Suggestions For Safety improvements

[Slick]

When the Tiger's tail slips out of your hand!

I have a design improvement suggestion, I hope that the Manufactures/designers/RD read this.

I love my new Gotway MSuper!  I had a mishap yesterday that could have been disastrous.  I started to pull the trolly handle out my never wrecked MSuper, when it slipped out and my hand about half extended, the unicycle flipped out.  The unicycle acted like an 84 volt 53 lb toy top, accelerating completely out of control, out of balance and out of whack, jumping wildly about 4 to 5 feet into the air.  It totaled the handle.  Scratched up the EUC.  Oh well, now I can stop worrying about having a wreck and scratching it up.  The whole event only lasted a few seconds, but it was very intimidating.  I think that there may be a need for a safety design update.  In aviation there is a switch called a “squat switch”.  On the landing gear of an airplane when the plane is on the ground the squat switch prevents the landing gear from retracting.  In theory a person could flip the handle to raise the gear, and after the plane’s weight was off of the landing gear the gear would raise.  The squat switch prevents the landing gear from retracting or just folding up while the plane is on the ground and someone accidentally flipped the landing gear switch.  On an EUC the “squat switches” or safety switches would be on the pedals and handles and when pressure is off both the pedals and handles including the trolly handle the EUC would just fall on its side harmlessly.  It would also help minimize damage to EUC when a person would have to jump ship in the event of losing balance, or when the handle just slips of your hand.  We have all seen our EUC do that dance, you know that wild top, and we have also seen them just continue rolling without us on board, while we run behind with that sinking feeling hoping it doesn’t hit a car, person, lake…..  It is just a thought.

[Gimlet]

Not really sure how this could be accomplished? If you have it switching off the power then the trolley handle isn't a lot of use as the wheel is too heavy to use the handle when powered off.

[ir_fuel]

2 hours ago, Slick said:

On an EUC the “squat switches” or safety switches would be on the pedals and handles and when pressure is off both the pedals and handles including the trolly handle the EUC would just fall on its side harmlessly.  It would also help minimize damage to EUC when a person would have to jump ship in the event of losing balance, or when the handle just slips of your hand.  We have all seen our EUC do that dance, you know that wild top, and we have also seen them just continue rolling without us on board, while we run behind with that sinking feeling hoping it doesn’t hit a car, person, lake…..  It is just a thought.

Let's not.

I don't want to hop off/on a curb, or ride over some obstacle whereby I lose contact with the pedals for a fraction of a second and the device decides to shut off because of that.

[xebeche]

@Slick it's not entirely clear from your description of the event, but it could be that you had what is called "wild spin" and is a known "feature" of Gotway wheels - meaning that they don't turn into a dead animal after they lean beyond certain unrideable angle as they should (and as most wheels from other manufacturers do), but instead they do this:

 

 

[Mono]

On 24/09/2017 at 6:11 PM, Gimlet said:

Not really sure how this could be accomplished? If you have it switching off the power then the trolley handle isn't a lot of use as the wheel is too heavy to use the handle when powered off.

I am lately trolleying my wheel more often off than on. Even with the kill switch on the V8, I still don't like to bow down to carry it over stairs. So I just trolley it off and use the trolley handle to go up and down stairs having a little arm exercise en passant. Trolleying like this needs a little more skills, but it works well for the usual paths (like in and out of the train and through the station) and is much better than carrying. 

Technically, one could limit the torque above trolling speed (not sure if this is the best option). One can limit the speed to the current speed when no weight or no mass close to the pedals is detected and switch to super soft mode. I have a hard time to believe that it is not possible to figure something out that is technically feasible. Didn't Uniwheel have something like this?

[Gimlet]

Uniwheel had very clever foot or leg sensors, not sure which but if both feet were off the wheel it shut down.

It also shut down automatically when lifted by the handle, very useful for stairs.

No trolley option though, but it was a lightweight wheel.

[Keith]

8 minutes ago, Gimlet said:

Uniwheel had very clever foot or leg sensors, not sure which but if both feet were off the wheel it shut down.

It also shut down automatically when lifted by the handle, very useful for stairs.

No trolley option though, but it was a lightweight wheel.

The Uniwheel sensors looked sideways from the casing so I think they sensed the legs. However: If both legs were off the wheel and it was not moving fast it shut down. This did mean that you could step off, pick it up, walk up stairs, put it down, step on and go. It did not shut down, like an Inmotion V8, when you lifted the handle, it shut down because your feet were not on it.

Whether it would have cut out if you fell off at speed and the wheel remained upright has never, to the best of my knowledge, been demonstrated. There is a fine line between cutting out in a fall and cutting out whilst getting air riding over (say) a jump. I wonder if that was one of the problems they didn't solve?

[Demargon]

Hello @Slick. Maybe the solution are the safety strap to hold the euc when you fall, using it always (maybe attached to your belt) prevent also any accident like yours. 

The next step is a switch off for that strap. Even better with a setup of airbags, stabilization legs or a emergency brake device. I have some ideas to accomplish that but most fails in the basic premise of a simplicity witch define the euc.

Pd: I don't want a pedal lift switch. One in the handle is enough (like Im. v5 and v8)

[Mono]

On 26/09/2017 at 12:36 AM, Keith said:

Whether it would have cut out if you fell off at speed and the wheel remained upright has never, to the best of my knowledge, been demonstrated. There is a fine line between cutting out in a fall and cutting out whilst getting air riding over (say) a jump. I wonder if that was one of the problems they didn't solve?

It seems to be a good idea to make a distinction between "cutting out" and "not applying torque under well specified conditions" or even "not increasing wheel spinning speed under well specified conditions".

[Snurre]

On 9/24/2017 at 5:43 PM, Slick said:

[...] when pressure is off both the pedals and handles including the trolly handle the EUC would just fall on its side harmlessly. [...]

It's a nice thought although any solution that will cut the power at speed is also subject to possible failures and that would scare me to death...

(I also think Alex Segmüller would strongly oppose: )

 

[tudordewolf]

I think part of the challenge of preventing "wild spin" is that centripetal forces are going to affect the unicycle's perspective of "down" - if it's supposed to go dead at 45 degrees of tilt but the unicycle is spinning itself in a tight circle, it is going to experience g-forces that make it think it's still mostly upright. 

[LanghamP]

MSuper V3s is just plain dangerous when trolleyed or laid on its side. I roll it by its handle most of the time, and I think Kingsong had the right idea of simply not including in internal trolley for their KS18.

You can't call yourself an EUC rider until you've had an EUC do a 180 degree spin around your mounted foot, then crawl up your leg to your chest, then proceed to kick the everliving shit out of you while exclaiming in a female voice, "danger danger!"

Twice.