DD Motor

[mxlemming]

I'll buy a motor if you ever actually make something but at the moment, you are asking for donations for nothing tangible and you haven't even published your name, have no company behind it, haven't made any effort of your own so far and don't appear willing to put your own money up.

Motor development might be a bit costly, but you could have a prototype for a few kUSD for which you don't need 250x50$.

I'm calling scam until you actually make something worthwhile off your own back.

 

[hillzofvalp]

removed

 

[hillzofvalp]

removed

 

[Woly]

cause I'm not going to do another crowdfunding campaign putting the risk on backers which is too stressful).

Getting donations from this forum is still crowdfunding.

 

[hillzofvalp]

Yeah, it is, but not in the conventional sense as no “rewards” are present. The closest resemblance I guess is gofundme, which is a form of crowdfunding but I don’t think usually associated with research and development of a product.

If it’s not something people from this forum want to be involved with, I understand. But it seems some people went through the survey and support the idea, I’m sure some people will not. What are the rules pertaining to this.. let me see. Is this considered commercial activity? If so, can a moderator move it to marketplace or to off topic.

 

[The Toecutter]

If I lived near LA, I could actually provide assistance, but alas. I have experience as an electrical engineer.

If I had the cash, I'd do exactly what you are talking about doing. If I get the free time, I may give building my own crude motor a go without all of the fancy equipment, as Cedric Lynch did in his youth. It would only be a proof of concept and probably not usable, but it would be a start. The control system for the type of motor I want is going to be the REAL job.

 

[hillzofvalp]

If I lived near LA, I could actually provide assistance, but alas. I have experience as an electrical engineer.

If I had the cash, I'd do exactly what you are talking about doing. If I get the free time, I may give building my own crude motor a go without all of the fancy equipment, as Cedric Lynch did in his youth. It would only be a proof of concept and probably not usable, but it would be a start. The control system for the type of motor I want is going to be the REAL job.

I'm actually not in LA very much.

What is the motor that you want? some kind of distributed inverter dealio..

 

[The Toecutter]

What is the motor that you want? some kind of distributed inverter dealio..

Something like this:

https://endless-sphere.com/forums/viewtopic.php?f=34&t=64509#p968031

...but in a hub motor design that can fit a bicycle cassette or freewheel on it into 135mm dropouts.

The four self-developed AMZ M7 wheelhub motors deliver 38.4 kW each at a weight of just under 3 kg. A staged planetary gearbox transmits the motor's torque, resulting in 375 Nm at the wheel. Thanks to an advanced vehicle dynamics control including torque vectoring and traction control, the ...

 

[thepronghorn]

I guess you're still looking for feedback, but what kind of motor do you think you can improve on?

Just a halbach array, how much will it help? I think it reduces weight a bit since you can use a little less magnet and don't need back iron although you still need something stiff to hold the magnets.

I think the bigger gains are to be had from format changes i.e. larger diameter. The problems there involve the spokes getting quite short unless you go the bionx d500 route and put the motor between the spokes which limits your motor width. The d500 also had trouble with the side covers making a fair bit of noise.

 

[qwerkus]

I guess you're still looking for feedback, but what kind of motor do you think you can improve on?

Just a halbach array, how much will it help? I think it reduces weight a bit since you can use a little less magnet and don't need back iron although you still need something stiff to hold the magnets.

I think the bigger gains are to be had from format changes i.e. larger diameter. The problems there involve the spokes getting quite short unless you go the bionx d500 route and put the motor between the spokes which limits your motor width. The d500 also had trouble with the side covers making a fair bit of noise.

The d500 is overrated. You can get the same results with a smaller rh212 that costs a fraction and is much more diy friendly. Diameter is not everything; proper stator width copper fill more than make up for a smaller diameter. Sure the 212 weights almost 2kg more than a d500, but that extra weight comes handy when trying to avoid overheating.