Measuring pressure on pedals in addition to EUC tilt (?)

[null]

To split of the off topic from the Veteran Abrams thread:

Larger tyre EUCs feel more sluggish due to the foot to tyre diameter ratio needing more force to tilt the wheel. The EUC also doesn’t know anything of the terrain, thus more effort is required for uphill or bumps.

What if the input wasn’t only the EUC tilt, but also how much pressure was exerted on the front or back of the pedals? That would allow to separate the EUCs actual angle and the effort input of the rider.

We’d need a good programming to dose the two inputs, but as I see it it might allow larger EUCs to accelerate easier, or at least compensate for terrain demanding extra effort.

I’m still not sure if there is some logic flaw here (feedback loop?), but throwing out the idea as it would be fairly simple to implement.

The point would be: the firmware taking into consideration the EUC tilt, but also the actual user pressure input.

Edited August 5, 2021 by null

[Silver]

Even if you are putting pressure on the front of the pedals too much acceleration will still cause you to fall backwards. 

There are software things you can do but it has to be things like tilting pedals forward to give you more leverage or something.

[null]

28 minutes ago, Silver said:

 

Even if you are putting pressure on the front of the pedals too much acceleration will still cause you to fall backwards. 

No more reason it would leave without you than when using only angle to accelerate: the moment it passes in front you are no longer putting pressure on the front of the pedals.

edit: here is weight pressure used to accelerate / descellerate a PEV, without it riding out in front without the user.

Edited August 5, 2021 by null

[Silver]

3 minutes ago, null said:

No more reason it would leave without you than with using purely angle to accelerate: the moment it passes in front you are no longer putting pressure on the front of the pedals. Besides; it wasn’t suggested as the sole input, but as a supplement to EUC angle.

If that's the case then wouldn't it just not do anything at all?

[null]

53 minutes ago, Silver said:

If that's the case then wouldn't it just not do anything at all?

Currently only angle of the EUC is considered: when you ride on a flat terrain you push forward a certain amount and the EUC accelerated accordingly. If you meet a (larger) bump and keep the same pressure you will fall off, because you need more force to push the EUC to the same angle. So you put more pressure to compensate for the bump. The EUC knows nothing if this, only that it’s angle dictates it’s acceleration.

if you had the pressure on the pedals as a separate input, you could theoretically meet the bump without having to push harder: the EUC measuring that your input is the same, would compensate the climb by itself, without needing you to push harder.

It should probably help compensate for the harder push required for uphill, for pure acceleration or to compensate tyre size, that is the question..

Edited August 5, 2021 by null

[.....]

This sounds like an interesting idea and possibly the most wonderfully dangerous thing I've heard all week.

Edited August 5, 2021 by ShanesPlanet

[xiiijojjo]

To me as long as proper programming and testing is done and the programmers figure out the priority of this secondary data in relation to the main data (the angle of the euc) it could potentially be done very safe and with the intended effect. 

Another added benefit of weight sensors in eucs is the potential to turn off the motor in the event that they no longer sense weight (a crash has occurred) but i guess we have the 40 or 45 degree lean cut out safety measure nowadays. 

One thing that makes me doubt whether this is the solution to my issue of wanting aided acceleration is the fact that this system might not be so good if jumping is involved. 

[bracky72]

23 minutes ago, xiiijojjo said:

 

Another added benefit of weight sensors in eucs is the potential to turn off the motor in the event that they no longer sense weight (a crash has occurred) but i guess we have the 40 or 45 degree lean cut out safety measure nowadays. 

 

This particular feature crashes a lot of onewheels. 

[RockyTop]

15 hours ago, null said:

To split of the off topic from the Veteran Abrams thread:

Larger tyre EUCs feel more sluggish due to the foot to tyre diameter ratio needing more force to tilt the wheel. The EUC also doesn’t know anything of the terrain, thus more effort is required for uphill or bumps.

What if the input wasn’t only the EUC tilt, but also how much pressure was exerted on the front or back of the pedals? That would allow to separate the EUCs actual angle and the effort input of the rider.

We’d need a good programming to dose the two inputs, but as I see it it might allow larger EUCs to accelerate easier, or at least compensate for terrain demanding extra effort.

I’m still not sure if there is some logic flaw here (feedback loop?), but throwing out the idea as it would be fairly simple to implement.

The point would be: the firmware taking into consideration the EUC tilt, but also the actual user pressure input.

By definition you want it to go more with less pressure. That means less leaning and more go. That means that you are not leaning enough for the acceleration requested. That means that you have changed your request from keep the pedals level to just spin faster. That means forget about keeping the pedals level.
These things have absolutely no intention of moving in any direction at any speed. They just want to keep the pedals level. We take advantage of this OCD situation by leaning and upsetting the balance. The wheel is forced to move because that is the only way to keep the pedals level. We don’t need a pressure switch. The wheel for the most part already knows that we are leaning forward. That is why it started to move. You just want it to move more. That means the pedals would tilt-  no longer be level. 
 

Unless you are talking about pedal dip or soft mode. We already have that. 

[xiiijojjo]

@RockyTop I think you are misunderstanding @null and myself. We fully understand how an EUC works and why it is limited in the way it is in regard to amount of lean required. 

We are simply having discussion about the innovation and mechanisms required to take it to the next level. 

40 minutes ago, RockyTop said:

Unless you are talking about pedal dip or soft mode. We already have that. 

What we are talking about is indeed very similar to the soft/medium mode pedal dip in the sense that we want assistance with acceleration.
But instead of having the assistance depend upon power leaning, we want assistance that effectively removes the need for extreme leaning in either direction. 

 

[RockyTop]

5 minutes ago, xiiijojjo said:

@RockyTop I think you are misunderstanding @null and myself. We fully understand how an EUC works and why it is limited in the way it is in regard to amount of lean required. 

We are simply having discussion about the innovation and mechanisms required to take it to the next level. 

What we are talking about is indeed very similar to the soft/medium mode pedal dip in the sense that we want assistance with acceleration.
But instead of having the assistance depend upon power leaning, we want assistance that effectively removes the need for extreme leaning in either direction. 

 

Let’s say that you want to go up a hill at 15mph without putting pressure on the front of the pedal. You could program the unicycle to do this. You would have to stay perfectly rigid. The unicycle would first go backwards to lean you forward, then it would take off forward keeping you at a set angle. It would be like a robot balancing a stick on its finger while running up a hill. You as a driver would not have any control of the speed. I also question steering.
 

If the wheel was omnidirectional and programmed with self navigation............. anyone have Elon’s phone number? 

 

 

[conecones]

I get that the idea is to have the pressure sensor be a sort of "force amplifier" for a set amount of lean/pedal pressure, but this doesn't seem viable due to Newton's 2nd law because the part you stand on (stator) is connected to the rotor via free-spinning bearing rather than say a gearbox or some mechanism where input/output forces can be modified electrically. In essence the EUC as currently designed must be in equilibrium during operation.

To offset this equilibrium by adding a force multiplying sensor would mean the motor would overpower your ability to lean forward the moment the pressure sensor kicks in. In other words the force you apply to the pedal will be met with a greater opposite force and thus swing the pedal backwards making you brake. Basically you will not be able to accelerate any faster with a pressure sensor than without it because of this negative feedback loop due to the stator and rotor being separated by a free-spinning bearing. The pressure sensor and the gyroscope will be fighting each other within this a net-zero system.

[mrelwood]

 

On 8/6/2021 at 12:35 AM, null said:

The EUC also doesn’t know anything of the terrain, thus more effort is required for uphill or bumps.

That’s not the reason though. More effort is required because of geometry of an incline, not because of what the EUC knows or doesn’t know.

On 8/6/2021 at 12:35 AM, null said:

What if the input wasn’t only the EUC tilt, but also how much pressure was exerted on the front or back of the pedals? That would allow to separate the EUCs actual angle and the effort input of the rider.

Not really though. You are not considering the fact that the EUC is a self-balancing entity.

On 8/6/2021 at 12:35 AM, null said:

it might allow larger EUCs to accelerate easier, or at least compensate for terrain demanding extra effort.

How would the wheel compensate for it though? Accelerating any more or less than the current system does would result in tilted pedals. I don’t think that’s what you want to do though.

On 8/6/2021 at 12:35 AM, null said:

I’m still not sure if there is some logic flaw here (feedback loop?)

Exactly. Your thinking about the acceleration aid would work in a non-self-balancing system. It could be that the stability we feel on the EUC fools your train of thought.

 The only thing the wheel does is to spin the motor in order to keep the pedals level. Spinning of the motor and the pedal angle can’t be separated. Either the EUC tries to keep the pedals level, or it doesn’t. It can’t keep the pedals level and spin the motor a bit more at the same time.

 

23 hours ago, null said:

No more reason it would leave without you than when using only angle to accelerate: the moment it passes in front you are no longer putting pressure on the front of the pedals.

At which point you are no longer accelerating at all, since the EUC has now canceled your forward lean. 

23 hours ago, null said:

edit: here is weight pressure used to accelerate / descellerate a PEV, without it riding out in front without the user.

That’s not a self-balancing vehicle. The logic of operation is completely different.

I had the chance to try an e-longboard a few weeks ago. It was a disaster… Trying to match the level of the acceleration dial under my thumb to my forward lean was completely unintuitive to me, and felt like the whole system was an ancient prototype.

 Point being, separate the amount of power applied to the motor and the rider’s forward lean, and the system simply doesn’t work on a self-balancing system.

 

23 hours ago, null said:

If you meet a (larger) bump and keep the same pressure you will fall off, because you need more force to push the EUC to the same angle.

Why would you need more force to push the EUC to the same angle?

23 hours ago, null said:

So you put more pressure to compensate for the bump. The EUC knows nothing if this, only that it’s angle dictates it’s acceleration.

Maybe think about riding over a bump as a video clip, shot from the side. Then inspect the event frame by frame:

1: Flat ground, a light forward lean to compensate for the wind resistance, stable speed forward.

2: You meet an incline. Your body’s kinetic energy has caused a steeper forward lean (falling forward), and more pressure at the front of the pedals, causing the EUC to tilt forward. What does the EUC do then?

3: The EUC has increased the power to the motor so that it would again be balanced and upright, pedals level.

 What part of this equation would you change?

23 hours ago, null said:

if you had the pressure on the pedals as a separate input, you could theoretically meet the bump without having to push harder: the EUC measuring that your input is the same, would compensate the climb by itself, without needing you to push harder.

So, what would the wheel do with this data from the pressure sensors exactly? It can’t accelerate more because the angle of the pedals would change.

23 hours ago, null said:

It should probably help compensate for the harder push required for uphill, for pure acceleration or to compensate tyre size, that is the question..

Remember, a self-balancing vehicle never has the intention of accelerating to go forward. The only thing it tries to do is to keep the pedals level. Any change to the power applied to the motor (compared to the current EUCs) would result in tilted pedals. 

[Planemo]

I do get 100% where null is coming from with the idea, but I'm with conecones and mrelwood on this. I can't see how it would work.

If we are saying that pedal pressure (via a sensor pad or similar) is going to act as a multiplier to induce acceleration, lets take this thought process to the next step - lets do away with the current way EUC's work and omit the pedal angle input altogether and just run a 'super multiplied' pressure system on it's own. Are you saying the wheel will still be rideable?

I'm pretty sure it won't be. I vote we give it to @ShanesPlanet to be a test pilot though. I'll deffo buy popcorn for that one.

[null]

1 hour ago, Planemo said:

If we are saying that pedal pressure (via a sensor pad or similar) is going to act as a multiplier to induce acceleration, lets take this thought process to the next step - lets do away with the current way EUC's work and omit the pedal angle input altogether and just run a 'super multiplied' pressure system on it's own. Are you saying the wheel will still be rideable?

I’m not saying the EUC should solely base on pedal pressure for balancing, but that measuring that input as a complement to EUC tilt would allow the algorithm to have user intention as an additional set of data.

@mrelwood I generally value your input but considering how you seem to think I don’t realise a EUC is a self balancing vehicle I find it fairly insulting to my intelligence. You take every point I make as if I where totally retarded and have no understanding of how a EUC or basic physics work. I won’t waste time replying further, think of it what you will.

(edit: seeing how you spent a longer post to tell meepmeepmayer that a EUC with more torque didn’t accelerate faster (*with the same riding style (well duh)) I have to believe that you either take people for idiots or argue in bad faith.)

@all I don’t see any fundamental logical argument against my proposition till now, only assumptions on crappy implementation that would have killed the concept of EUC before it was born.

I truly don’t get that the concept of separating user input and EUC tilt as two separate data should so difficult to either grasp or imagine the use of.

@Planemo @ShanesPlanet could totally be, never excluded, hence the post

Edited August 7, 2021 by null

[xiiijojjo]

In any case all this talk has inspired an even greater interest for me in a  theoretical RS HS stuffed into a 16 inch form factor for comparing to the RS HS as this may be a temporary solution for the likes of me until EUC innovation has gone a lot farther.

No matter how i try to consider how this proposal of null and i would work (assisted acceleration/braking requiring less leaning), i just can't seem to come up with a concept/design that would be viable without contradicting physics. At least not for now and from what i've read in this thread and around the forum there doesn't seem to be any modern solution to this. (keep reading i was writing this post for 1h+  and had some time to think)

 

For now these seem the most viable current solutions to ultimately requiring less aggressive leaning to achieve, what at least feels like, assisted acceleration/braking.

• Smaller Diameter wheel: Going from 18 inch to 16 inch is a huge difference in required lean needed, with my setup and style especially braking is easier on a 16 inch wheel. 
• Lighter wheel: The less it weighs the more easily it is accelerated/braked also it uses less energy to propel it's own weight forwards/backwards 
• Soft/medium mode: It is literally assisted acceleration due to the programming of the modes forcing pedal dip to assist in moving the center of gravity forwards/backwards to achieve exaggerated results in a reduced timeframe. Personally as an approximately 85kg, 2 meter tall guy i feel too heavy/tall for soft mode as when i aggressively brake or accelerate, and i really power lean, i always feel the pedals dipping a little too much for comfort forcing an instinctive pullback from my part. I tried working it out for 400km but never got it to benefit my riding quite the opposite in fact. So i think how low one wants to go when it comes to soft/medium/hard mode should be somewhat based on weight/height. Ultimately it's personal choice, my only point is that weight/height affects how helpful/detrimental soft/medium/hard is.
• Leverage/Lever: Some kind of rod/lever/stick attached to the top one can push down on to force increased acceleration/braking. Presumably installed with some kind of forward leaning angle to make it disproportionally optimized for braking as i find that far more important. 
  Original idea: @conecones
• (Favorite) Pedals mounted on rails sliding horizontally: If pedal were mounted on rails and had the ability to slide themselves partially or (almost)all the way to the back/front of the EUC depending on soft/medium/hard. Or a separate soft/medium/hard/sliding turned off mode just for the rail system. No need for pressure sensors in the pedals for this idea. It is possible if a reliable way to slide the pedals incrementally on the rails is known.
  Pedals are attached to an internal metal rod like the one currently used in pedals only longer (maybe thicker?) and internally attached to reworked pedal hangers that would allow for horizontal movement of the pedal, and not allow for the rod to flex and bend. There are ways to water proof the horizontal opening in the side panels leading to the exposed rod that the pedals attach to when 3d designing the shell, exposing only the rod, needed for sliding, thereby waterproofing the "rail".
  Original idea: @conecones

Man the last idea really has my gears turning and i have really zeroed in on it. This could be quite revolutionary for EUCs. 

If the sliding was programmed to work incrementally like with the pedal dip of soft/medium only to equalize or rather re-center like the pedals do when no further aggressive acceleration/braking is detected, this could possibly be the single most powerful acceleration/braking assisting factor possible within the limits of physics. 

Someone more capable than me should pursue this innovation and i am very willing to explain my concept/design further, or hell i'll even attempt to illustrate it in ms paint if anyone is interested. 

Edited August 6, 2021 by xiiijojjo

[Planemo]

I think it's a really interesting idea, I really do. Like you say, treating pressure as a 'compliment' to pedal angle definitely sounds feasible in theory but I can't see it working in reality. I would love to be proved wrong though, I find the idea very interesting from a physics point of view alone

 

[null]

@xiiijojjo maybe if the moving pedals where on a curved rail (or equivalent) they could slide front / back with the foot pressure. (Just thinking out loud).

There are a lot of smart mechanisms to transform a motion into an other.

Edited August 7, 2021 by null

[mrelwood]

2 hours ago, null said:

 

@mrelwood I generally value your input but considering how you seem to think I don’t realise a EUC is a self balancing vehicle I find it fairly insulting to my intelligence. You take every point I make as if I where totally retarded and have no understanding of how a EUC or basic physics work. I won’t waste time replying further, think of it what you will.

I’m very sorry that you have decided to take my reply that way. I have absolutely no idea how well you understand physics, self-balancing vehicles, or pretty much anything at all. All I have to work with for a reply is your suggestion of a mechanism that would accelerate more than what’s required to keep the wheel upright.

If I understood the basic concept completely wrong, I’m terribly sorry, though a bit surprised that a person of your intellect lets mumblings of an unknown internet user to get under your skin deep enough to make you feel insulted.

2 hours ago, null said:

(edit: seeing how you spent a longer post to tell meepmeepmayer that a EUC with more torque didn’t accelerate faster (*with the same riding style (well duh)) I have to believe that you either take people for idiots or argue in bad faith.)

Well, he was under the assumption that it would. How do you suggest that one should respond to such assumptions?

2 hours ago, null said:

@all I don’t see any fundamental logical argument against my proposition

If your idea is as usable as you think it is, you really should have no problem answering any insulting posts as well, and refuting any points they have brought up.

2 hours ago, null said:

I truly don’t get that the concept of separating user input and EUC tilt as two separate data should so difficult to either grasp or imagine the use of.

Separating this from everything else written so far, generally if others don’t understand an idea in a single person’s mind, I can only think of two possible reasons: Either others don’t measure up to his level of understanding, or there is something fundamentally wrong with the idea.

 Can there be any other reasons?

[The Fat Unicyclist]

2 hours ago, null said:

@xiiijojjo maybe if the moving pedals where on a curved rail (or equivalent) they could slide front / back with the foot pressure. (Just thinking out loud).

There are a lot of smart mechanisms to transform a motion into an other.

Hmmnn...   

This is an interesting idea... Rather than making the wheel accelerate faster (in big joining in on that discussion), but using pedal pressure sensors to move the pedal forward/backward would increase the offset of the force applied by the rider. Much like moving your feet forward (or back) to achieve the same result - only more pronounced. 

Then again, pads have a similar effect...

But then, used together???   

[Planemo]

2 minutes ago, The Fat Unicyclist said:

Hmmnn...   

This is an interesting idea... Rather than making the wheel accelerate faster (in big joining in on that discussion), but using pedal pressure sensors to move the pedal forward/backward would increase the offset of the force applied by the rider. Much like moving your feet forward (or back) to achieve the same result - only more pronounced. 

Then again, pads have a similar effect...

But then, used together???   

I'm starting to doubt myself about this pressure-pad thing now

See, I totally agree that the above would work. In fact, I think we are all in agreement that ANY kind of mechanical leverage onto the wheel will work. Whether that be with power pads, sliding pedals or a vertical metal bar like a Segway.

So with that in mind, all the above are essentially converted into an electronic signal to the gyro. Thats all it is. So, arguably, a pressure sensor could 'tell' the gyro that the wheel is leaning further forward even though it isn't. This input would carry on until the rider reduced pressure on the front of the pedals.

Or am I losing my mind? 

[Silver]

4 hours ago, null said:

 

I truly don’t get that the concept of separating user input and EUC tilt as two separate data should so difficult to either grasp or imagine the use of.

Without some mechanical action that the wheel could take to shift the riders center of gravity forwards or backwards what good would that additional data be though? It still is limited by the need to stay balanced which is what me and I think @mrelwood are getting cought up on. It can know you want to go faster or that you are going up hill but what can it do about that without losing balance if you don't create more leverage or lean forward harder.

And some type of mechanical thing that shifted the center of gravity would add way to much complexity for my taste. I already don't like the sensor on my onewheel being a failure point I sure as hell wouldn't trust gotway to add something like that.

[xiiijojjo]

3 hours ago, null said:

@xiiijojjo maybe if the moving pedals where on a curved rail (or equivalent) they could slide front / back with the foot pressure. (Just thinking out loud).

There are a lot of smart mechanisms to transform a motion into an other.

With what i imagine i don't see how a curved rail could work, but to clarify. 

I'm not talking about having the pedal being able to freely slide around from side to side on the rail(it's a rod really) but rather i would need something mechanical on both sides of the rod that could use electricity to push the pedal back and forth on the rail, or have it more of less locked in the default position when non aggressive leaning, or if the user choose to disable sliding pedals, opting for a "normal" EUC experience, but still being able to activate it again. 

To put it simply it's kind of having a piston on each side of the rod that pushes the pedal around but always keeping it tight. If this was not part of the design it would feel like an exaggerated version of riding without the spacers on the normal pedal rod, allowing for that uncomfortable uncontrollable sliding of the pedals.

Edited August 7, 2021 by xiiijojjo

[mrelwood]

 

30 minutes ago, Planemo said:

So, arguably, a pressure sensor could 'tell' the gyro that the wheel is leaning further forward even though it isn't.

I don’t think the gyro can be involved in that way. Let it keep the pedals horizontal.

 What I think should work is a completely separate mechanism that only moves the pedals (or just the pedal plates) forward/backward. Same lean but standing more forward already equals more leverage for inclines. It can’t be fast enough to react to bumps though, as it would probably disturb the rider’s forward balance.

 Although, I don’t think pressure sensors would be needed for this. After all, the wheel already knows very precisely how much power it needs to apply to the motor to counteract the rider’s lean. Instead of pressure pads, I would simply use the already existing data from the gyro and the motor current to (calculate the rider’s lean and) move the pedals.

 Kind of like a horizontal soft mode instead of a rotary one… 

[xiiijojjo]

1 minute ago, mrelwood said:

 

I don’t think the gyro can be involved in that way. Let it keep the pedals horizontal.

 What I think should work is a completely separate mechanism that only moves the pedals (or just the pedal plates) forward/backward. Same lean but standing more forward already equals more leverage for inclines. It can’t be fast enough to react to bumps though, as it would probably disturb the rider’s forward balance.

 Although, I don’t think pressure sensors would be needed for this. After all, the wheel already knows very precisely how much power it needs to apply to the motor to counteract the rider’s lean. Instead of pressure pads, I would simply use the already existing data from the gyro and the motor current to (calculate the rider’s lean and) move the pedals.

 Kind of like a horizontal soft mode instead of a rotary one… 

YES someone is getting it !