May 2, 20233 yr I have an idea for an add-on torque sensor for the BBS01 but being half retired, I don't want to do all the work. Is there anyone interested in developing this project with me? The work involves prototyping and travelling to China. If it's you, expect no pay until the project works out. I cover the expenses.
May 3, 20233 yr I suspect you'll know better than anyone else here, but don't you think Bafang have already thought about/considered/already designed such a thing? With Bafang's rich heritage of motor manufacture, robust/proven catalogue of products (including the M series with that torque sensor), they must have something up their sleeves. The whole BBS thing, bullet-proof and highly successful though it is, is a little long in the tooth now. They've got both the existing/proven technology and manufacturing ability to do it - and could easily reduce the size and weight too I don't doubt. Do you think there's just some tactical reason as to why they haven't actually launched such a thing yet?
May 3, 20233 yr Author thank you for replying. Maybe more members want to join in after your post. I suspect you'll know better than anyone else here, but don't you think Bafang have already thought about/considered/already designed such a thing? With Bafang's rich heritage of motor manufacture, robust/proven catalogue of products (including the M series with that torque sensor), they must have something up their sleeves. yes, I am sure you are right on this. They must have already got something like this knocking about in their product development team. If not, they can easily do something 10 times better than what I am trying to achieve. But.. Would they consider to make a retrofit part though? I think they would release instead a new version under a new designation, something like BBS01Torque for example. Manufacturing wise, it is better to redesign the whole kit instead of modding/adding. Do you think there's just some tactical reason as to why they haven't actually launched such a thing yet? I reckon it's because their market share has never been threathened, not by tongsheng, not by any other company in China. They are the biggest and best, and it's not me who is going to change any of that.
May 3, 20233 yr Author I intend to replace the main gear shaft of the BBS01/02 with another that incorporates a torque sensor. To reduce interference and ensure repeatability, the sensing element will be an in-house formula for a magnetoresistive compound and instead of pickup coil, it will be just ordinary contact brush. Alternatively, I would investigate a method of embedding an off the shelf strain gauge inside an off the shelf polymer. The idea is simple and low cost. All critics are welcome. Edited May 3, 20233 yr by Woosh
May 3, 20233 yr Man, a TS retrofit for those Bafangs would be far out! IMO Finding a partner to believe in the profitability of this project to invest as much as you will be a toughie tho. Dragon's Den? Could be fun! Edited May 3, 20233 yr by lenny
May 3, 20233 yr I reckon it's because their market share has never been threathened, not by tongsheng, not by any other company in China. They are the biggest and best... History shows Bafang don't rest on their laurels. Wasn't it ES who discovered a more reliable hall for their BBS (patchy memory here)? Bafang listened, changed, adopted it. I doubt development of the M series was driven by any fear of threat from competition, rather that they could so they did. Business wise BBS/2 is long overdue. Maybe they're waiting for the froth of these newcomers/upstarts to fizzle out before they launch something that comprehensively slaughters them! Maybe you could take (sell) your idea directly to Bafang, or for a royalty, if they bite?
May 3, 20233 yr Author Wasn't it ES who discovered a more reliable hall for their BBS (patchy memory here)? FETs I think. They changed them to IRFB3077 FETs with model B. Maybe you could take (sell) your idea directly to Bafang, or for a royalty, if they bite? ha ha ... in my dreams!
May 3, 20233 yr In the event that you do find someone to work with you on the TS, what about the software development angle? (I'm assuming the signal from the TS needs to work with the OEM formware? Given how long and the number of iterations in the development of OSF for the TSDZ2, that's a long path to tread. Maybe one of the TSDZ2 OSF fdevelopers from ES might be interested?).
May 3, 20233 yr Author I will write the code for it, similar to the code I wrote for that guy who tried to add a throttle to his HESC suntour bike sold by Halfords. I can do that with the arduino or ESP32 or one of the new RISC V. The coding won't take long. I break out the PAS and throttle signals and use the torque sensor to drive it. There is no need to change the Bafang firmware. The achilles heel of the project is to sort out production if the prototype works well. The smaller the production cost, the higher the financial risk. Edited May 3, 20233 yr by Woosh
May 3, 20233 yr I have two questions 1. Are you looking for someone to fly to China to oversee the manufacture of samples, eat Chinese food, and bring prototype sensors back? 2. Are there badgers in China? p.s. My titanium wrist is very strong. Edited May 3, 20233 yr by I893469365902345609348566
May 3, 20233 yr Author yes, something like that, although for prototyping, we can do mostly here, up to pre-production samples. After that, we'll need a good Chinese partner to take over the project.That's when going to China is necessary. If this project works out, I have an idea about a new cycloidal gearbox for bottom bracket motors...
May 3, 20233 yr Sounds like you need someone who knows all aspects of the technology and it's manufacture, who is also a great communicator and collaborator, with a very strong titanium wrist for heavy lifting. I'll throw my hat in the ring, if you can't find someone with a titanium wrist. I like Chinese food. Edited May 3, 20233 yr by I893469365902345609348566
May 3, 20233 yr One only has to look at the Lingbei mid drive ( ex Bafang engineers) the motor barely got off the ground and it sank without much trace, though some time ago I thought I sa wit on Aliexpress . It wasn't easy to fiind.
May 3, 20233 yr I gave up on the BBS after having two controllers go wrong and barely 3200 hard miles on the clock for the pair of them, that was after the fiasco that Tony had with GSMoon drives. My two drives were pretty useless and both failed in fairly quick time , In total only managing a paltry 320 odd miles for the pair of them. The TSDZ I have , Iam hoping it bucks the trend of those two experiences.
May 3, 20233 yr Author I gave up on the BBS after having two controllers go wrong and barely 3200 hard miles on the clock for the pair of them, that was after the fiasco that Tony had with GSMoon drives. My two drives were pretty useless and both failed in fairly quick time , In total only managing a paltry 320 odd miles for the pair of them. The TSDZ I have , Iam hoping it bucks the trend of those two experiences. BBS01B had practically all the early issues sorted. Controllers got better FETs. water seals fit much better. It's rare now to come across a rusty BBS01B. The GSMoon was a disaster. The controller and LCD were not up to scratch. Since, I never want to be first in line for anything.
May 4, 20233 yr I will write the code Write the code first to try using modelled or recorded torque data to see if it's a viable enough an idea, before developing your torque sensor? It'd take longer to chop away badger collision titanium wrist guy's handcuffed hand with a machette, to steal a briefcase containing your trade secrets at Shenzhen airport. That's a big plus. Edited May 4, 20233 yr by guerney
May 4, 20233 yr It'd take longer to chop away badger collision titanium wrist guy's handcuffed hand with a machette, to steal a briefcase containing your trade secrets at Shenzhen airport. That's a big plus. :eek::eek::eek::eek::eek: !!!!! I don't want to go to China. Edited May 4, 20233 yr by I893469365902345609348566
May 4, 20233 yr The best option for the GSM was that which Tony aka anotherkiwi did, use it wih a KT controller . He had good success using it that way.
May 5, 20233 yr Great quality accurate torque sensors wouldn't be needed for: https://www.pedelecs.co.uk/forum/threads/has-anyone-heard-of-or-tried-toseven-mid-drive.44959/page-26#post-679582 Edited May 5, 20233 yr by guerney
May 5, 20233 yr [mention=6303]Woosh[/mention] - I posted that there: https://www.pedelecs.co.uk/forum/threads/has-anyone-heard-of-or-tried-toseven-mid-drive.44959/page-26#post-679582 ... because I've noticed Endless Sphere... technical masturbators ... tend to not visit any other thread. Edited May 5, 20233 yr by guerney
May 5, 20233 yr Author I like ES but their interests are mainly on how far they can push. I'd lose all my hair worrying about replacing kits under warranty.
May 6, 20233 yr Author In the event that you do find someone to work with you on the TS, what about the software development angle? (I'm assuming the signal from the TS needs to work with the OEM formware? Given how long and the number of iterations in the development of OSF for the TSDZ2, that's a long path to tread. Maybe one of the TSDZ2 OSF fdevelopers from ES might be interested?). I ordered the parts (arduino, strain gauges + HX711, bottom bracket axle). I will have to source the slip ring later but for bench testing, I don't need the slip ring. The parts will be here in about 10 days-2 weeks. Will post the result and pics here when it's done. In the mean time, I will design the PCB to keep the all the electronics together.
May 6, 20233 yr If it turns out that only somewhat woolly power application is possible utilising the throttle control, not precise enough, you could try the Guerney SCEPTA™ - System Cadence Enveloped Power Torque Assistance, as I desrcibed in the post linked below: https://www.pedelecs.co.uk/forum/threads/has-anyone-heard-of-or-tried-toseven-mid-drive.44959/page-26#post-679582 In my mind, this would provide distraction-free bike operation traversing hilly terrain, enabling the cyclist to better focus upon enemies. Worry that only woolly power application would be possible, was another reason why I linked to Guerney SCEPTA™ previously in post #20. Also why I suggested writing the code first, to try driving the throttle control in post #17 using modelled or recorded torque sensor data. _________________ EDIT: For convenience I've copied that post linked above and pasted below: Making an effort cycling is something I can't do anymore, therefore I like the Bafang BBS01B's cadence sensored operation, which enables me to pedelec for many miles despite being old and unfit - doing so makes me feel like the Superman I (never) was in the 80s. The other advantage is, I don't turn up to work sweaty in need of a shower. However, your mention of your sliding speed control is interesting - sorry, I can't find that post of yours to link, where you also mention you'd like to use a slider strip to control current next time. I assume you were using a KT system. A simpler automated system to increase current at the detection of increased rider effort might be useful and highly desirable for some. A couple of years ago and the year before that, I suggested that a TS system could be added to the Bafang BBSXX(X) series, suggested using a somewhat clunky method: https://www.pedelecs.co.uk/forum/threads/what-is-the-bafang-bbs-pedal-assist-algorithm.43131/#post-647914 ... Because I'm rather lazy and don't have time to do unpaid programming, I posted that in the hope that someone other than me would take an interest and make available something I could simply buy, and because a torque sensored BBS01B kit isn't something I actually want or have any need for. I also wrote something similar with the same intention the year before under a different username, and I requested the deletion of that username and account by admin, because at the time I found this forum too interesting. Meandering back to the system I wouldn't mind trying using at least once: Cadence sensored with current set at the cotroller via the PAS buttons 1 to 9 (6% [the minimum required to overcome motor resistance, plus a bit] to 100% of say 15A in 9 increments, with 100% keep current for every level), then automatic increase of motor current (except at level 9) using the throttle wires on the BBS01B, upon detection of more torque being exerted by the rider - the more micro than usual microcomputer would detect increased rider effort using a torque sensor of some sort. Current would increase slowly after n seconds (a user changeable variable) of continuous detection of increased effort, using the control input intended for the throttle, and would reduce power over a couple of seconds after detected rider effort is reduced (the power envelope would be user changeable). Ebrakes could be used to stop power at any stage. Fast responsive accurate control using good and expensive torque sensors wouldn't be necessary for what I have described. The Bafang controller's firmware would need certain settings, but no wholesale rewrite of the configurator would be necessary. While riding, one would simply experience more assistance being applied automatically when going uphill or traversing uneven terrain. Too much/too little assistance? Use the +/- PAS buttons (if throttle power is limited to PAS current levels). And the rider wouldn't experience a sudden unexpected huge dangerous increase in motor power triggered by potholes or rocks. Because it's firmware is open source, I also see this possible for the TSDZ2. Again, I'm hoping someone other than me will make something I can simply buy, because I'm lazy and am gleefully happy with my BBS01B's operation, after firmware setting fiddleage. Edited May 6, 20233 yr by guerney
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