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1 hour ago, houseofjob said:

So the "double redundancy" claimed on the new Ninebot One Z marketing points also exists on the current Gotway Tesla and GT16 (reportedly 4x redundancy), as shown below:

 

 

I just have looked into this now....

Good joke! Then my 1680wh Ks18s has 8time redundancy....hahaha.

I guess that is not that we exspect from real redundancy. I understand that in case of a mosfet/board/resistor fail something jumpes in.

 

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  • 2 weeks later...

Nothing which deals with the upcoming Personal Light Electric Vehicle (PLEV) Standard from CEN named EN 17128, we need real redundancy and we’ll see a bright future for EUCs or it will keep low volume (and will get much lower) as a sport utility not for road use.

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19 hours ago, OliverH said:

Nothing which deals with the upcoming Personal Light Electric Vehicle (PLEV) Standard from CEN named EN 17128, we need real redundancy and we’ll see a bright future for EUCs or it will keep low volume (and will get much lower) as a sport utility not for road use.

Publication of the standard is planned in May 2019, why would EUC makers care yet?

Adoption by EU members probably won’t be before 2020, a very long shot for Gotway and Kingsong that are mostly startup size...

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  • 2 weeks later...

The standard should now ready for end of 2018 (+vote/publishing Periode). The current prEN 17128 was rejected by two countries because not having the right layer. There will be heavy work in the next months. Next meeting in Brussel (7-9.11) will be a hard discussion.

If PLEV is in place it‘s the base to get EUC legal on street, if compatible and certified to PLEV. What does it mean:

  • Being compatible to PLEV, all test passed
  • having a safety concepts with all reliability calculations 
  • being certified against PLEV and machine Directive => real CE (not some subset like today)
  • sell EUCs based on the certification, having quality control in place

The current EUC manufacturer don‘t need to care about PLEV. Without any help they‘ll not able to get certification. They’ll fit in the category sport vehicle not being street legal. There will be new manufacturer to deliver PLEV EUCs.

as a serious manufacturer I would develop the technic now. That will be a long process to have the right level for certification. The people doing it need to have the maturity finish the job. I only have two companies in mind having the knowledge: InMotion and Segway. But it’s a guess only.

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15 minutes ago, OliverH said:

Germany and Norway ;)

I'm very surprised Germany rejected that standard as I thought they were letting anything into their country no matter how dangerous or damaging.

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28 minutes ago, LanghamP said:

I'm very surprised Germany rejected that standard as I thought they were letting anything into their country no matter how dangerous or damaging.

Where did you hear that sentence? The safety of machinery is valid for all products. A CE label states that a device complies to the safety of machinery. Looking on EUC they fullfill two small chapters of safety of machinery. The CE certification of todays EUC are not worth anything and the CE labeling is not allowed in this context.

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AFAIK, the only self balancing vehicle with redundancy is the Segway, which has two controller boards.  If one fails for some reason, the other board keeps the device from cutting off, but slows the speed and forces you to send it in for service.  The batteries I am not remembering about, except they are very expensive to replace.

 

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It‘s not only being redundant, it‘s the concept and risk analysis resulting in a safety concept to get a safe device. This is an easy written sentence not showing the complexity and work behind that.

Product Safety laws in Europe request conformity to safety of machinery (2006/42/EC) and corresponding harmonised standards. It‘s a hard way to get a conform EUC. 

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One of the problems with redundancy in a EUC is the small size. Not only do we need a second board, but also the cooling, wiring and probably some circuit that controls which of the boards that carries the load - unless we want them in passive parallel, with the consequent risk of an electrical spike from one card killing the other.

OTOH, just looking at my GT16, i can actually imagine a way of using the same heat-sink for two cards placed vertically.

It would probably mean the cards would need to have a slightly different design, but that shouldn't be a big problem. On the upside, the current idea of air-ducts could be expanded with a more comprehensive - computer-style - heat-sink where the card now resides, and larger air-ducts to lead air over the cooling fins...

Suppose you had the boards in parallel, but had some form of spike-protection between them, or even let each card be served by the two battery-packs on that side. Leaving only the motor connection and the charging wires as the common connection...

Of course it's a question of cost, but I really doubt that is a great problem considering the cost of batteries, shell and motor. It may up the final cost by a couple of hundred dollars.

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9 hours ago, OliverH said:

It‘s not only being redundant, it‘s the concept and risk analysis resulting in a safety concept to get a safe device. This is an easy written sentence not showing the complexity and work behind that.

Product Safety laws in Europe request conformity to safety of machinery (2006/42/EC) and corresponding harmonised standards. It‘s a hard way to get a conform EUC. 

I noticed prEN 17128:2017 costs 182,60 EUR for download at https://www.beuth.de/de/norm-entwurf/din-en-17128/271084773

Is that good democratic manners, to restrict the discussion to paying patrons? I don't think so :furious:!

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9 hours ago, Scatcat said:

One of the problems with redundancy in a EUC is the small size. Not only do we need a second board, but also the cooling, wiring and probably some circuit that controls which of the boards that carries the load - unless we want them in passive parallel, with the consequent risk of an electrical spike from one card killing the other.

OTOH, just looking at my GT16, i can actually imagine a way of using the same heat-sink for two cards placed vertically.

It would probably mean the cards would need to have a slightly different design, but that shouldn't be a big problem. On the upside, the current idea of air-ducts could be expanded with a more comprehensive - computer-style - heat-sink where the card now resides, and larger air-ducts to lead air over the cooling fins...

Suppose you had the boards in parallel, but had some form of spike-protection between them, or even let each card be served by the two battery-packs on that side. Leaving only the motor connection and the charging wires as the common connection...

Of course it's a question of cost, but I really doubt that is a great problem considering the cost of batteries, shell and motor. It may up the final cost by a couple of hundred dollars.

No need for good cooling or any at all for the bacup electronics. As long as it is able to maintain the balance at the current speed that it fails at it will be good enought.
Then have it sound the alarm in a way that gets the attention of the rider so he steps off.  Just what i think would be enought xD 

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1 hour ago, RenaissanceMan said:

I noticed prEN 17128:2017 costs 182,60 EUR for download at https://www.beuth.de/de/norm-entwurf/din-en-17128/271084773

Is that good democratic manners, to restrict the discussion to paying patrons? I don't think so :furious:!

We pay over 1000 EUR per year being part of the German mirror board at DIN. 

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2 hours ago, em1barns said:

@OliverH, could you explain how EUCs will be able to implement the hard speed limitations required in PLEV?

 

I don‘t understand your question. Early Gotways like my MSuper V2 had no speed limitation. Reaching the maximum design speed they did a power cut. Today’s EUC have a speed limit and don‘t do a power cut. Maximum speed will be tested on flat ground. I insiste€ in the call from October to have a over speed margin for downhill cases, to have the chance for controlled speed reduction without power cut.

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1 hour ago, RenaissanceMan said:

I noticed prEN 17128:2017 costs 182,60 EUR for download at https://www.beuth.de/de/norm-entwurf/din-en-17128/271084773

Is that good democratic manners, to restrict the discussion to paying patrons? I don't think so :furious:!

This version made a step back from the September 2016 version we made in the international meeting in Paris. I‘ve no idea why the paper made a step back with the prEN 17128.

Backup info on the standardisation process: http://www.ewheels.org/news/681/develop-european-standard-en

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10 hours ago, Scatcat said:

One of the problems with redundancy in a EUC is the small size. Not only do we need a second board, but also the cooling, wiring and probably some circuit that controls which of the boards that carries the load - unless we want them in passive parallel, with the consequent risk of an electrical spike from one card killing the other.

OTOH, just looking at my GT16, i can actually imagine a way of using the same heat-sink for two cards placed vertically.

It would probably mean the cards would need to have a slightly different design, but that shouldn't be a big problem. On the upside, the current idea of air-ducts could be expanded with a more comprehensive - computer-style - heat-sink where the card now resides, and larger air-ducts to lead air over the cooling fins...

Suppose you had the boards in parallel, but had some form of spike-protection between them, or even let each card be served by the two battery-packs on that side. Leaving only the motor connection and the charging wires as the common connection...

Of course it's a question of cost, but I really doubt that is a great problem considering the cost of batteries, shell and motor. It may up the final cost by a couple of hundred dollars.

An inherent safe design could be made with redundant boards or with a board with necessary redundant features based on a risk analysis. But a complex board like today will be replaced with different boards/ splitted functionality. My crystal ball shows: COTS parts (not from EUC manufacturers) will be used in any case possible.

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17 hours ago, OliverH said:

I don‘t understand your question. Early Gotways like my MSuper V2 had no speed limitation. Reaching the maximum design speed they did a power cut. Today’s EUC have a speed limit and don‘t do a power cut. Maximum speed will be tested on flat ground. I insiste€ in the call from October to have a over speed margin for downhill cases, to have the chance for controlled speed reduction without power cut.

Today’s EUC don’t have a hard speed limit, the only limit is still the cutout limit...

Today’s EUC have speed warnings, with tilt back and/or beeps. Nothing prevents to accelerate beyond tilt back or when there are beeps.

Is tilt back defined as an acceptable speed limit in PLEV? If so, what angle would be reasonable without putting the driver at risk?

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1 hour ago, em1barns said:

Today’s EUC don’t have a hard speed limit, the only limit is still the cutout limit...

Today’s EUC have speed warnings, with tilt back and/or beeps. Nothing prevents to accelerate beyond tilt back or when there are beeps.

Is tilt back defined as an acceptable speed limit in PLEV? If so, what angle would be reasonable without putting the driver at risk?

Defined is a Speed limit on a flat surface. Tilt back is defined as signalisation. PLEV should be a general regulation and the manufacturer should be allowed to take action he thinks to fulfil the requirement. Current design/ architecture will not be suitable to pass certification. It's not just a software/ config modification.

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19 minutes ago, OliverH said:

Defined is a Speed limit on a flat surface. Tilt back is defined as signalisation. PLEV should be a general regulation and the manufacturer should be allowed to take action he thinks to fulfil the requirement. Current design/ architecture will not be suitable to pass certification. It's not just a software/ config modification.

That’s what I fear. I read the PLEV proposal, and it does not feel like it has taken EUCs into account.

My understanding is that EUCs cannot brake to prevent accelerating beyond 25km/h. Braking would ensure face plant.

So looks like PLEV will be death for EUCs in Europe...

 

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25 minutes ago, em1barns said:

That’s what I fear. I read the PLEV proposal, and it does not feel like it has taken EUCs into account.

My understanding is that EUCs cannot brake to prevent accelerating beyond 25km/h. Braking would ensure face plant.

So looks like PLEV will be death for EUCs in Europe...

 

We had a really great discussion last Sep in Paris and added quite a lot stuff. In the prEN 17128 all this content disappeared. We’ll have a nice discussion in one and a half week in Brussels on the CEN meeting.

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