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Found 39 results

  1. Hi, Here goes a topic that I think is definitely worth posting about. My partner is a physical therapist, and after I had a minor knee-tendon injury during the first few days of riding, she mentioned that warming up and stretching wouldn’t be a bad idea for EUC riding, since to a great extent, it involves maintaining the same posture for extended periods of time, which can lead to muscle, tendon and ligament fatigue and stiffness, which in turn, makes one much more prone to non-impact injuries in the event of falling/jumping off the wheel, or can potentially make them worse. For example, falling off the wheel and landing on just one leg can involve a considerable impact, and muscle and tendon stiffness (due to the riding stance and lack of stretching) will make an injury (sprain, tendinitis, etc.) much more likely, or worse than it would have been if you’d warmed up and stretched to maintain flexibility. @meepmeepmayer and @Mono mentioned that they hadn't seen this topic brought up in the forum, so I had my partner walk me through the biodynamics of EUC-riding and give me a few warm-up and stretching exercises to help minimise the over-stress that certain parts of the body are subjected to when riding. Bear in mind that a great deal more muscles, tendons and ligaments are in play while riding than I’ll list here and to cover them all would involve a lengthy, multiple installment publication (longer than this one ) that I doubt anyone would be interested in reading, so for the sake of brevity and pragmatism, I asked her to narrow down the list to the soft tissues subjected to the most stress and most prone to injury. BEFORE RIDING, you should ideally warm up a little. The best and most simple exercises you can do, that pretty much cover most of the muscles you’ll be using (legs, hips, core), are: Squats: (If you’re in a hurry, 10 squats are better than nothing, but 15 is better) Marching in place / high jog: (10 with each leg should do; for a more thorough warm-up, aim for 20) As part of the warm-up, some joint movement is also beneficial. Some of the most useful exercises are: Standing hip circles: (5-10 repetitions in each direction for each leg; the broader the circles the better) Circular knee warm-up: (5-10 repetitions in each direction) Circular ankle stretching: Aside from the warm-up, some LIGHT stretching can go a long way in terms of preventing potential injuries. I’ll detail the different soft tissue “components” of the musculoskeletal system that are stressed the most/more likely to be injured, how they come into play in terms of EUC-riding, and how to stretch them. IMPORTANT: Plantar fasciae (foot arch): (aka the part that hurts like hell when you’re beginning) Involved in base stance (the more forward your foot is positioned, the more they’re stressed) and acceleration. Stretching exercises: Tibialis anterior (muscle and tendon): Used for braking and when leaning back (e.g., going downhill). Stretching: Achilles tendon: Used while in base stance and when accelerating. Stretching: Calf muscle and soleus: Used in base stance and when accelerating. Stretching: Calf: Soleus (deep calf muscle): Hamstring (posterior thigh muscles & tendons): Used while in base stance and while accelerating. Stretching: Quadriceps: Under the greatest stress when braking and leaning back, but also tense (albeit less so) when in the base stance and accelerating (to balance out the force being applied by the hamstring). Stretching: If having trouble balancing (which you shouldn’t, you’re damn EUC-riders!), you can use one arm to support yourself on a wall, rail, fence, etc.. If you don’t feel any tension on your quads in the position shown in the video, pull your leg further back, so the leg being stretched isn’t parallel to your other leg and your knee is further back (keep your back straight while you do this). I recommend holding your foot from your ankle. Doing the same exercise but pulling from the base of your toes is another way to stretch your anterior tibialis). Hip adductors (inner thigh): Used to press legs inward against the wheel and for turning. Stretching: (Sexy Legs Workout...potentially sexist/objectifying, I know...but what can I say? I looked at several different videos for the same exercise and she’s the one that explained it the best. Seriously.) Hip abductors (outer thigh): Used mainly for turning. Stretching: In short, there are tons more muscles, tendons and ligaments involved (as in everything), but these are the main and most important ones. If you’re in a hurry, the most important ones to stretch are hamstrings, calves, quads and anterior tibialis. To stretch hamstrings + calves, follow the first exercise in this video. Just lean forward to stretch your hamstrings (with your foot relaxed), and do the same thing but pulling the end of your foot towards you to stretch your calves. For quads and anterior tibialis, refer to the comment below the quadriceps stretching video. Additional tips: When falling, your reflex reaction is to use your arms to break the fall. Protective gear helps prevent injuries from the impact part of a fall, but as others have pointed out (in regen-related threads), energy can neither be created nor destroyed, only transferred into another form. Meaning, in this case, that the abrasion resistance that wrist and elbow guards provide allows you to slide, thus reducing the intensity of the impact, but also transferring that force upward, towards your shoulder. This creates a high risk of shoulder injuries and dislocations (which are painful as hell), so it’s definitely worth strengthening the muscles involved in keeping the shoulder in place: mainly deltoids (rear and front), pectorals, and the latissimus dorsi. Strengthening biceps and triceps isn't a bad idea either. (All of the links above are for strengthening exercises). It's also important to point out that you should always stretch after strengthening exercises, as flexibility is just as important as strength, and not doing so will lead to muscle stiffness. And lastly, the better shape you're in, the less prone you are to injuries. And so this doesn’t turn into a multi-page soliloquy, I’d say those are pretty much the basics (glutes and abs also play an important role in balancing and forward/backward motion, for example, but are unlikely to be injured when EUC-riding or lead to unrelated injuries). All the same, if anyone thinks I missed something important (perhaps your partner, @Elzilcho), don’t hesitate to add it, nor to correct me anywhere I'm wrong or suggest alternative, easier/better exercises I know it’s a drag to think you have to do all of these every time you want to hop on your wheel, but these should actually only take 5-6' before riding and 10-15' max. post-riding. Otherwise, an abbreviated version, or stretching them at another time several times a week (after exercising; avoid intense stretching of muscles that haven’t been previously warmed up) is definitely better than nothing, and can go a long way in terms of preventing a broad range of injuries (particularly ankles and knees). In any case, I hope this is useful (it feels nice to be able to give back to the community after pestering all of you with questions since I joined the forum). Happy (and safe) riding! Sidenote: I’ve tried to be as neutral as possible and find an appropriate "male/female/elderly physical therapist" ratio for the Youtube stretching exercises, because I feel it's the right thing to do, and because I know the subject of posting content of bikini-clad women and scarcely-dressed female EUC-riders has been discussed in this forum. My apologies to those hoping for more cleavage & yoga pants
  2. MetricUSA

    Tricks to Learn

    List here different maneuvers here to make yourself a better rider or to have safe fun....
  3. We live in an area where there are lots of steep climbs. They are not really steep, but they have given me problems with unexpected push-back from day 1 with the MiniPRO. There is little data available on exactly how much power the MiniPRO motors can deliver, and how this translates into speed on either flat or sloping surfaces. The best source of information was shown to me by JoJo, it is a blog about the MiniPRO development cycle at Ninebot: http://bbs.ninebot.cn/forum.php?mod=viewthread&tid=4100 Google translate produces this for a key section of the blog: "We have done a lot of power test experiments. The results show that when the weight of 100kg people climbs 15 degrees at 5-6kmh, the power demand of the whole vehicle will reach 400 watts or more. If the slope is slightly accelerated, the power will rise to 800 watts. The tester weighing 120kg may reach 500 watts when driving at 20kmh, and the output power of the car may reach 1000 watts to 1200 watts when it accelerates to 30kmh." So, I read that as saying a 120kg person riding on flat ground will need 500W of motor power to reach 20Km/h, and 1000W-1200W to reach 30Km/h. The continuous limit of the motors is "350w / short time 1050W, and the maximum torque of a single motor is .. more than 35Nm." So the firmware has to decide when to start pushback whenever the continuous output power being used is greater than 700W, or else the motors will overheat,and likely the battery pack too. Here is the 19 degrees street that the MiniPRO design team used as their reference for the "World's Steepest Street" But they eventually decided on planning for a 15 degree slope, less steep than this one. They planned "100kg people climbs 15 degrees at 5-6kmh, the power demand of the whole vehicle will reach 400 watts or more. If the slope is slightly accelerated, the power will rise to 800 watts." This represents the totality of the engineering specifications I have been able to find about the MiniPRO When I measure myself, a new N3M320 MiniPRO which has not yet done 50Km starts to push-back at around 9Km/h on the steepest steady hill I have around here, which is 6.5 degrees. I weigh 94Kg (in riding boots). I see no difference between firmwares 1.1.7 and 1.1.9 except that 1.1.9 has the gentlest pushback cycle (it beeps a warning before making you jump off ). With 1.4.1 it is tough to even reach 9Km/h because it is continually adjusting the push-back point. An N3M260 which has long-ago reached its 50Km transition can reach 11-12 Km/h (with v1.1.9 FW) before beeping and starting kickback. The max speed is the same whether I am using the smaller 243Wh or the full 310Wh battery. So there clearly is a safety margin which the firmware holds in reserve to try and preserve vehicle integrity. Yet how the firmware implements this push-back reserve is (IMO) flawed, as it also seems to limit the ability of the MiniPRO to handle potholes and pebbles until the 50Km mark is reached. I will be watching very carefully as my new N3M320 reaches that target, and then do a complete reassessment of the vehicle's hill-climbing ability... Finally, I note that the older N3M260 had the 90/65-6.5 knobbly off-road tyres fitted, running at 15psi, while the new N3M320 has slightly smaller 'off-road' tyres, which should have given it an edge in torque, but didn't. Only when I get to 50Km will I be able to decide how the firmware handles safety reserves when larger tyres are fitted - there is a possibility that the slope climbing speed limit is set by a firmware algorithm, and not by the motor power exceeding 700W. Please share any data and experiences you have had negotiating slopes with the MiniPRO.
  4. I see many videos of unprotected riders, as well as riders who wear differing amounts of protective armor depending on the ride they're planning. What's the minimum safe amount for a low speed ride? I recommend this as a test. Take your wheel outside on the pavement. Stand next to a wall. Lean the back of the wheel against the wall. Don't power up your wheel. Mount your wheel then gently push off. Try to hold your balance, but feel free to fall forward and try to catch yourself when you no longer can. This is what falling off a wheel would feel like at no speed. Any forward momentum at all would make it much much worse. If you are able to get up without injury, then your protection works. If you break your wrists, ribs, shoulders or smash your face, perhaps it would be time to order some better protection once you're back from the hospital. Not brave enough to try? Can't say I blame you. Maybe think about it next time you take a low speed ride....
  5. I was looking for recommendations for a headlamp that would fit well on my helmet (https://www.amazon.com/gp/product/B00O5E72KI/ref=oh_aui_detailpage_o07_s02?ie=UTF8&psc=1). Ideally the headlamp would be rechargeable, have different light modes (like strobe effect) and also a rear light for added visibility. Here's one I've found on Amazon, but before purchasing I wanted to try and get some feedback from the forum to see what others may be using or have for input. Thanks! https://www.amazon.com/Mifine-Waterproof-hands-free-headlight-Rechargeable/dp/B016Q8G9OU/ref=sr_1_4?ie=UTF8&qid=1495632717&sr=8-4&keywords=headlamp+biking
  6. Liam MSuperV3

    Gotway MSuper Queries?

    Hi guys, I've been wheeling around now for about 10 months and have a couple of queries about my MSuper V3. I've become a very confident rider now and I have my first two alarms disabled. Does anyone know what speed the third alarm will come on at? I've not heard it yet. Also, how is your top speed affected by battery power? I'm quite cautious whilst riding at around 20% (Normally to get home). Any advice is greatly received. Thank you Liam
  7. Mimir

    Crowbar redundancy

    Problem: if a MOSFET fails on your EUC when in use, you faceplant. And MOSFET failures are most commonly under load, which often means high speed, which means a significant safety hazard. Solution: Stick two control boards in there, so that if one board stops working the other can take over. New problem: MOSFETs tend to fail short- so the second control board won't be able to drive the motor, it'll just be driving (at least one phase) current into a dead MOSFET. And this is, as far as I know, basically where things are- more reliable wheels just have higher-specced FETs, more in parallel, better cooling, more conservative limits, etc. (Where you do see dual-board redundancy, it seems mostly meant to protect against things like gyro failures, software bugs, etc, or in some cases (like on the Ninebot One S[12]) two redundant battery packs too, providing some protection against BMS issues and bad cells.)). So, is this the best that can be done? I think there's a better way. Shown is a simplified driver bridge for one phase of a motor. In normal operation, board B does almost nothing (it's possible board B could be a separate, smaller board with only the motor driver components, to save cost). However, it communicates with board A over I2C or something, and detects when M1 or M2 fail. Periodically, it tests itself and monitors board A. If M1 or M2 fails open-circuit, board A deactivates itself and board B uses M3 and M4 to replace M1 and M2, maintaining a stable ride. If M1 or M2 fail short-circuit, though, board A *hopefully* deactivates itself (it doesn't actually need to do this, which adds a bit more reliability), and board B *also* deactivates itself (turning all FETs off). Then board B turns M3 on if M2 failed, or M4 on if M1 failed, until it detects its current draw fall to zero. By doing so, it shorts the battery pack through (without loss of generality) M1, F1, and M4. Since M1 is acting like a short, this means F1 and M4 together see almost the entire battery pack short circuit current (approx. 1 gazillion amps) which very rapidly blows F1. We have now reduced this case to the open-circuit case- M1 and M2 are totally disconnected from the motor, and the ride can continue. (In practice, this condition occurring would trigger a controlled shutdown of the wheel (beeps, tiltback after a small delay, followed by refusal to power back on until repaired.) This solution provides redundancy against an open or short failure of any one MOSFET. If F1 is placed at the end of the motor cables near the motor, and two redundant motor cables are used, separated physically, it also protects against melting motor cables. If two fuses are used in a Y configuration, and if board A performs the same checks on board B as board B does to A, a short-circuit failure from M3 or M4 (while board A operates normally) can also be handled. However, since M3 and M4 pass no current during normal operation (and are likely on a separate, very cool, heatsink), the chance of them failing under normal operation should be minimal. It's important that board B check M3 and M4 during the wheel's POST, to ensure that they're still working (since otherwise a failure of them would be silent, not noticeable, until you need redundancy and don't have it.) If two redundant battery packs are used, board A and B can coordinate in normal operation to share the load between them (and blow the fuse to isolate a malfunctioning board and its battery in the case of a failure), or, possibly, a separate board could handle balancing load between the two packs and isolating a misbehaving pack. Some problems remain. Notably, the fuse needs to blow, and blow fast; at a huge overcurrent (10x rated capacity) a fuse blows in something like 25ms, which might be a bit of a jolt to the rider but shouldn't cause a faceplant. Also, M3 might fail when the battery's shorted through it- just when it's needed the most- to prevent this, some sort of relay might work, but finding relays with sufficiently high current ratings and low on resistance in reasonably small packages is difficult. Thoughts?
  8. I hope this is a useful poll to learn more about which protection gear forum members typically use and how serious injuries from EUCing are.
  9. volavoile

    Safety speed with your EUC

    Hello, French Wheeler, but not as good as some other, I had a bad accident (broken shoulder, now with some metal!!) with my small ninebot one E+... and I spent some time in order to understant why we face cut out or accidents. So, on the forums, I could recognize 4 kind of accidents : 1- Pilot did ignore alarm.... nothing to say.... too optimistic, 2- driving accident (bumps....), 3- Sudden cut off.... (looks like my accident, but I'm not sure it wasn't a technical failure), 4- Technical failure. Rare since construcors did improve the safety...or correct bugs (BMS for instance). For the point 3, I did some calculation, that shows that specification of constructors seems to be far too optimistic, and the speed alarm does not consider the wheight of the pilot... which has a huge impact. What I did consider is a common case of accident : you run on flat road, no alarm, straight... and you have a small slope (not big, couple of meters long!). So immedialtely, since you do not consider you have to slow dow, your Wheel has to give all power in order to maintain the speed during the slope. In this condition, considering a 10% slope (not big at all, it is a 6° angle road), what is the maximum speed you can run? I did consider air drag, which has a big influence over 30 km/h), the solpe that I consider as a safety margin, and the wheight of the pilot. The power was considered as constant whaterver the speed is (optimistic), and, since nobody know the duration of the peak's power, 0,5 second for this peak (which is only use for bumps in fact!). Yield of the Wheel in order to transform electrical energy to mechanical energy is estimated at 75% (tests on some gotways). What do we calculate show that with a 500 W, at 25 km/h, you're not save at all... except if you are a kid. On a gotway ACM our MS3, 45 km/h is not a realistic speed since air drag consume most of the power... What do you think? Conclusions : - Power, and slow speed is the key for safety... - Adapt speed limit cosidering your wheight, - If you want to keep the hight speed limit, go quiet, and in all case, use protections!!! Of course, this is only my caclulation, an you can disagree! EUC safety speed.xlsx
  10. I would ask you to share your experience and opinion about EUC accidents, their causes and solutions. We need this exchange of information for our safety and for avoiding that EUCs will be forbidden by laws in the future because they are too dangerous. Please keep every accident very very short and to the point. Here is my experience after >9500km: 1st EUC: unbranded unicycle 14" wheel 300W nominal: - motor cut-off at 15km/h, not even fallen, I continued running => don't buy unicycles with very low speed limits, with very low power! - smaller wheels makes you slow down at every discontinuity on the road (pavement, pits) and they can make you loose your balance (=our main fear) and fall more frequently at non-flat roads => buy bigger wheels for riding stability. I think even 16" is not big enough. my next EUC will be again 18" and not the Gotway Tesla because power is nothing without control. The rest is with Gotway Msuper v2 18" 1000W nominal, speed limit 45km/h: - balance lost but not fallen, tilt forward at 45km/h without helmet, motor did not cut off (if it did: I was nearly dead) (what is tilt forward? => when reaching max. power the motherboard keeps on delivering max. power instead of cutting the current: so you lean forward but without acceleration of the wheel but without cutting off of the motor too, this makes you loose your balance in forward direction, if you react quickly by leaning backwards you save your live which was the case here) I was not fallen but I lost during a second my balance to forward direction but this was the most dangerous incident I ever had => buy a EUC with backward tilt before EUC limits (was not the case for GotWay!) , buy EUC which continues delivering max. power at his limits (Gotway is very good at this point, he knows that motor cutoff is the worse thing that a EUC can do, it avoids at all prices) - fallen at 5km/h: at day I ran in a large tunnel where it was a little dark (since I ran at day I did not had my light on), I saw a pit of 15cm, I leant heavily backwards to brake, the motherboard gave his full power to brake again without cutoff, I leant so heavy backwards that I fell backwards at +-5km/h, no injury =>buy a EUC that keeps on max. braking power without cutting off (Gotway is good at this point) , buy a EUC with very powerful lights (even new EUCs have tiny lights which are insufficient to see dips on the road), buy bigger wheels since I would fall forward instead of backwards in this case if I had a 14" wheel because a 14" wheel can fit more in large dips. - insufficient braking power: due to my heavy backpack and at low height (maybe it is my weight which is relatively low in comparison with total weight) I braked too heavy so that Gotway could not increase braking power after reaching it max. braking power => I lost my balance during a second to rearwards direction, I reacted quickly by leaning forward to decrease my deceleration. => by a EUC with high power so that your motor can brake with high deceleration in case of need. again no motor cutoff after reaching max. power (very important) - fallen at 5km/h, at standstill I accelerated so much that motor reached max. power and kept this max. power to save me but this time my backpack was too heavy so that I could not react at time to decrease my forward leaning ( I am not used to ride with backpacks, so I had to be more attentive, my fault), I fell forward at +- 5km/h with a full cover motorhelmet on, small injuries but the full helmet did his job. => 3kW motor did not give enough acceleration power => buy EUC with highest power. I would like to know what solutions there exists for overheating of mosfets. Fans? passive cooling with the wind? susceptible for dust? battery and motherboard behaviour at end of their life.
  11. Well def, gunna go ahead and get myself one of these and start cruising soon... Can anyone briefly break down a list of the euc with the best speakers? Def want to incorporate being a portable jukebox... And if anyone can point me toward 'Buying Safety Equipment 101. I figure good knee / shin pads, elbow, wrist and a good faceplate resistant helmet... That sound about right and good to go?
  12. Now it's personal. This is the master list of micro unicycle brands, categorized by safe electrical behavior. This is the thread to read if you want to buy a uni that "doesn't actively try to kill you" (@esaj). Problem One: BMS shutdown Most popular low-priced generic style brands, and many other popular brands of the last generation, are made with an electric bicycle style battery management system (BMS). This part can try to protect the battery and shut down instead of protecting the rider, even in the best conditions. This means, the unit stops working unexpectedly. This WILL happen one day if you have a uni with this design, because as the battery ages the likelihood of this phenomenon occurring increases. It is possible to modify the badly designed BMS using the "shunt mod." To be absolutely clear, a modified BMS is not the same as having a unicycle that was designed correctly from the start. Examples include Airwheel, Firewheel, TG, Rockwheel, early Gotway designs, many other brand names, and most generic imported models. Even Ninebot has a battery management system with unknown variations. Problem Two: Main board shutdown As the battery gets lower, the voltage decreases. With lower voltage, a higher current is needed to produce the same power to the motor as with higher voltage. This causes heat, and if it gets too hot, the unicycle will shut down. This problem is solved in units with safe low-battery behavior, for example Ninebot has a slow operation on low battery. Speed can also cause main board shutdown. Most brands tilt back and beep to tell you to stop going faster, and some talk to you. Some unicycles will just go faster and faster until they turn off because the motor can't take it anymore. Gotway, Firewheel, and Rockwheel are examples that will experience a speed-cliff type mainboard shutdown ie designed to kill. The goal: An electric unicycle must NEVER, EVER, EVER turn itself off unexpectedly. Ever. This phenomenon must be designed out of the equation. Manufacturer established solutions: Solution one (BMS Shutdown): Better BMS design. The battery management system has no way to conduct shutdown. Low battery tiltback / slow down. When the battery is low, instead of allowing normal riding, the unit slows down or tilts back to make it difficult to ride. Solution two (Mainboard Shutdown): Better main board behavior. Locking low battery - The unicycle should warn the rider of a low battery extra early, and slow to a stop entirely when riding is unsafe. The uni will be non-functional while still partially charged, and will not be ridable until it is charged again. This is called locking low battery behavior, and both Ninebot and King Song have behaviors close enough to this to solve the problem. High Speed tiltback - Almost every brand of unicycle avoids high speed shutdown by tilting back at high speed, so that the user can't push the uni past its limit. Every brand except Gotway, Firewheel, and Rockwheel and a few others are safe in this way. The high-speed warnings, however, must be obvious enough to truly protect the rider from pushing too hard. Solution three (batteries being sold are too small) This is on you! Buy the biggest battery you can afford. If you're going high speed, don't settle for 340wh or less. Look for something 600wh or above. And leave some wiggle room at the end of your battery no matter what; don't use the full range. Incomplete list of brands Very Dangerous: TG / OEM models of the same design - All models have both problems. F-wheel - BMS shutdown, maybe mainboard too. Suggested "buy to find out quality." SML / OEM models of the same design - All models have both problems. Airwheel - All models have both problems. Firewheel - All models have both problems. Firstwheel - All models have both problems. Rockwheel - All models have both problems. Fosjoas - All models have both problems. Suoku - All models have both problems. Huanxi - BMS is unconfirmed as safe, but has safe low battery behavior. Less Dangerous: Gotway - Older versions have both problems. Newer versions just have problem 2. Inmotion - Could be safe. Awaiting answers from manufacturer. IPS - Problem #2 has been documented in the forums. Safest: King Song - All of the problems documented here are addressed in all known models. The safest brand available right now. Please submit arguments! Ninebot (early models may have bad BMS). Despite their size, it is difficult to get answers from them about this issue. The only brand that is documented to shut down due to overcharge going downhill. This occurs on full battery because of regenerative braking. Can people submit comments about other brands that do this? Solowheel - Probably safe; need more detail. Obviously this list is nowhere near complete. Any input or criticism of the thinking presented here is more than welcome! No one here can do this alone. As the trend setters, we need to to make sure that new people getting started with this technology, and in particular innocent bystanders, will all be as safe as possible. Conclusion: There are solutions to all of these problems, but most manufacturers aren't implementing them. If we don't solve this problem, electric unicycles WILL hurt people, not only riders but bystanders as well. ALL electric unicycles will eventually become demonized in the public image, and will likely be made illegal or heavily regulated in many locales. Thus, any trade off is not only worth it, but entirely necessary. Any manufacturers who won't comply with these safety requirements need to be publicly exposed and driven out of the market. We need to protect new riders from manufacturers who don't care about their safety. So, anyone know other brands with confirmed electrical characteristics that are definitely safe / unsafe with regards to unexpected shutdowns?
  13. I have this, mostly in the winter time: https://www.mayoclinic.org/diseases-conditions/low-blood-pressure/symptoms-causes/syc-20355465 Anybody else deal with dizziness from low blood pressure, low blood sugar, or medication? I eat very healthily, and skip meals/fast once in a while. I also probably have low sodium from my healthy diet. Skip a meal while having low sodium and low blood pressure in general causes dizziness when I stand up. It's not supposed to be a health concern in general, assuming one isn't riding a damn unicycle. Anyway just wondering if anybody else deals with dizziness. I'm learning to ride my first wheel, and it can take 5-10 minutes of standing up and practicing with a hand on the wall before my balance is really confident. I suspect that this may be an ongoing issue even after I master riding the wheel. I'm considering ski poles as a safety precaution, especially after Rehab's accident. Or maybe something like this
  14. Tilt-back is a mechanism to incentivise the rider to slow down. The mechanism is simple: the neutral inclination angle of the shell and hence the pedals is changed from horizontal to negative, tilting the pedals back This gives the rider the incentive to initiate a slow down (see also below). Here I discuss my understanding of the energetic (and a few other) consequences of tilt-back. Remember the feeling to lose the ground under your feet when the tilt-back sets in? Here is why. Simple geometric consideration reveals that if the riders feet stay in contact with the pedals, tilt-back raises the riders front feet and lowers the riders heels. Lowering ones heels feels like losing support and means that the riders body lowers as well if the heels remain grounded. The effect from the centre of mass: most of the work to raise the riders body (or the toes ) is done by muscles, hence the energy comes from the food the rider has digested. (Lifting 102kg by 1cm loss-free needs about 10W=102*9.81*0.01W for one second or 100W for 0.1s thereby adding 2.78mWh=10/60^2Wh=0.0024kcal to the potential energy of the rider). However not only the rider needs to work: when the wheel pushes the rider forward (or backward), straightening up or raising the riders body adds momentarily to the riders perceived weight and hence to the power demand of the wheel. Vice versa, bending the knees or lowering the body gives the wheel a short period of decreased power demand (perceived decreased rider weight). Lowering by 5cm would remove the entire rider weight for 1/10 of a second. This is definitely something one should exploit in any critical situation: the reflex of bending the knees to keep or restore the wheel under the rider is a life saver! I had two or three quite surprising saves from intentionally going rapidly-almost-falling-like deep into the knees. Unfortunately, going deep into the knees is particularly difficult and somewhat physically limited under tilt-back. Yet, soft knees are our suspension. Soft knees get us over bumps and out of potholes. Bending knees is THE invaluable reflex when riding an EUC. But I digress... First summary: when tilt-back sets in, the riders heels lower and (without body posture change) the riders centre of mass lowers and this leads to a small and short but possibly notable power demand reduction. The effect from the change of tilt angle (here I stand corrected): because changing the tilt angle backwards increases the speed of the motor traveling relative to the shell, changing the angle requires energy. The amount however seems to be rather miniscule. If we travel 20km/h=5.6m/s with an 18" EUC and change the tilt angle from 0º to -10º in 1 second (pretty scary, IMHO), the shell position changes over the wheel circumference by 4cm = 10/360 * 18" * π. Hence, the circumferential rotation speed increases for 1 second by 0.72% = 0.04m/5.6m, i.e. by less than one percent. I am actually not sure what the power demand of this mechanism is (between 0 and 1.4% seems a good guess), but to all I can tell it must be negligible. Tilting the wheel also lowers its centre of mass. Lowering 20kg by 1cm in 1s may deliver 2W for 1s at most. Second summary: all in all, I do not dare to decide whether the effect from titling the wheel saves or demands a very small amount of energy. For the remainder, the simple but conclusive approach is to considered energy conservation: any consumed energy from the battery must be converted into kinetic energy or potential energy or heat. After the tilt angle has changed, from the energy balance perspective nothing is different to the situation before. If the wheel consumes additional energy, it produces more torque. More torque leads to acceleration (hence energy is converted to and conserved as kinetic energy), just as it happens without tilt-back or while the tilt-back sets in. Some people feel that under tilt-back they apply more pressure to the front foot, or equivalently, that the wheel applies more up-pressure. This means that the wheel produces more torque to provide this counter pressure. Torque however invariably leads to acceleration of the wheel (or the wheel and the rider). The other way around, if the wheel does not accelerate, this feeling is a perception due to the uncomfortable foot position but not actually an increased up-pressure. Finally, slowing down the wheel, with or without tilt-back, can be accomplished by initially accelerating the wheel to the front of the rider. Tilt-back is the invitation to do exactly this. In particular, if the rider does not adapt to the changing neutral tilt angle, the wheel accelerates (without the rider and quickly). This acceleration requires some additional power (less than the acceleration of wheel and rider). With the knee-bending trick applied immediately, the additional power to initiate braking can at higher speeds probably be reduced to zero.
  15. I started to compile a list of riding skills that I myself found somewhat relevant for safety. I have been practicing all of these (and many more which didn't make it to this list because I do not deem them relevant enough for riding safety). The bad news: lack of riding skills is IMHO not the most important safety concern. The greatest safety hazards as far as I see it are speed (in combination with potholes, hidden corners, the natural power limits of EUCs, etc.), overconfidence, lack of knowledge of EUCs capabilities, fast moving heavy objects like cars, and complacency. Now let's go to the meat, a listing of relevant skills with a few tips: Beginners: a learning belt is of good use to prevent the wheel from running away hitting and getting between the legs after hopping off getting lots of scratches (not a safety concern though) relax, remain upright, look ahead (not down), avoid to fully straighten the knees avoid using the arms for balancing, instead twist the wheel left-right to balance and use the feet to control the wheel important: be always mentally prepared to hop off when hopping off, focus to stay away from the wheel. The wheel may hit your legs and this hurts and can lead to (usually minor) injuries or it can be a stumbling block to fall over learn to brake Intermediate, learn and/or practice to: brake hard, I haven't yet stopped to practice emergency braking almost every day minimise arm movements and let the feet do all the control of the wheel and balancing instead; this means to give leverage to use arms in a critical situation when they may be really needed be mentally prepared to run off and away from the wheel (without a learning belt) avoiding to let the wheel hit you or get into the way between the feet after separation; I am not exactly sure how to practice this intentionally, but I usually lose the wheel a few times during a single play-around session (on loose ground), which gives practice in a relaxed setup put, at the same time, almost all weight to the tip (the ball) of one foot and to the heel of the other foot; it is not too difficult to even lift one heel and the opposite front foot at the same time; this is a first step to freely position the feet on the pedals while standing with one leg on the ground, "lock" the wheel with the other leg; in this position, move the wheel anywhere around with the loose leg, also further away from the supporting leg thereby spreading the legs and distributing weight to both legs keep the upper body vertical; lean forward (and backward) by bending the knees (and moving the hips slightly forward and less slightly backward), not by leaning the upper body most important: keep the knees soft; soft knees are our suspension and allow to negotiate anything unexpected on the ground (bumps, holes, slippery spots) and go over curbs of 3-4" relatively easily (depending on wheel size); I manage 5" curbs on a 16" wheel with this technique. Keeping the knees soft enough needs quite some practicing, unfortunately. go over speed bumps with soft knees such that the upper body doesn't move vertically at all; fixate a point with your eyes to know whether your head has moved most important: acquire the reflex to bent the knees in any critical situation; many if not most critical situations can be saved this way; when separating from the wheel, the body should always be low enough that the heels of the feet can touch the ground instantaneously; flying in the air means giving up almost all control over the further course of events, being closer to the ground means to have a larger area available where to firmly place the next foot turn the head into any possible direction, include up, and keep it there for a couple of seconds; look anywhere, including and in particular behind or nowhere (closed eyes) Advanced, learn and/or practice to: dismount effortlessly and smoothly (with bent knees); ideally, the mental effort to dismount is small enough to never be tempted to hold onto something for dismount avoidance; consider one foot on the ground as part of the natural riding process fully relax the arms; like when walking, the aim is, for example, to be able to effortlessly take sunglasses out of their case and put them on while riding ride on any surface you can get hold off, the more slippery or the softer the better (start slowly!), search for longitudinal grooves to ride over, and keep the arms relaxed brake hard on a downhill slope move/position the feet freely on the pedal while riding while driving moderately slowly, touch the ground with one foot also putting weight on the ground foot; the ground leg must always stay away from the wheel to not clip the leg with the pedal; keep the body low enough such that the heel can reach the ground; easier to begin while riding a curve ride down stairways; when on stairs keep ground contact as long as possible, think of each stair as a bump, think of skiing mogul, apply a (slightly) tighter grip on the shell as usual; start with 2 stairs, then 3... turn the hip, like for sitting down to the side; mastering this move gives more leverage to look anywhere around and behind and to take tight turns riding backwards, at least a little. Start by moving one inch backwards after braking to a full stop and increase the distance gradually. I always practice both sides, left and right, when applicable. Of course many of these could in principle be combined, showing that the movements have become automised. Many combinations I am not capable of doing (I can't climb a larger curb with closed eyes or run off the wheel while putting on the sunglasses Based on my experience and on reports of many others, clipping a curb or a wall or anything on the ground with the pedal or the foot is one of the main reasons for unexpected falls of more experienced riders. I started to experiment practicing this situation, but can't say for the moment whether this is likely to be of any help.
  16. hey riders, a few hours ago I flew right across a hood going approx 10-15kph on my wheel. A car driver crossed the bicycle lane turning right into a shopping center without giving a second thought to me. Luckily I wore almost full protection (no helmet!) and only my wrist guards got scratched. The wheel came to a halt running into a hedge. did you get in familiar situations? I can only guess some inattentive drivers mistake EUC riders for pedestrians. The accident happened in daylight, though for me this is the final wake up call to always wear my full face downhill helmet from now on. I might even order some extra lights for the helmet as well as one of those ugly high visibility vests. btw I was so stunned by the behaviour that I forgot to swear and claim a new pair of unscratched wrist guards. Guess I got off cheaply today. (the car driver too)
  17. I am using Slime in all my wheels and had recently my first two punctures after almost 8000km. The good news: I could recognise a tiny leak by fluid leaking from the valve stem before I even noticed a loss of air pressure. Slime also helps a lot to find the location where the tube is leaking, as the leak spits out the fluid. The bad news: even a comparatively small puncture wasn't fully sealed. Repair becomes slightly more difficult, as, I believe, vulcanisation only works on a Slime-free tyre and the leak doesn't quite stop to spit out Slime. Overall a tyre sealant is a safety improvement, so I will keep using it. I just wonder whether there are better products out there than Slime.
  18. Hello all, I'm used to go down a hill daily with my ACM 16 820wh, around 650meters length and 65-7meters height. That gets me an average of 10% slope with variation between 0 to 20%. Last 2 days, i got a worrisome phenomenon that happens when i go down : even with weak speed (10km/h), a little braking can be troubling. Pedals start getting tilted, and motor alarms starts bipping to death. Lucky me, I've not yet experienced a cut off at this point, but this is really annoying. I had this kind of problems with average speed 15-20km/h, and started to chill out and going slower to avoid any problem. But now, it's coming back to haunt me at low speed... @Marty Backe i know you're the ultimate gotway user, anything to relate to this ? You probably had experienced this, no ? I know some cases of Ninebots or small motors >800W cutting off in big slope, they couldn't sustain the effort of braking. I'm still surprised to be so close to 80% motor power with my ACM 1500W and full battery capacity. It behaves still okay on flat ground, with hard braking and acceleration. Well, my motor axle feels a bit tired with time, will probably broke in a year or less. I wish to discuss about some points with you buddy-wheelers, what are the recommendations and solutions to go down a hill with 100% safety ? I guess the less you speed up, the less i risk to get huge W consummation spikes when i brake What about taking my wheel backside ? If there's a side to drive it, maybe going in reverse could be better to brake ? Might be a stupid idea right there. Bigger motor needed ? Hello Tesla, KS18L. Can wheel size have influence in braking power ? Small wheel can deal with it easier ? Can weight positioning on pedals influence the braking system ? I would say no, but so much physical parameters, speed, weight, slope, what's your view about this ? A little picture to illustrate the idea : I wish you'll come out with more advice on this, i'm a bit short on ideas right now. It's so frustrating to be going down a hill at the speed of a walker. Thanks ! PS : for those who'll come to say "just don't brake dude" => No.
  19. I bought some wrist guards finally, because I am a guitar player and I can't keep taking chances with my hands. So I purchased my wrist guards, typical standard ones and as soon as I tried the first trick they forced me on to my elbow instead. With basic stiff wrist guards you can cause a fracture further up the arm as well some finger injuries. I found these, they're $30. I wanted these but they go up so high and most of all they are about $65. Fractures further up the arm are a real hazard with the typical style. So this could be the ticket. Not sure. This is the footage of me falling onto my elbow.
  20. Got some scissor skills practice to provide extra safety to my miniPro's: All it takes is 10 min plus some 3M reflective tape. Red tape on red spokes and grey/white on grey one.
  21. I wonder if this can even be pinned down to any coherent answer, riders and wheels both being built so differently, but humor me if you will and share your opinions and/or experiences. Do you step off your machine when a curb comes along? Do you go up or down stairs on your wheel? Jump? Do you slow down or speed up to do it? How safe do you think it is to do any of that, either for your health or your machine? Would you recommend it or advise against? And do you yourself practice what you might think should be preached?
  22. Dear EUC Pioneers, Nothing spoils the joy of EUC riding more than a painful accident. For pure luck, I was spared any serious injuries so far, but when I'm honest to myself, that's way more due to luck than skill. Any fall at higher speed and I am way out of my league to cope with that. Most likely, I end up flat on my face, ruining arms and knees on the way down. Inside our Berlin riding group, we got such a wake up call lately, when one of the members shattered his forearm just days after receiving his shiny new high performance wheel. That got us thinking. As we don't know about any established EUC safety training, we attempt to invent our own. Here you will find a first concept along with the friendly request to contribute your ideas and feedback. Of course all of you are more than welcome to copy, use and improve all or part of it - it's positively Public Domain! Status: First Draft, June 4, 2017 by Tilmann Exercises Mounting / Starting: Training Goal: Mount and start from flat ground without assistance without leaving a narrow track (approx. 1 foot wide) Activity: Mark a narrow track on the ground with tape and start trying... Training Goal: Max. accellaration w/o ‘overlean’, i.e. achieve the fastest possible acceleration without overstressing the wheels power. Activity: Force an ‘overlean’ at safe speed and ‘run-off’ (should not be difficult with a weak 350W motor). Repeat the exercise to find the best leaning angle that just works. Braking: Training Goal: Break to a stop in minimum distance (from a straight path). Activity: At very low riding speed, lean back violently to force a motor cut-out. Repeat the exercise to find the angle with best braking action. Training Goal: Break to a stop in minimum distance (from a turn). Activity: No idea, we just have to try... Riding / Stabilizing: Training Goal: Master uneven ground (tree roots, potholes, street curbs, speed bumpers, etc.). Activity: depends on what the respective playground has to offer. Ideally, include some round rods that roll away when you ride over them. Training Goal: Circumvent static obstacles (like the ever so popular bicycle barriers). Include ducking under higher obstacles like branches and gates (“ewheel limbo”). Activity: Various obstacles will be simulated with tape. Supporters to hold the tape in mid air for the ducking exercises. Training Goal: Master dynamic obstacles (something/somebody surprisingly runs in your path). Activity: A wider track (approx. 3 feet) is marked on the gound. While the trainee rides on the track at safe speed, a supporter on the ground is challenged to get the rider off the wheel by throwing a soft inflatable ball from a distance at the rider or in his way. Training Goal: Master inclines and down hill. Activity: Using the weak 350W training wheel, we excercise riding up and down the steepest incline we can find. Ideally, the incline is steep enough to overstress the wheel to cut-out at safe speed. The training ground needs to provide a safe “landing zone” for the rider and the wheel as provoked dismounts on the incline are part of the training. Training Goal: Change foot position while riding. Activity: Train to ride with just one foot on the pedal. Begin with placing the strong leg on the wheel and use the weaker leg for “skateboarding” the wheel in a straight line. Exercise, until you master several feet riding on one leg without touching the ground with the other. Gradually increase difficulty with switching legs, increasing distance and speed and including turns. Once you can lift a foot while riding, changing foot position on the pedal is a piece of cake. Variation: Include exercises to sit down on the wheel and stand up again while riding. This will also build up balancing and stability. Check training effect by mounting and starting with choosing a wrong foot position on purpose, then correct it when in motion. Training Goal: Minimum speed riding. Activity: Mark a narrow track on the ground with tape. Mark a start and a finish line. Train to ride the track as slow as possible without leaving the track, putting a foot down or reversing. Have a supporter take the actual riding time. Training Goal: Look behind while riding. Activity: Mark like 3 cardboards with letter easily readable from a distance. Mark a narrow track on the ground with tape. After the rider passed a supporter on the side, the helper holds up a card board and calls the rider. The trainee then tries to look backwards and call out the respective letter without driving off track in the process. Gradually increase the difficulty by moving the supporter closer to the track until he is placed straight behind the driver. Also gradually increase riding speed. Training Goal: Pass others on a narrow track. Activity: We mark a narrow track on the ground with tape (approx. 2 feet wide). Two trainees try passing each other either by overtaking or by riding the track in opposite direction without crossing the track borders. Training Goal: Master wind gusts. Unfortunately, I have no idea how to produce strong enough wind gusts without a helluva effort or random help from mother nature. EDIT: Added after suggestion from @Dingfelder: Training Goal: Improve balance and confidence when turning. Activity: Set up a slalom course using little traffic cones (cheap from amazon, ebay, etc.). Master such training courses with gradually increased difficulty and speed. EDIT: Added after suggestion from @Mono: Training Goal: Understand the importance to always ride with "soft knees" to be prepared for the unforeseen. Activity: Very, very cautious and slow ride over a prepared obstacle with completely straight legs ("locked knees"). Start with really small obstacles as the risk of injury is high. Stop the exercise when you got an impression, how fast balance is lost when riding with locked knees.
  23. Carlos E Rodriguez

    How to Fall

    Is there a way to keep this topic uncluttered? I think the forum should come up with some essential topics with minimal content that is considered essential. For example: -Protective Gear. -Learning to ride. -Learning to Fall. https://youtu.be/tUJwUUAiT4o https://youtu.be/gV2xiTodph8 -How to prevent cut-outs.
  24. Are the Inmotion devices such as the V5F and V8 UL certified? Have there ever been any reports of fires or battery explosions with their products? I've been trying to decide between a V5F+ and a Segway S1 which is UL 2272 certified, but the Inmotion website doesn't mention any sort of safety certifications. The V5F definitely has preferable specs to me, but I'm concerned about safety after seeing so many reports of hoverboard fires.
  25. Are there certain types that protect more surface area than others? Drug store therapist wrist braces seems to cover more area but do they protect the hard fall? Or should we use products designed for a specific sport, like snow boarding etc? Some of the wrist guards have splints in them. Is that a better choice? Interested to know what are you all wearing for wrists? Links to products would be awesome.
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