Safety is a product feature

[OliverH]

I would call it a mandatory product feature. Compared to automotive (he we're also vehicles?!) in the EU szene it looks like the best high sophisticated things you'll see are renderings and exploded drawings for our EUs. I bet there's currently no development process in any structured kind. And safety for sure is not a big concern. It's not a centric product feature. 

To handle the safety requirements you need to know the risks. The automotive industry had derived their own standard from IEC 61508 (functional safety) as the ISO 26262 (road vehicles - functional safety) with ASIL categories and failure levels. With FMEA you can dive deeper on components, interfaces, etc to show risks and how to prevent them. And there're more methods like FTA doing risk assessments to have a proper view.

It's all about detecting errors or see errors rising and to react before a risk becomes an issue. I read this statement in a dissertation describing it in short words:

- a situation with hazard should be recognised (diagnose)

- after detection of the hazard there must be action to prevent an accident or reduce the heaviness of the accident (reaction)

In German we make differences between meanings of Sicherheit (Secure), Security and Safety. Mixing German and English words give us a more granular description:

Sicherheit (Secure) = secure against attacks (security) and secure operation (functional security => safety)

Regulations/ laws stating that vehicles must be conduct to public street in a secure operational (safety) way.

If you start with a development you need to shape you electric and electronic architecture (EEA) to fulfil the the safety requirements or to reduce complexity. 

Our EUs should always rely on this methodology to develop a safe and reliable product. Markets based on UN ECE regulations will need a basic analysis to prove the gov statement of redundancy and if in which components we really need it.

I'm not sure if the current manufacturers can handle this by own as they're small. The manufacturers should work together with a University on some fundamental base work (EEA, ISO 26262, FMEA, FTA and Markov) to develop their products on this findings.

To achieve this level we need a lot of time and may be some engagement from the western world.

Safety today is more like an accident (not build by design).

[johrhoj]

I agree wholehearteldly!

How do we get this message accross to EU manufacturers? How can we make them see that it is to their advantage?

On the one hand, people are willing to pay more for safety, on the other hand, more people wil ride EUC's when they are safe. Also safe EUC's are less likely to be banned!

Again, the central quenstion, how do we get this message accross?

[SlowMo]

For EU's to become safer. They need to be designed with 4 wheels and not only one. They should also have a protective casing like that of an automobile. 2 wheeled motorcycles are already hazardous on the road. More so with a single gyro powered wheel.

[OliverH]

The problem of the very low sales are safety at all, missing safety to start homologation where regulations are in place and missing safety to get a special permission where regulations are not in place.

There's a community in the German speaking countries and we founded in 2014 an association (eWheels.org - should be no advertisement). Target is to get the EUs street legal and to get EUs as a sport for the masses. We've invested some time to find solutions to get around the problem on a technical level, but no manufacturer we've spoken to showed interest on implementation. We're having in mind to build a prototype to show it to government. As the manufacturers haven't shown any interest we rely on the open source developments. This has the advantage to show the approval agencies/ government insides and to prove it works like intended.

To have the right base for talks we stepped back to start and working on analysis on the standards mentioned above. I've access to someone studied functional security (Safety) to prepare it. But this will need some time. 

Beside this we're working on a manufacturer certification program which should become public in 1-2 weeks. It will show gaps to the vision we have. It will show the same gaps on the competition with some slight differences. It's not the intention to do some face off. Intention is to show the direction to go to survive. And we offer help to fill the gaps for interested parties.

It's like playing a puzzle. We need to show the whole picture to get the understanding and the need for safety.

With the availability of technology to use other companies can appear, maybe not based in China. 

46 minutes ago, SlowMo said:

For EU's to become safer. They need to be designed with 4 wheels and not only one. They should also have a protective casing like that of an automobile. 2 wheeled motorcycles are already hazardous on the road. More so with a single gyro powered wheel.

No. Than we need to forbide bicycles and other common transportation vehicles  

We need to be classified right and we need to get permission on the right tracks/ pavements. We need to integrate us. In Switzerland we're classified as bicycles for the street rules. We're not allowed to ride on pavements which would be better when riding with pedestrian speed as riding on the street. This needs to be discussed with other lobby groups and government.

[Sonopanic]

EUC is too fast for a Walking people. So it is a logic consequence that an EUC is a bicycle in the eye of the law.

In german, i think more of : don´t wake the bear. Because, at the time the politican in Charge sees a 18" EUC

capable of 30km/h or faster, you will need a plate, you will need insurance and TÜV.

And then, any existing EUC with shutdown at overleaning will be put down, i´m shure of that.

But i agree, the electronics must be reworked, so the Wheel can protect itself without putting the driver in danger.

[OliverH]

21 minutes ago, Sonopanic said:

EUC is too fast for a Walking people. So it is a logic consequence that an EUC is a bicycle in the eye of the law.

In german, i think more of : don´t wake the bear. Because, at the time the politican in Charge sees a 18" EUC

capable of 30km/h or faster, you will need a plate, you will need insurance and TÜV.

And then, any existing EUC with shutdown at overleaning will be put down, i´m shure of that.

But i agree, the electronics must be reworked, so the Wheel can protect itself without putting the driver in danger.

We need this in Germany any way. It's likely integrated in MobHV. => type approval (Typenzulassung/ nationale Betriebserlaubnis) and insurance licence plate like a motorbicycle/ Mofa. That's 50-70 EUR to have insurance and ride it legal on street. And maybe 50-100 EUR on top for safety and approval with volume sales.

With type approval all non safety EUs will disappear. Not bad at all.

I've no problem with 18" and powerful motor but limited to 20 km/h.

If we ride with pedestrian speed on a pavement we can integrate us. But as there usually will every time an idiot driving slalom through pedestrians we're banned up in front - very logical and wise from this point of view.

[Sonopanic]

Problem there, the wheels we buy today will be banned.
So, i have to wait till there is a Regulation.

But i don´t want to wait. So, best Thing for me is, the authority leave me alone.

This works prefectly in my little town.

But this works with understanding for the other trafficmembers.
If i am an idiot, i can scare people with a bike or with inliners easy. Are there enough idiots, the politic
can´t ignore it and will regulate.

[OliverH]

Regulation will need some time as also products fulfil the requirements.

[Keith]

It can be useful to look also at how governments are reacting to drones as these are, in many ways a parallel development to EUCs (coincidentally with much of the same technology).

Already we have the US talking about licensing every drone, and the UK press gleefully reporting every air miss with them. You can reasonably bet that whatever reactive legislation that is put in place will similarly happen with EUCs as well especially if idiots riding dangerously get involved.

Ironically, the big problem with any technology and idiots is that modern technology is actually favouring the idiots in a way it never could in the past. For example, I've been flying model aircraft for more than 50 years, in all that time there has always been a steady stream of RITA's (Right Idiots Trying Aviation). Invariably they would turn up at a field with a totally inappropriate model (usually a Spitfire in the UK) take no advice whatsoever, demand their freedom to do whatever they liked and crash within 10 Metres of take off - never to be seen again. Drones require little skill and, as a result, the RITA's are keeping them in the air long enough to become truly dangerous.

Unfortunately no amount of legislation or licensing will actually help; it will just hurt the responsible users. The RITA's wouldn't know or care and, if they did, would consider it no more than an attack on personal freedom to be resisted at all costs.

Fortunately for all of us, EUCs are still seen as needing considerably more skill than is actually the case. That is tending to keep the RITEU's (Right Idiots Trying Electric Unicycles) away at the moment. However, if anything, they do tend to go for the Hoverboards which are perceived as easier to ride. There is a lot to be said for distancing EUCs from Hoverboards as much as possible!

Bottom line and short answer to this thread is that yes, we would all like to see an end to unpredictable shutdowns but don't forget that too much safety and too easy to use will bring the RITEUs along and, in the long term could do an awful lot of harm.

[THA]

@OliverH and others as well, I hope You consider a few points
1) EUC safety and performance usually conflict at least in some points: for example an EUC that starts tilt back early, like 15kph, with top speed of 25kph is a lot safer than EUC that hasn't any tilt back and top speed 20 kph
2) My current wheel is very safe on crashes, since it stops very fast when it falls down - this plays also abig role on safety to rider as well as others
3) It is perfectly safe to ride an EUC 25kph on bike lanes, and the same gadget You can mingle safe with pedestrians - just keep Your speed restrained.

Once, maybe just this time ever and never before at least, I'd say, follow finnish law. I'm suprised how they were actually able to make a law for these that really make sense! Note:we have alot of pavements allowed for bicycles too, not just pedestrians. When there is only on handful of pedestrians on sight, makes no danger to speed a little when no one close to You.

BTW: I think You can also fall down with Segway, if You lean forward too much -my daughter did that 1,5 years ago on family holiday.

[dmethvin]

12 hours ago, Sonopanic said:

In german, i think more of : don´t wake the bear. Because, at the time the politican in Charge sees a 18" EUC capable of 30km/h or faster, you will need a plate, you will need insurance and TÜV. And then, any existing EUC with shutdown at overleaning will be put down, i´m shure of that.

I think this is an important part about how we (the pioneer users of EUCs) view them. If your local government let an EUC use the sidewalk or bike lanes but limits them to 25kph or less, that should still be okay even if your particular EUC can go faster. In fact it's better because that gives you an extra margin of safety so you don't overlean it as long as you are not going too fast. We drive cars that are capable of 160kph or more but rarely go that fast in the city. Why should we expect to run at the max speed of an EUC all the time?

[Makoben]

The only simpler form of transporting a human being is a non electric unicycle. I think that in the years to come,  EU's will become a very common place means of transportation. Remember for years after the bicycle was invented, it had no brakes, people wanted to ban them. Technology came through and it is now one of the most efficient means of transportation for humans. Some people at the time bicycles were invented could see the potential and invented/evolved brakes, suspensions, seating, gearing and comfort. EU's are equal to the time when bicycles were just evolving. Bicycles started with a wooden frame and wheels, no seats and no brakes, and yes they were terrible. Bicycles also provided thrills and faster transportation, therefore people wanted to improve them. EU's have a long way to go when compared to bicycles(hundreds of years) and cars(a little over a hundred years). In the last century in the US there was a law that an automobile when approaching an intersection, had to have the driver go first into the intersection, ring a bell and fire off a shot before proceeding through the intersection. Now both car and bikes are fully accepted. The best way we can fit in the rest of the group is to get safer, easier, and here is the big one, increase our numbers. 

Topics like this post are how ideas are passed on and how as a group we improve our lot. Read through this forum and you will see many topics whose main goal is to improve our EU's. Forums members are the pioneers in this field and need to lead the rest. Every one may not be a mechanical, electrical or computer genius, but your opinions, your desires and your money is going to shape the future of EU's. Safety is a product feature and should be right on the same level as power, distance and looks if we are to succeed as a new means of transportation, and sport and just plain fun.

Mike

[OliverH]

10 hours ago, THA said:

@OliverH and others as well, I hope You consider a few points
1) EUC safety and performance usually conflict at least in some points: for example an EUC that starts tilt back early, like 15kph, with top speed of 25kph is a lot safer than EUC that hasn't any tilt back and top speed 20 kph
2) My current wheel is very safe on crashes, since it stops very fast when it falls down - this plays also abig role on safety to rider as well as others
3) It is perfectly safe to ride an EUC 25kph on bike lanes, and the same gadget You can mingle safe with pedestrians - just keep Your speed restrained.

Once, maybe just this time ever and never before at least, I'd say, follow finnish law. I'm suprised how they were actually able to make a law for these that really make sense! Note:we have alot of pavements allowed for bicycles too, not just pedestrians. When there is only on handful of pedestrians on sight, makes no danger to speed a little when no one close to You.

BTW: I think You can also fall down with Segway, if You lean forward too much -my daughter did that 1,5 years ago on family holiday.

To feel safe and have a safety reliable wheel is a different.

1) Totally agree. An EU needs as much power as possible to manage inclines and have enough balancing power

2).If I remember my starting time the issue that the wheel drives away only happens in the beginning. It never happened after the early hours/ days. And this point is a trade off between running stable (weight left/ right balanced), driving over steps without shutting off (also safety).

3) as higher the speeds as heavier can be injuries. We can be lift in an other area and need more features to prevent it.

The pavement is heavy discussed over here. Only kids on bicycles up to 8 years and disabled people with wheelchairs are allowed. There's a pedestrian lobby which is very strong.

8 hours ago, dmethvin said:

I think this is an important part about how we (the pioneer users of EUCs) view them. If your local government let an EUC use the sidewalk or bike lanes but limits them to 25kph or less, that should still be okay even if your particular EUC can go faster. In fact it's better because that gives you an extra margin of safety so you don't overlean it as long as you are not going too fast. We drive cars that are capable of 160kph or more but rarely go that fast in the city. Why should we expect to run at the max speed of an EUC all the time?

Don't mix up users

Sonopanic is from Germany. THA is from Finland.

An EU should handle a speed and needs a defined power still available for balancing. 

[OliverH]

4 hours ago, Makoben said:

The only simpler form of transporting a human being is a non electric unicycle. I think that in the years to come,  EU's will become a very common place means of transportation. Remember for years after the bicycle was invented, it had no brakes, people wanted to ban them. Technology came through and it is now one of the most efficient means of transportation for humans. Some people at the time bicycles were invented could see the potential and invented/evolved brakes, suspensions, seating, gearing and comfort. EU's are equal to the time when bicycles were just evolving. Bicycles started with a wooden frame and wheels, no seats and no brakes, and yes they were terrible. Bicycles also provided thrills and faster transportation, therefore people wanted to improve them. EU's have a long way to go when compared to bicycles(hundreds of years) and cars(a little over a hundred years). In the last century in the US there was a law that an automobile when approaching an intersection, had to have the driver go first into the intersection, ring a bell and fire off a shot before proceeding through the intersection. Now both car and bikes are fully accepted. The best way we can fit in the rest of the group is to get safer, easier, and here is the big one, increase our numbers. 

Topics like this post are how ideas are passed on and how as a group we improve our lot. Read through this forum and you will see many topics whose main goal is to improve our EU's. Forums members are the pioneers in this field and need to lead the rest. Every one may not be a mechanical, electrical or computer genius, but your opinions, your desires and your money is going to shape the future of EU's. Safety is a product feature and should be right on the same level as power, distance and looks if we are to succeed as a new means of transportation, and sport and just plain fun.

Mike

We don't need that much time like the cars and bicycles need to get that level:

-technology is there

-methods and standards are available to be used to reach the target

Just had yesterday a chat with a manufacturer. It's not easy to get the same frequency speaking with each other to understand together. I need to understand more how Chinese people think and how they see the markets. There's such a huge cultural difference.

If we just increase our numbers we just get more attraction by police (seizure, fine). That's what happens in some areas of Germany.

[Gimlet]

I think you are living on a fictional planet! Certainly not here on earth!

Point one: Standing on one self balancing wheel will never be 100% safe as no matter what built in safety you include things do go wrong. Without limitless power you will always get someone who is going to push the limits and try to go beyond the capabilities of the wheel.

Point two: Many people have shown from their comments that they are not happy to pay any significant premium for a "Safe" speed limited highly engineered wheel. Uniwheel being the case in point.

[dmethvin]

9 hours ago, Gimlet said:

Point one: Standing on one self balancing wheel will never be 100% safe as no matter what built in safety you include things do go wrong. Without limitless power you will always get someone who is going to push the limits and try to go beyond the capabilities of the wheel.

Point two: Many people have shown from their comments that they are not happy to pay any significant premium for a "Safe" speed limited highly engineered wheel. Uniwheel being the case in point.

There are two different types of failure here though, and I think it's important to separate the two.

First is operator-induced failure. It is nearly impossible to limit EUC speed. If it just refuses to increase speed to stay under you that is a recipe for a faceplant, but eventually you reach the torque limit. Tilt-back can help but has its own problems since insufficient torque situations can come up quickly without the wheel being able to warn you about it. EUCs could probably do a better job of giving feedback about their limits, and perhaps the weakest ones are just too dangerous to sell anymore.

Second is EUC hardware or software failure. The random Ninebot cutouts or bricking due to firmware issues are probably the best examples of that, but other models have their weak points too. 

Looking at cars, a combination of government mandates (seat belts, airbags) and insurance incentives have progressively reduced deaths significantly. If local traffic laws require EUCs to have lights or reflectors, travel at a safe speed, and for riders to wear safety equipment, that would go a long way towards reducing accidents and injuries related to operator-induced failures. For the second category of failure, I am pretty sure in the US that the Consumer Product Safety Commission (CPSC) has the ability to force a recall on products that are not working as designed, which could at least in theory be used to address problems like the Ninebot cutouts due to firmware defects. That would encourage vendors not to ship dangerous garbage products.

[THA]

11 hours ago, Gimlet said:

I think you are living on a fictional planet! Certainly not here on earth!

Point one: Standing on one self balancing wheel will never be 100% safe as no matter what built in safety you include things do go wrong. Without limitless power you will always get someone who is going to push the limits and try to go beyond the capabilities of the wheel.

Point two: Many people have shown from their comments that they are not happy to pay any significant premium for a "Safe" speed limited highly engineered wheel. Uniwheel being the case in point.

1) As won't be bicycles either - but as @dmethvin pointed out, some features shoud be more refined. Manufacturers could limit the top speed to 20kph even if the wheel is capable to run 30kph, by making it virtually impossible to push anymore at 20kph but still allowing comfortable cruising at like 18 kph. Okay, my opinion is that 25 kph is nice cruising speed, so limit shoud on that case be around 35kph. My wheel runs a little over 30kph max. but comfort limits to around 22-25 kph. From downhill (where tilt back doesn't border so much) to uphill I managed to faceplant probably due to exceeding my wheels electric motor/control circuit max. output limit

2) But what if those safe ones would be the only legal ones? I payed some extra for safety, because I'm the kind of person who is basically cautious but when excited, needs remainders and safety functions to prevent me to go too extreme. When I was younger... guess... But I don't care to pay any brand-related extra, so I rather pick up something else than 9b1, especially when rival brand offers better wheel in every aspect (including safety) on same price. If some brand lauches their wheel premium safety, I assume they'll just end up same as 9b1 at the moment: over-priced upper mid-range wheel.

Operator-induced failures will always be there, but manufacturers should too as much as they can to reduce opportunities, I agree. Then they could market their extreme-models for indoor, MX etc. use only (no street legal) - just like in Motocycle manufacturers (like Yamaha YZ vs. WR, XT, MT, YZF-R etc. and about all the big brands)

[Jurgen]

Safety = speed x safety gear x safety features

- Speed: Safety is very strongly related to speed (remember the kinetic energy equation), 0 KmH ~ 0 accidents (not taking meteorites into account), so it's seems common sense to me to use max cruising speed as cut-off: 8kmh (side walk, like a pedestrian), 25kmh (bicycle lane), > 25KmH (road), >90KmH (motorways)

- Safety gear: we've already had interessting debates here ('helmet the cool factor'), no point in starting all over again, but you could link it to the speed limit mentioned above (riding not faster than a pedestrian, maybe you can go without a helmet?)

- Safety features: for products that have another main objective than to be just safe (like airbags, condoms, etc.) this simply doesn't sell, Volvo almost went bust selling super safe shoebox like cars built like a tank. The consumer's reptilian part of the brain simply puts safety at the bottom of the wishlist.

Intellectually I'm interested in the safefy features Uniwheel is implementing. But somehow my reptilian brain already decided that it's too expensive for the other product features on offer.

[OliverH]

14 hours ago, Gimlet said:

I think you are living on a fictional planet! Certainly not here on earth!

Point one: Standing on one self balancing wheel will never be 100% safe as no matter what built in safety you include things do go wrong. Without limitless power you will always get someone who is going to push the limits and try to go beyond the capabilities of the wheel.

Point two: Many people have shown from their comments that they are not happy to pay any significant premium for a "Safe" speed limited highly engineered wheel. Uniwheel being the case in point.

I'm not living a daydream, not waiting that all comes good by self. I like to put the story on the desk. Follow this thread. The word safety is understood in different ways. I'm talking on safety as functional security, as described in standards.

It's about what is an acceptable risk. There are methods to analyse this and doing this will also raise up some test cases and behaviours (test case, detecting, action).  So we can deliver a bit more base stuff to get our EUs safer anyway.

We'll never eliminiate any risk. The question is what do we need to get in the area acceptable risk to get a major step ahead. Wait up till this is done, first in an easy/ general, abstract way, than it will get more detailed in further iterations. I'll show the big picture after doing some drawings and summary. 

2 hours ago, THA said:

1) As won't be bicycles either - but as @dmethvin pointed out, some features shoud be more refined. Manufacturers could limit the top speed to 20kph even if the wheel is capable to run 30kph, by making it virtually impossible to push anymore at 20kph but still allowing comfortable cruising at like 18 kph. Okay, my opinion is that 25 kph is nice cruising speed, so limit shoud on that case be around 35kph. My wheel runs a little over 30kph max. but comfort limits to around 22-25 kph. From downhill (where tilt back doesn't border so much) to uphill I managed to faceplant probably due to exceeding my wheels electric motor/control circuit max. output limit

2) But what if those safe ones would be the only legal ones? I payed some extra for safety, because I'm the kind of person who is basically cautious but when excited, needs remainders and safety functions to prevent me to go too extreme. When I was younger... guess... But I don't care to pay any brand-related extra, so I rather pick up something else than 9b1, especially when rival brand offers better wheel in every aspect (including safety) on same price. If some brand lauches their wheel premium safety, I assume they'll just end up same as 9b1 at the moment: over-priced upper mid-range wheel.

Operator-induced failures will always be there, but manufacturers should too as much as they can to reduce opportunities, I agree. Then they could market their extreme-models for indoor, MX etc. use only (no street legal) - just like in Motocycle manufacturers (like Yamaha YZ vs. WR, XT, MT, YZF-R etc. and about all the big brands)

The speed limit can be a configuration item defined by the distributor of the market. 

[dmethvin]

1 hour ago, OliverH said:

The speed limit can be a configuration item defined by the distributor of the market. 

When you say "speed limit" do you mean tilt-back or beeps? If you mean the rotational speed of the wheel you are asking for a faceplant.

[Mono]

2 hours ago, OliverH said:

We'll never eliminiate any risk. The question is what do we need to get in the area acceptable risk to get a major step ahead.

We obviously are already in the area of acceptable risk. My guess is that also under your criteria it is the case, as I assume you haven't stop EUCing, or have you? If you haven't, you have obviously decided the risk is acceptable. SCNR. 

I agree with the feeling that the status-quo with regards to safety does not reflect the current state of technology, while it should. Yet that is probably to be expected of a new and fast growing technology/market. And @Gimlet has a point that the talking is disconnected to the displayed behavior, as it often is. Regulation/certification would help to close down this gap though.

[SlowMo]

7 hours ago, OliverH said:

The speed limit can be a configuration item defined by the distributor of the market. 

Speed limits are just rules. Many will follow  but there are so much more adventurous  people who will not adhere to the rules and only ride within limits when they see the police. Face plants are very nasty. A normal helmet will not protect the face from having one and someone might end up with a face that only a mother could love. I created a new thread to show some examples:

 

 

[OliverH]

16 hours ago, dmethvin said:

When you say "speed limit" do you mean tilt-back or beeps? If you mean the rotational speed of the wheel you are asking for a faceplant.

Being a year forward or so/ a look into future: Some markets are regulated and we've national type approvals. There will be slight differences. Switzerland has 20 km/h max speed, Germany looks like to have the same, let's say France thinks 25 km/h is OK. Than we need to go through the Hazard and Risk Analysis. If it's still the same risk we need no other configuration in firmware and we need no hardware/ redundancy enhancement.  Than manufacturer x set the speed limit for products shipped to France with speed limit25 km/h to the French distri. A product shipped to Germany or Switzerland has a speed limit set by 20 km/h. It's set by the manufacturer and can only changed with tools from him. It's not allowed to have an easy protection bypassed by a customer by law. Markets without speed limit by law have the open speed/ competition version. A customer in France can also buy a competition version which is not valid to be driven on street with vehicle title and insurance licence plate.

A competition configuration has all the benefits of being tested totally different to today. It has much more behaviour handling in firmware integrated up to the speeds of e.g. 20/ 25 km/h. Above it still can no the break physics. But hopefully manufacturers learned from the testing that there need to been safety margins that riders don't tipp forward or that still high speed cut outs happens. A BMS should be designed for EU usage and not working as a bicycle BMS.

The speed limit itself is derived by the motor speed. And there can be audio or tilt back functions. 

14 hours ago, Niko said:

We obviously are already in the area of acceptable risk. My guess is that also under your criteria it is the case, as I assume you haven't stop EUCing, or have you? If you haven't, you have obviously decided the risk is acceptable. SCNR. 

I agree with the feeling that the status-quo with regards to safety does not reflect the current state of technology, while it should. Yet that is probably to be expected of a new and fast growing technology/market. And @Gimlet has a point that the talking is disconnected to the displayed behavior, as it often is. Regulation/certification would help to close down this gap though.

The definition of acceptable risk is the behaviour handling, how you manage to get from a fault to a stable state, how a non fixable fault is handled (lowering speed, limp home/ shut off),.. I'll expand the first thread above with some more explaining text and some drawings in the be t days.

 

12 hours ago, SlowMo said:

Speed limits are just rules. Many will follow  but there are so much more adventurous  people who will not adhere to the rules and only ride within limits when they see the police. Face plants are very nasty. A normal helmet will not protect the face from having one and someone might end up with a face that only a mother could love. I created a new thread to show some examples:

 

 

A face plant is the reason why we will have problems to show that we've in the area of acceptable risk. There will be probably one/ two step(s) in severity if looking on 15/20/25/30 km/h

[Guest]

I think electric unicycles will not be legal in countries like USA, Germany, France a.s.o. for the next ten years. It is more likely that they will be banned from the streets. Chinese manufacturers don’t give a shit, they just don’t care. The markets are to small (not enough demand from customers) for the manufacturers to be forced putting safety into these toys or to motivate reliable companies in the US, Japan or Europe to build safe EUCs. 

[SlowMo]

In Hongkong, all electric personal mobility devices are now banned from the streets and walkways. They are only allowed inside private premises.