exciting with some neodymium magnets near those!

Hi, I just wondered if you'd seen these? They may not be thick enough to make the difference you're looking for though.

liqua care diabetic flowgel insoles

Just some stronger versions of these right?

In all seriousness though, I can't see how a viscous liquid flowing between multiple chambers would be able to react and adjust fast enough with every step that it wouldn't feel like walking on a bag of water.
I'm procrasinating, so I just timed myself - 12 seconds to walk 20 steps. That's 10 steps on each foot. So 1.2s between the same foot striking the ground which it's probablyin the air for half of that. 0.6s to hit the ground, adjust to level and feel stable before starting again.

But, why stop with simple fuid dymanics? You should be going for opposing electromagnets with inclinometers and pressure sensors in the soles with instant power adjustment to maintain a level foot as the shoe hits the ground. Just need to remember to plug your shoes in to charge every night.

These reservoirs and channels would have to exist as voids in squishy foam. I wonder if you could simply have the channel be at the top of the foam bit near your foot? Maybe covered by a hard bit of plastic. Then as the shoe hits the pavement inside first, fluid would flow from the inside chamber to the outside one, which is currently unloaded. Then as your full weight hits the shoe the foam deforms, and the hard plastic squishes into the channel blocking it. The valve would have to be at the heel end. I think maybe you'd need several separate reservoirs, maybe, not just one long one down each side.

Grab some cheap trainers (with a thick sole), disassemble them with a heat gun and try it out.