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I thought I'd start a new thread for this topic for tidiness and leave the steering reversal thread separate as it's a very different approach at getting more speed.

Some of us would really like to increase the top speed of our MiniPros and I'm calling all technically inclined MiniPro riders to brainstorm ideas and hopefully work out a method.  Step one is going to be understanding how exactly the MiniPro detects the speed it's travelling at.  If we can trick it into thinking it's going more slowly than it is, we may be able to achieve a higher top speed.  We know it's not GPS related as it works independently of the software app.  We know it's not a physical limitation of the motors or motor controllers because in reverse it can happily do 25+kph.  So how exactly does it know how fast it's going?  Is it RPM related?  Is it related to the current/voltage supplied to the motors?    

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I'd guess it's RPM related as the current/voltage can vary widely with riders or different weights, and on different inclines. I agree, the best way to fix the problems with the mini pro is an alternative app of some kind. Just like the alternative apps of every other kind that let you do what you want. I can't do it. We need someone with serious software know-how to fall in complete love with their mini pro. 

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2 hours ago, kasenutty said:

I'd guess it's RPM related as the current/voltage can vary widely with riders or different weights, and on different inclines. I agree, the best way to fix the problems with the mini pro is an alternative app of some kind. Just like the alternative apps of every other kind that let you do what you want. I can't do it. We need someone with serious software know-how to fall in complete love with their mini pro. 

I don't think using an alternative app or editing the app will make a difference.  It's the firmware in the MiniPro itself that needs edited.  But there may be another way to do it if we can learn how the speed detection works.  If it's RPM then what components measure the rpm and can we mess with the signal they receive?  I wonder if some of the EUC experts understand how this works.  My Ninebot is extremely simple compared to the MiniPro.  It's just a brushless motor, a very small mainboard and a battery.  So the Ninebot might be a good place to start with figuring out how these machines detect the speed they are rotating the motors at.

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21 hours ago, esaj said:

I'm no expert, but I suspect without modifying the firmware, the only option would be to use larger tires. You do get a tradeoff between speed vs. torque though.

AFAIK, there is no separate measurement for the RPMs, but it's all tied to running the motor. At low speeds, the wheels seem to use the hall-sensors. If you go mucking about with their placement or such, the software cannot run the motor correctly, and cannot balance. At higher speeds, it seems that the wheels start to use a "sensorless mode" to estimate the position and the speed of the motor, that's built into the software itself. It could use something like back-EMF -voltage or current flow for input information, but again, if you go mess around with the measurements (like by changing the shunt measurement resistors, unless they're actually using current sensors), the end result is likely that the software cannot drive the motor correctly. And if they're not using sensorless detection, then they're likely still relying on the hall-sensors at higher speeds too.

Someone like @electric_vehicle_lover can probably shed more light into the issue, or maybe even knows a way around, these are just my personal conclusions based on (the little) that I know.

Esaj said everything. I would like to add that I did develop OpenSource firmware for EUCs that should also work for hoverboards as they share the same microcontroller. But this firmware don't have yet the code for the balance algorithm.

Anyway, I am going to an OpenSource path, like develop and OpenSource electronics and firmware, for building after an balance device and not develop for a specific product of a specific brand. I wish you good luck for such project to Segway brand.

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@esaj I think you are right. Other than larger tires, a hardware modification to increase speed is probably not possible. 

My next idea is to swap the motors over so that when riding in reverse at the higher speed, I would actually be standing on the device in the normal forward position, keeping the steering functioning normally. 

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This is actually possible because brushless motors are installed.
Normally it is sufficient to swap 2 of the 3 motor connections.
The engine additionally 3 sensor signals, whether that with this engine type goes I know not?

If the reversal of the direction of rotation is successful, however, the gyroscope sensor on the mainboard must be soldered and installed 180 degrees rotated.
I think this will be the biggest problem.

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20 hours ago, RooMiniPro said:

@esaj I think you are right. Other than larger tires, a hardware modification to increase speed is probably not possible. 

My next idea is to swap the motors over so that when riding in reverse at the higher speed, I would actually be standing on the device in the normal forward position, keeping the steering functioning normally. 

Correct me if I'm wrong about this for sure but if you simply swapped the motors over and stood on the Mini as per normal wouldn't leaning forward make you go backwards and leaning backwards make you go forwards and left is right and right is left? If you swapped the motors and stood on in reverse and leaned forward which is really backwards the Mini goes forward but the limits are in tact because the as far as the device is concerned you are still going forward. 

Swapping would not give the desired effect especially if what you end up with is a min that goes forward while thinking it is going backwards but you have to lean back to go ahead that would be seriously counter intuitive. 

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2 hours ago, Pezman said:

Correct me if I'm wrong about this for sure but if you simply swapped the motors over and stood on the Mini as per normal wouldn't leaning forward make you go backwards and leaning backwards make you go forwards and left is right and right is left? If you swapped the motors and stood on in reverse and leaned forward which is really backwards the Mini goes forward but the limits are in tact because the as far as the device is concerned you are still going forward. 

Swapping would not give the desired effect especially if what you end up with is a min that goes forward while thinking it is going backwards but you have to lean back to go ahead that would be seriously counter intuitive. 

Yeah if tilt is detected by gyro and not COG shift then it would not work. In the last posts at the link below I mention this. As Donald said, the gyro would have to be rotated 180 degrees along with the motor swap.

 

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Ok but if the gyro is turn 180 isn't the Mini Pro than essentially exactly the same as it was before you turned stuff around. Switch the motors around so forward is backwards and then the gyro so forward is backwards and then the whol thing -- hold on ok as I'm typing this is starting to click lol. 

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12 hours ago, Pezman said:

Ok but if the gyro is turn 180 isn't the Mini Pro than essentially exactly the same as it was before you turned stuff around. Switch the motors around so forward is backwards and then the gyro so forward is backwards and then the whol thing -- hold on ok as I'm typing this is starting to click lol. 

No because with the motors and gyro rotated you'd still be mounting and riding it in the forward position, making the feet position more natural and keeping the steering bar behind rather than in front.  It's hard for me to get my head around too, but ultimately I see it as a no-go.  I haven't looked at the gyro yet to see where it's located but it's probably surface mounted to a board, and there's no way I'm messing with the removal and re-soldering of that if so.

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On 27/05/2017 at 7:52 AM, RooMiniPro said:

We know it's not a physical limitation of the motors or motor controllers because in reverse it can happily do 25+kph.

A reasonable assumption, but not necessarily true.  They may have simply not envisaged someone going that fast backwards.

Remember that leaback and beeping are also affected by terrain surface and inclination and wind.  Whatever controls the speed must be detecting the load on the motors or the present drain on the batteries - nothing to do with anything as simple as RPM.  Therefore speed control is linked to device protection.  Try to get it to go faster than design speed may well mean forcing it into the zone where something may fail, or that battery protection might kick in leading to a sudden result.  Personally I think we have to accept that it is what it is, and that to try to change it requires a considerable amount of expertise which Segway have accumulated over many years.   But I realise I'm being an aged reactionary!

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And another thing... if someone comes up with a magic bullet to make the device go faster and posts it on the internet, they will certainly have a moral if not legal responsibility for what may follow - eg dumb users going too fast under inappropriate circumstances, or devices failing causing accidents.

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2 hours ago, Ozpeter said:

And another thing... if someone comes up with a magic bullet to make the device go faster and posts it on the internet, they will certainly have a moral if not legal responsibility for what may follow - eg dumb users going too fast under inappropriate circumstances, or devices failing causing accidents.

This is not true... 

Boba Motors has realised a 1300CV version of his Volkswagen Golf 5:D BUT not for that VW is responsible of this...:D

Many groups,  prepared cars and sell these modifications/tunings to normal people,  BUT, at last, only the final owners are responsible to have applied and used those modifications !!! ;) 

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I would like to find the gyro sensor.
It's probably on the mainboard.
Does anyone have high-resolution photos from the assembly page, so i can read the Ic label?

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Posted (edited)
12 hours ago, Ozpeter said:

A reasonable assumption, but not necessarily true.  They may have simply not envisaged someone going that fast backwards.

Remember that leaback and beeping are also affected by terrain surface and inclination and wind.  Whatever controls the speed must be detecting the load on the motors or the present drain on the batteries - nothing to do with anything as simple as RPM.  Therefore speed control is linked to device protection.  Try to get it to go faster than design speed may well mean forcing it into the zone where something may fail, or that battery protection might kick in leading to a sudden result.  Personally I think we have to accept that it is what it is, and that to try to change it requires a considerable amount of expertise which Segway have accumulated over many years.   But I realise I'm being an aged reactionary!

I agree with you on some points.  But the MiniPro is designed to carry a 220lb person at 17.5kph over bumps, inclines and declines, with enough power margin to remain balanced without risk of overload to the system.  It is safe to think that it can easily handle a 160lb person at a few kph faster.  Riding it in reverse proves that the speed limit is not a physical motor limitation, as I said.  It is pretty clear to me that the 17.5kph limit is there to keep the average rider safe.  It's not so fast that a loss of control would be likely to cause death or severe injuries.  And let's face it, the average rider is going to fall lower on the IQ scale and common sense scale than those of us who are technically minded and have the aptitude to modify systems like these.  Just reading the reviews on Amazon USA shows that about half of the buyers (or more) are borderline mentally disadvantaged.  Segway have to factor this in when setting speed limits.  Fat, stupid people with more money than sense will buy these, ride them at full speed over loose gravel or terrain they don't have the skills to handle, fall off, hurt themselves and then try to sue Segway for making unsafe products.     

Edited by RooMiniPro
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12 hours ago, Ozpeter said:

And another thing... if someone comes up with a magic bullet to make the device go faster and posts it on the internet, they will certainly have a moral if not legal responsibility for what may follow - eg dumb users going too fast under inappropriate circumstances, or devices failing causing accidents.

I strongly disagree with this.  Coming up with ideas for how to increase the performance of things does not carry a moral or legal responsibility for any harm that results from people attempting the modifications and hurting themselves.  We are just sharing ideas.  Civilisation is built purely on ideas.  If one of us figures out a way to make our MiniPros faster and we share the tutorial on a forum, it goes without saying that it's a 'do at your own' risk modification and it will obviously void your warranty.  Nothing is being sold and no one is claiming these mods are safe.  I built a portable fast charger for my EUC.  It may overheat one day and burn up.  It may damage my battery.  So far it's working perfectly.  But if someone else uses the info I shared and damages their property that's their own responsibility. 

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1 hour ago, RooMiniPro said:

 

I strongly disagree with this.  Coming up with ideas for how to increase the performance of things does not carry a moral or legal responsibility for any harm that results from people attempting the modifications and hurting themselves.  We are just sharing ideas.  Civilisation is built purely on ideas.  If one of us figures out a way to make our MiniPros faster and we share the tutorial on a forum, it goes without saying that it's a 'do at your own' risk modification and it will obviously void your warranty.  Nothing is being sold and no one is claiming these mods are safe.  I built a portable fast charger for my EUC.  It may overheat one day and burn up.  It may damage my battery.  So far it's working perfectly.  But if someone else uses the info I shared and damages their property that's their own responsibility. 

Completely agree B)

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2 hours ago, RooMiniPro said:

...  It is pretty clear to me that the 17.5kph limit is there to keep the average rider safe.It's not so fast that a loss of control would be likely to cause death or severe injuries.  

...

Just reading the reviews on Amazon USA shows that about half of the buyers (or more) are borderline mentally disadvantaged.  Segway have to factor this in when setting speed limits.  Fat, stupid people with more money than sense will buy these, ride them at full speed over loose gravel or terrain they don't have the skills to handle, fall off, hurt themselves and then try to sue Segway for making unsafe products.     

That's right.

AFAIK, MiniPro's went faster in their early days, right before Ninebot has bought Segway. And once they got UL-sertification (and/or because of that) they have made the unit more safe, even excessively at that... Probably to avoid unnecessary and ridiculous lawsuits. (Alas, they have aquired Segway to put an end to copyright feud with them.)

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I bet a Gotway or Kingsong Minipro would be way more fun. 

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52 minutes ago, Vik's said:

That's right.

AFAIK, MiniPro's went faster in their early days, right before Ninebot has bought Segway. And once they got UL-sertification (and/or because of that) they have made the unit more safe, even excessively at that... Probably to avoid unnecessary and ridiculous lawsuits. (Alas, they have aquired Segway to put an end to copyright feud with them.)

You're right. ..

For those reasons I think that Ninebot will never produce or setup a unit with more speed...:(

This is the reason why All we need is HACK:D :clap3::whistling:

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Posted (edited)
46 minutes ago, kasenutty said:

I bet a Gotway or Kingsong Minipro would be way more fun. 

Surely ;)

Unluckily,  they will never earn the possibility to got the license to be rode officially on roads, bike tracks and sidewalks. ...:rolleyes:

Edited by zugu

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16 minutes ago, kasenutty said:

What's a license? :D

:D

Jokes apart. ..here in Italy, and precisely in Trento,  was just applied a heavy sanction of 1200 Euro and the device was sequestered by the Police for a guy with an hoverboard that on a sidewalk pushed a pram...:facepalm:

Anyway. .. here the trend is to sanctioning .....:furious:  so, licence will become the only mean to ride without pain...:blink: 

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