xiiijojjo Posted May 1, 2017 Share Posted May 1, 2017 10 hours ago, Hunka Hunka Burning Love said: I get the feeling that xiijojji (geez couldn't you have ppiccked an easier username to type? ) is pretty young and fearless. Anyways, don't take our reactions the wrong way. We do welcome you to the forums, and thank you for sharing your experience with us. Well a couple of days ago i thought i was immortal but i'm sure that crash added a lifetime of wisdom. I understand the reactions guys but there's a reason i didn't make a tread for this story and it's because i wanted to use it specifically to disincentivize OP from going down the road i just ate xD Because what he was talking about is pretty much the same stuff that led to my crash. But thanks for the welcome i know it's not the best way to join but now i can use my knowledge to help others hopefully. 3 hours ago, Rehab1 said: We, the forum members, are striving to advance our cause that will allow us to commingle with pedestrians on roads, parks, sidewalks, etc. without the public fearing for their lives! When it comes to public perception i have been careful and displayed control. I didn't even bring my original unicycle to the public before i could mount it with no support etc. Because i like many forum members realize that i am a representative of a new technology where my actions can end up having an impact on legislation in my country. Oh and just to make it absolutely clear: MY ACTIONS ON THE DAY OF MY CRASH WERE ABSOLUTELY STUPID. MY MOTIVATION WAS STUPID. MY LACK OF PROTECTIVE GEAR WAS STUPID. i get i i get it i get it i get it i get it...i get it Link to comment Share on other sites More sharing options...
Hunka Hunka Burning Love Posted May 1, 2017 Share Posted May 1, 2017 I don't think your motivation was stupid. It's basic curiosity to want to see how fast these wheels can go, and you would naturally think they would design them to protect the rider at their limits. Unfortunately the wheel's capability to prevent failure is not always possible at this time. It's the Achilles heel of these devices that sometimes they just cut out if you ignore the warnings (if it even gives you any). If you have a need for speed, there are safer alternatives to get that thrill from. I don't think they originally designed these wheels to ever go that fast. There's just no safety net when you are rolling on one wheel except beeps and tiltbacks (which can be unsettling at high speed depending on their rate of tilt). The lack of protective gear... well, to each their own. Some still don't wear it so it's a personal choice, but to test the limits of a wheel without it is probably questionable. Here's some videos to watch: Riding in swim trunk protective shorts at the limit (there's also part 2 and 3 if you look for them): Link to comment Share on other sites More sharing options...
xiiijojjo Posted May 1, 2017 Share Posted May 1, 2017 Well for me the 80% beep has become my speed limit and honestly since the crash i've only heard that beep once It's a strange design to protect the batteries rather than the rider... But from a design point of view what could you even do to add more safety at high speeds?? Add a last alarm that constantly blares out a high pitch noice at 90%? I mean even THAT people would push beyond. I don't think making built-in tilt back at certain factory set speeds is the way either. I guess they've done what they can in regards to alarms... The only thing i could criticize might be how these companies advertise speeds. I think they should only be able to advertise the top speed of say an 80kg rider at 80% battery draw formatted as such (for instance) : "Top speed 34km/h for a 100kg rider" "Top speed 37km/h for an 80kg rider" "Top speed 40km/h for a 60kg rider" (did not do the math it's just an example) So that first of all the consumer gets the idea of a static speed limit out of their head and so that the consumer can more easily have an idea about the approximate speed limit in regards to themselves - this way your advertised speed limit would be "safe" in the sense that your unit is only drawing 80% power at the advertised speed. The companies themselves would then of course have to emphasize several places and in great detail just how important respecting that 80% power draw warning is and how instead of a "80% power draw warning" it should be perceived as " you have now hit the speed limit of this device please slow down until you don't hear the warning anymore" but i don't really think any of the companies would adopt any of these changes and also this would not stop a few idiots like myself to find "the true limit" in otherwords "the faceplant factor" of these devices edit: maybe even changing out the 80% beeps with a voice saying "speed limit exceeded, slow down" repeating until you are below 80% would help slightly? Link to comment Share on other sites More sharing options...
Hunka Hunka Burning Love Posted May 1, 2017 Share Posted May 1, 2017 That's a very smart point to make. I think I made the exact same statement many moons ago. Over time I believe that it has been determined that often manufacturers will use the weight of an average young Asian person (140 lbs or about 60 kg) as their test reference when stating "maximum" speeds. Even then that doesn't take into account battery condition (age or charge), ambient temperature, headwind, road grade, tire inflation psi, acceleration rate, etc.. I've always thought of it as a multi-factored equation which is difficult to calculate as some factors vary constantly. For example accelerating at a very high rate versus accelerating slowly up to a fast speed likely have different draws on the battery. Zooming fast up to maximum speed before failure may not allow the wheel to have any extra power to tiltback or warn you in time. If there was a motor able to move 400 pounds at any acceleration and up to 100 KPH while climbing a 45% incline with a 40 KPH headwind at 5% battery charge, now that would be over-engineering for safety as it would be difficult to exceed the motor's abilities. I'm exaggerating of course, but I think you get my point. That motor does not exist yet and might never so we have to be mindful of these stated "limits" for our own safety with what we have to work with today. Link to comment Share on other sites More sharing options...
Rehab1 Posted May 1, 2017 Share Posted May 1, 2017 48 minutes ago, xiiijojjo said: It's a strange design to protect the batteries rather than the rider... 13 minutes ago, Hunka Hunka Burning Love said: That's a very smart point t I never thought of it that way either! Interesting! So should we all start praying to the Battery Gods which in turn will protect the riders? Link to comment Share on other sites More sharing options...
Carlos E Rodriguez Posted May 1, 2017 Share Posted May 1, 2017 18 minutes ago, Rehab1 said: I never thought of it that way either! Interesting! So should we all start praying to the Battery Gods which in turn will protect the riders? It all very silly. I know the issue. they are just too lazy to upgrade the design to fix these limitations. The limitations and how the went about is just bad engineering. Its like the old cars. Originally they did not have rev limiters. You could get going in first gear and just floored and the engine would just blow up. But people learned to know how cars worked. eventually they put the rev limiters so you would not destroy your car or claim your car has a quality issue so they would fix it for free. So what need to be: - MOSFET: There is not reason for the MOS chip to blow up. The circuit and software need to updated so the operating conditions are not exceeded and that would require additional components on the board. -OVER SPEED CUTOFF: There is not need for that either. The computer is fully aware of how much battery is left. The circuit and software need to monitor, voltage, current and Back-EMF and soften the balance power to not exceed the operations limits of the available volts, amps and Back-EMF. -OVER CURRENT CUTOFF: There is no need for that either. The software and circuit need to be updated so that when reaching the limit of amps available, the computer just wont give more than the max. This obviously will give the pedals a soft pedal but at least you wont get dump like a bad date. -BMS CUTOFF: The computer should not let that happen either. That function should only be triggered during a system failure to prevent battery overheating and a fire. So computer need to update the software to prevent the condition. This is not difficult. I just don't think they want to do it because it will cost engineering dollars. The Brand that implements this first and keeps a high performance will dominate. Imagine a wheel that as you approach the limits it will warn and the if approaching the limit it will just get soft but return to normal if you slow down ( no cutoff). Then you ride it up any grade with no cutoff just alarms and softness. Then they do a demo trial showing how all the other wheels dump you of get fried. That would be the market winner. Link to comment Share on other sites More sharing options...
xiiijojjo Posted May 1, 2017 Share Posted May 1, 2017 3 minutes ago, Carlos E Rodriguez said: Imagine a wheel that as you approach the limits it will warn and the if approaching the limit it will just get soft but return to normal if you slow down ( no cutoff). Then you ride it up any grade with no cutoff just alarms and softness. What do you mean by "softness" and " it will get soft " ? I understand you are referring to a kind of safe way to do the speed limiting but i don't quite understand what you mean by the wheel going soft. Link to comment Share on other sites More sharing options...
Carlos E Rodriguez Posted May 1, 2017 Share Posted May 1, 2017 6 minutes ago, xiiijojjo said: What do you mean by "softness" and " it will get soft " ? I understand you are referring to a kind of safe way to do the speed limiting but i don't quite understand what you mean by the wheel going soft. ok. When the computer is in full control it gives and takes power based of the magnitude of the angle away from center. That make the pedals firm and steady and almost flat as you ride. When you approach the limits, the computer should be aware of that and not output more power but keep the maximum it can give. If the software does that, then the pedal will go soft and start tipping say forward because it is not putting higher power to keep the pedals balanced and flat. If you slow down to the level there is enough power then it will feel solid again. Obviously if the pedals start to get soft and you keep leaning you will fall of eventually on your own but at least is not a cut-off dump. The algorithm could be progressive such that as it gets closer to limit it slowly starts to soften the pedals so rider understand also alarm would be there to notify he is reaching max balance capability for conditions. Link to comment Share on other sites More sharing options...
xiiijojjo Posted May 1, 2017 Share Posted May 1, 2017 2 minutes ago, Carlos E Rodriguez said: Obviously if the pedals start to get soft and you keep leaning you will fall of eventually on your own but at least is not a cut-off dump. but wouldn't what happened to me just happen to people if they push beyond - where this " backward pedal tilt " starts which makes the unicycle disappear under you? because if you just limit how much power it'll output what happens is then at a certain speed (depending on many factors like wind and weight) if you lean forward the pedals would start tilting downwards because the unicycle is not compensating with the appropriate power needs. 7 minutes ago, Carlos E Rodriguez said: then the pedal will go soft and start tipping say forward because it is not putting higher power to keep the pedals balanced and flat to my understanding this "softness" you are talking about is the 1 to maybe 2 seconds of "backward pedal tilt" you can experience at those high speeds.But i might just not quite understand the concept you are trying to explain. Link to comment Share on other sites More sharing options...
Carlos E Rodriguez Posted May 1, 2017 Share Posted May 1, 2017 17 minutes ago, xiiijojjo said: but wouldn't what happened to me just happen to people if they push beyond - where this " backward pedal tilt " starts which makes the unicycle disappear under you? because if you just limit how much power it'll output what happens is then at a certain speed (depending on many factors like wind and weight) if you lean forward the pedals would start tilting downwards because the unicycle is not compensating with the appropriate power needs. to my understanding this "softness" you are talking about is the 1 to maybe 2 seconds of "backward pedal tilt" you can experience at those high speeds.But i might just not quite understand the concept you are trying to explain. I suppose it can be implemented as pedal tailback instead to give the same feedback to rider to back off. My thought is softness does not use additional energy to produce tilt-back. Tilt back used additional power so then you need to start the tilt back sooner to make sure there is enough margin to execute the tilt back. Letting the pedals get soggy and soggier as you approach the limit does not require more energy. Also the softness would be gradual so you don't feel like you will get dumped. The softness starts more and more, while the alarm also sounds. That should be enough to prevent cut-off. If you keep pushing then eventually you will fall off on your own but the wheel will never cutoff. Link to comment Share on other sites More sharing options...
US69 Posted May 1, 2017 Share Posted May 1, 2017 Just some small tips/advices: - first: on Gotways: the 80% beep...is NOT batterie related...it is just a beep to let you know when the MOTOR has reached 80percwnt of its performance! has nothing to do with batterie status! - second: what Carlos wants...is just not possible on selv balancing vehicles! to make it short: max speed depends on voltage...torque depends on amperage...their is no way to "slow down" a EUC when it reaches it "near max speed"....when you reach it...the motor shuts down! point! some people "dream" of a software related "just get slower, when max is reached" ....that did NOT WORK here(you would faceplant also)...the CPU just tries to balance the wheel...and keep the pedals horizontal...if the end is reached...its finish! there are just different ways to get the driver known that he is reaching the end: tiltback, vibrating, beeping...but if he choose to go further...bad luck! Then another thing: The "max speed" depends a lot of the brand! KS and Inmotion will NEVER let you experience yourself the max speed! they will set a last speed where ALLWAYS tiltback sets in...and have a big safety margain to the real "cutout" speed... Otherwise Gotway: what they announce as max speed should in NO WAY be overrriden...because on that speed is the REAL end! Please excuse me that this is my last point on discussing the "how a wheel should behave at his max speed"....because this discussion was done a hundred times before....and to bring it to a point: Every wheel will always have its "end-cutout speed"....and there is little to no way to get this changed on EUC's.......Sorry if i sound harsh...but i invite you to search the forum for this....EUCs have 2 rules: push them: they accelerate...lean back...they brake...this rule cant be overwriten... Link to comment Share on other sites More sharing options...
Carlos E Rodriguez Posted May 1, 2017 Share Posted May 1, 2017 2 minutes ago, KingSong69 said: Just some small tips/advices: - first: on Gotways: the 80% beep...is NOT batterie related...it is just a beep to let you know when the MOTOR has reached 80percwnt of its performance! has nothing to do with batterie status! - second: what Carlos wants...is just not possible on selv balancing vehicles! to make it short: max speed depends on voltage...torque depends on amperage...their is no way to "slow down" a EUC when it reaches it "near max speed"....when you reach it...the motor shuts down! point! some people "dream" of a software related "just get slower, when max is reached" ....that did NOT WORK here(you would faceplant also)...the CPU just tries to balance the wheel...and keep the pedals horizontal...if the end is reached...its finish! there are just different ways to get the driver known that he is reaching the end: tiltback, vibrating, beeping...but if he choose to go further...bad luck! Then another thing: The "max speed" depends a lot of the brand! KS and Inmotion will NEVER let you experience yourself the max speed! they will set a last speed where ALLWAYS tiltback sets in...and have a big safety margain to the real "cutout" speed... Otherwise Gotway: what they announce as max speed should in NO WAY be overrriden...because on that speed is the REAL end! Please excuse me that this is my last point on discussing the "how a wheel should behave at his max speed"....because this discussion was done a hundred times before....and to bring it to a point: Every wheel will always have its "end-cutout speed"....and there is little to no way to get this changed on EUC's.......Sorry if i sound harsh...but i invite you to search the forum for this....EUCs have 2 rules: push them: they accelerate...lean back...they brake...this rule cant be overwriten... Kingsong69. Are you an electrical engineer? the computer puts out a PWM duty cycle such that the error in tilt angle is corrected by increasing duty cycle until the error is reduced to the programmed level based on a Fuzzy logic algorithm or a PID algorithm. The computer can stop that process at any time. Say it calculates that it is reaching amps to high and stop increasing the duty cycle and the pedal get softer or like it does now engage pedal tilt back but to do pedal tilt back there has to be enough margin left so it can actually accelerate the wheel to produce the tilt back. And yes it is the software. The duty cycle can only be increased up to 100% which is full on and that does not commutate the ABC phases to produce EMF torque. So the software actually knows this and that is why it shuts down. How the hell you think it shuts down? The software does. It reaches the point that is about to exceed the PWM sequence to induce the required direction of motion and the current speed. So the lazy programmer just put in the code when you reach that point shut down the power. That is just not a complete implementation. They can make it smarter it is never allowed. I understand you have seen many discussions on this subject and guess what. They are wrong. The reason it cut off is because the software is implemented to shut down when it can not compensate any more. The software can be improved to it does not shut down but start to intelligently reduce balance response by softening the pedals and sound alarms. And yes if you keep leaning you will fall off but that is not a shutdown. Link to comment Share on other sites More sharing options...
US69 Posted May 1, 2017 Share Posted May 1, 2017 4 minutes ago, Carlos E Rodriguez said: Kingsong69. Are you an electrical engineer? the computer puts out a PWM duty cycle such that the error in tilt angle is corrected by increasing duty cycle until the error is reduced to the programmed level based on a Fuzzy logic algorithm or a PID algorithm. The computer can stop that process at any time. Say it calculates that it is reaching amps to high and stop increasing the duty cycle and the pedal get softer or like it does now engage pedal tilt back but to do pedal tilt back there has to be enough margin left so it can actually accelerate the wheel to produce the tilt back. And yes it is the software. The duty cycle can only be increased up to 100% which is full on and that does not commutate the ABC phases to produce EMF torque. So the software actually knows this and that is why it shuts down. How the hell you think it shuts down? The software does. It reaches the point that is about to exceed the PWM sequence to induce the required direction of motion and the current speed. So the lazy programmer just put in the code when you reach that point shut down the power. That is just not a complete implementation. They can make it smarter it is never allowed. I understand you have seen many discussions on this subject and guess what. They are wrong. The reason it cut off is because the software is implemented to shut down when it can not compensate any more. The software can be improved to it does not shut down but start to intelligently reduce balance response by softening the pedals and sound alarms. And yes if you keep leaning you will fall off but that is not a shutdown. Thats why i directly said that i will not discuss this anymore...... Multi million dollar companies Segway, ninebot, inmotion just had not the right software engineers to make their wheels/vehicles behave a bit better...they just missed this forum ;-) Just one question: if the rule: lean=accelerate, lean back =brake is not guilty anymore.....how the heck will your wheel at max speed, then will know what you want from it now? ooooh...you reach max speed...you will not "overgo"....but what now? stay on same speed? decelerate? stay? accelerate? brake? @Carlos E Rodriguez This is not -in no way- against you!!! Its just...think it over...if you "overwrite" the principles of Self balncing vehicles.....which is just to keep the pedal, footstand horizontal when pressuring or not.....the whole system will not work anymore! Link to comment Share on other sites More sharing options...
Raptor Posted May 1, 2017 Share Posted May 1, 2017 ( My first wheel Airwheel, was a weak and taught to ,feel before the loss of power ! ) I very much agree Carlos E Rodriguez and look forward to the wheels just his described wheel logic algorithm . The main problem is the weakness of the battery ! More powerful engines and also a control unit would not have any benefit. If you look at all the wheels for accelerations, battery huge voltage dropping occurring. It would be helpful just now Carlos E Rodriguez mentioned software . If someone would be able to produced in of such software. Then it would be a big development. But my thought explanation here : I added here one of his old post KS18 ! Because the power loss will be felt when driving and can get also compensate, so I will describe below, And here's my old post : Just in case, I write. Perhaps is for someone help ! My KS18A+ v122 has a max lift off cut off about 48,7- 49,0 km h, if battery 100% and now v1.23 for full battery 49,4kmh . I've already been several times bizarre but effective salvation. Now as soon as you feel the wheel cut off,let your feet quickly squat ( Legs well loosely ). Then decreases sharply the force vector angle. Then decreases sharply and many, over lean ! And the my KS18 wheel turns itself back on again !!! In some times, due to high speed ,it to it even several times in a row . If happened to drive while sitting, then after cut-off turned back himself right back where I stayed motionless. Too hard acceleration matter of course this have also occurred less than 40 km h. So far, this wheel saved me, if I a sudden squatting immediately, when it beeping and turns out. Typically, as well as Alex_U says,for hard acceleration reaches beeping while already the cut-off ! I have two new KS18 but second wheel lift cut-off speed only max 46.7 for full battery and therefore have not tried it with another wheel .Therefore, I do not know whether the technique would help others wheelers. Do not want to encourage anyone to test high-speed but, in a dangerous situation, maybe someone else also rescued to in such a way . I think that, abruptly squatting becomes only much weight direction for inertia in but to turn on wheel the already favorable position and speed !? All the wheels are obviously quite different because of my two equal-wheel voltage readings vary ( Compared with the actual measurement ) etc. So I can not generalize anything ! Link to comment Share on other sites More sharing options...
meepmeepmayer Posted May 1, 2017 Share Posted May 1, 2017 4 hours ago, xiiijojjo said: It's a strange design to protect the batteries rather than the rider... But from a design point of view what could you even do to add more safety at high speeds?? Nothing you can do "in software" (how the wheel behaves). Apart from the fact that the 80% is not battery related, if you generalize that to "protect the wheel from self damage rather than the rider", there's literally no better option. Either you crash with an undamaged wheel, or the wheel will even speed you up a bit to keep the balance, then it breaks anyways and you have a damaged wheel, and you still crash (at a slightly higher speed). So the unintuitive but hard truth is, this is the best option you have. If you overpower the wheel, you must crash (unless you can compensate quickly, but nothing the wheel can do) and there's no point in taking the wheel down with you. All safety measures must concern never allowing overpowering the wheel. If it happens, it's too late. -- Good points about the speeds. But the manufacturers lie like there's no tomorrow (see: crazy promised ranges). Also, turns out it is better to think in terms of power output/wheel utilization/percentage of what is maximally possible than in terms of speed. 20 km/h on 10% incline will need more power than 40 on flat pavement (a guess). So speeds really mean nothing. Instead of a speed meter, every wheel should show a "percentage" of how far you are away from where the weakest link can no longer keep up. I found the default speed beeps are a good indication of what should be safe on flat road. Link to comment Share on other sites More sharing options...
meepmeepmayer Posted May 1, 2017 Share Posted May 1, 2017 @Carlos E Rodriguez You could argue, anything but a quick shut off does just add extra energy into the system that can hurt you extra. I think @KingSong69's argument is sound, no reason to think Segway invested 100M USD but were too lazy to implement a better algorithm. Link to comment Share on other sites More sharing options...
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