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About trevmar

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  • Birthday 11/14/1948

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  1. I trimmed the bluetooth antenna on each of my MiniPROs so that the effective range dropped to around 6-10ft. Enough to get a signal for the rider's cellphone, not enough for a bystander to interfere with the operation of the MiniPRO, or even scan your presence. The antenna is cut in two places, as shown on the photo. I used a Dremel tool, you could also use a carbide scriber. One cut isolates the chip from the resonant element, the second de-tunes the zig-zag resonant element itself. Anytime you want to re-instate the full Bluetooth range just (carefully) cover the cuts with a blob of solder
  2. I had a bit of trouble getting connected initially. I connected using the Segway app, then opened the battery app, and all was OK. Closed the Segway app and battery app still stayed connected. Bluetooth is like that, sometimes...
  3. The MiniPRO battery packs are configured as 15x2 cells, for a total of 30 cells. The cells used are either MG in the original MiniPRO battery pack or MF in the reduced power lower cost variant. Both are rated at a maximum continuous current delivery of 10 amps max. Two identical cells of each are selected at the factory, welded in parallel, then they are stitched into a series bank of 15 twin-cell 'cells'. If one of the individual cells goes fully faulty then the other cell will have to deliver all the peak motor current, which according to the Engineering blog, is normally 10-15 amps. This will give problems, so a single cell failure will degrade the current output of the whole battery pack. The problem is that the cell voltage is not an exact measure of the state of the battery. One cell of a pair could be totally dead, yet the remaining cell could put out a correct voltage. It would be the current which would be halved. This is why there is such a complex BMS on these battery packs, to try and reduce cell failure. I built my pulse-current tester so I could throw a 20-25 amp load across the battery pack and make sure it could supply the full current. Details are in this thread: https://forum.electricunicycle.org/topic/10991-minipro-batteries-4300mah-or-5700mah-boondoggle/?do=findComment&comment=189387 Having played with lots of these 18650-size batteries over the years, I would not become worried until the discharged voltages varied by more than 0.1V and even when this happens I would suggest trying to assess whether the battery is able to supply full motor power, as it may well still be able to do. I am sure the BMS and the main firmware measure maximum motor current, but AFAIK there is no way to get a readout from them of how much current they are seeing from the cell-bank. However, being able to watch a single two-cell 'cell' of the battery gradually change with time is far better than having no idea whatsoever of what is happening inside that battery
  4. It's not too bad. But there is a gunk covering it for water-protection that will have to be removed, and getting the chip off without harming the traces under the chip is going to be a challenge. But LQP64 is usually OK with an air-gun and soldering iron. I cheat by using a low-temperature solder paste when mounting these packages to an already soldered board, and I usually snip off the leads to the current CPU before desoldering (this protects the PCB traces). So there will be no going back for me...!!
  5. Whenever anything like that happens to me I stop, take off the knee-bars, tip the minipro upside down and do a factory recalibration to get rid of any stored values about previous riding. Once I had a bad accident, and the machine was on its side beeping away for a minute or so. We couldn't ride it at any decent speed after that until the memory of that event was erased by this recalibrate procedure...
  6. Can you give us progress info on Swallowbot, as neither Alexei or Alexander seem to be posting progress here. If we buy the programmed motherboard, how uo-to-date will the Swallowbot on it be? How will we upgrade that version when improvements are made to Swallowbot? I am particularly interested in progress on this item listed on mimod.ru's Russian language Swallowbot page, and not its English page. It is: "- remove the penalties for speeding and driving over bumps at all (warning of excess power and short-term penalties for this will remain, is not safe without them)" I would guess that penalties for "excess power" are killing me on the hills. Pushing back at 11Km/h is really hard for me to adjust to. When I ride slowly it tends to occasionally surge to 12-13Kph, and being tipped back all the time is really bad news on a hill (sometimes hard to retain your balance). The speed is even lower once the battery gets to 50%... And what is this about a penalty for riding over 'bumps'?? Ninebot should have realized that is often not under the rider's control...
  7. If you have a spot-welder it is a straightforward job to put new LG battery cells into the pack. You should be able to match the batteries into pairs using the cells' series resistance, which is easily measured.
  8. Yes, something is not right. I have been waiting for somebody to give me comparative speeds up hills (I started a topic on that) but nobody else seems to be operating in a hilly environment. All I can do is compare the four units I (and my wife) bought. At least we got them at a good price (the two NM320 were factory refurbished). They all behave the same, except that two are not to the 50Km mark yet, and this has been a problem. We will now make sure they all get to the 50Km mark before doing any more riding (it is a challenge to find a flat surface to run the miles safely, but a local main road does have bicycle tracks, I have been using that). We got trapped at low mileage as both of us were thrown at the 2cm ledge at the bottom of our driveway. so we have only been riding infrequently. I was thrown so badly the first time we rode in our local park that I couldn't walk for a week, and comfortable walking took over a month to come back. It's 3 months on now, and I am able to ride comfortably now, but I am spending most of my time making sure I understand the safety issues with the MiniPRO on hills, because it is only marginally safe up and down our local streets here, typically beeping/pushback at 8-10Km/h up and 18Km/h down. Later on we will try off-road again... Hardware tweak is to drop the PWM motor-current-sense resistors on the mother board to 67% of their OEM value, and see what parameters of the ride change. That change should increase the maximum current being fed to the motors to 150% of design max, and thus reduce the safety margins the engineers designed to protect the battery pack. That's fine, however, the current is still within battery spec. I have tested my batteries thoroughly, and will keep a very close eye on them while they age. In any case, maybe I will only need 20% or so, I won't know until I try it... (Alexei apparently overpowers the motor in his M365 firmware).
  9. Sadly, the sellers of tyres these days can't give you any specifications, you just have to buy and inspect the damn things... I sometimes wonder whether even the manufacturers of these small tyres know what they are doing.. They don't put the 2-Ply or 4-Ply rating in their ads anymore, and Heaven help you if you are trying to figure out an optimum inflation pressure! We were taught all the theory on pneumatic tires at Uni (many years ago) and so it is harder for me to accept second-rate 'solutions' to this most important part of a transporter's design :)
  10. Thanks FreeRide and IRK. The problem I am having is that the roads in my vicinity are very steep, even the off-road dirt tracks, and the MiniPRO really is having trouble staying upright on them. When it gives up it cuts out, throwing the rider's weight forward, and then a few seconds later starts again and runs into the riders feet (or body, if you have fallen over). The MiniPRO were unusable until activated, and dangerous during the first 50Km, but seem to be much more stable now. But I am going to try a hardware tweak to give the motors more peak power, just like Alexei does with his Xiaomi scooter software, trading hardware safety for rider safety :) Will report what I find...
  11. There is a new app on mimod.ru, 'NINEbattery v1.6' that you can freely download for Android: https://mimod.ru/en_US/ninebattery/ This a MUST-HAVE for every MiniPro (or ninebot scooter) owner, because it shows the status of EVERY CELL in the battery pack (actually, in the miniPRO the cells are two paralled LG cells, the combined voltage is shown). No longer do you have to wait for a battery pack to fail, you will be able to see weak cells before they get bad enough to make your miniPRO fail (and throw you). I tried it on both my N3M320 and N3M260 models, screenshots below. I found some difficulty connecting with Bluetooth, but bringing up the Segway app talking to the miniPRO, then killing it and bringing up NINEbattery, seemed the most reliable way to get a Bluetooth connection. Internet connectivity is not required. Many thanks to Alexei and Alexander for this wonderful addition to my toolbox!
  12. I just reached the "run-in" 50Km of one of my new N3M320 MiniPRO by riding it around the block continuously for several hours. I noticed a small speed increase before push-back, and when I went to my 1-in-8 test hill I confirmed that tilt-back speed had increased from 9Km/h to 10.5Km/h (approx). Both my run-in MiniPRO are both doing the same speed on that test incline now It isn't fast enough, IMO. Not compared with the data given by the Ninebot engineers in their blog. They say: "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" yet here I find that a 94Kg rider on an 800W MiniPRO climbs 6.5 degrees at a maximum 10Km/h before pushback. My slope is 1-in-8 rather than their 1-in-4, my rough maths say that something is still being throttled back in my 1.1.9 firmware.
  13. Both Alexey and Alexander are doing an amazing job! But the $200 I am about to spend to get Swallowbot mostly goes to the motherboard supplier, not to them. As for security, they themselves have cracked Ninebot's security, of course somebody is going to crack whatever Swallowbot puts in place! The key thing is to be visible in the community, so that the $200 I will need to pay to get Swallowbot goes fully into their pockets. Additionally, few are going to pirate their firmware if they continue to make improvements. Buying it is an investment in our collective future. Yesterday I was installing a new version of the Segway Android app in my phone, and it asked me to confirm that it was to be used in the USA region. I was just thinking maybe the app signals the firmware in some way to turn on the restrictive rules that are making my MiniPRO such a pain, by comparison with the Russian videos! Is Swallowbot going to perform the same when talking with a USA app as when talking with a Russian app? There do seem to be Geographic factors in the app....
  14. Yes, it is amazing what some MiniPRO will do. But none of my four MiniPROs work as well as that, even with firmware 1.1.7. There is no way they could be coaxed to perform that well. Mine cuts off and throws the rider forward from the 1" bump at the end of our driveway. I was thrown forward from a single 1" pebble on a well-kept dirt road and badly twisted my ankle. I think that the "safe" firmware sold in the USA is greatly reduced in peak power. I am hoping that Swallowbot will give me at least the same performance as Ivan demonstrates But I have no idea if it will. No specifications have been published, Alexander has not even described exactly what Swallowbot does. That would be far more valuable than a video
  15. I use the No 2 tires, mine are branded "Fuiben." Note that these tires are directional in soft dirt, as the outer tread forms a "V" shape which should have its apex in the direction you are travelling. The photos above show this tread. The Innova version of these tires is non-directional, as the outer tread does not form a V. On asphalt it makes no difference, as only the central area of the tire contacts the road. They have an excellent grip, and are softer than the OEM tires,, soft enough to handle small obstacles well. I use them at 15-25psi. Unlike my knobbly Innovas they run very smoothly and quietly, as Kirill says I rode up within 6ft of a rabbit the other day.. Yes, I know this is a bit off-topic, but nothing is happening on the "Russian Hack" as far as I can see. No details on what is supposed to do have been posted, just the videos... We need some reviews, please... (I am especially interested in hill-climbing ability)