Archived: the OG noob question thread! 😀

How-Tos & Esk8 mechanics Esk8 Mechanics
9944

Should I kill this person for not giving me their million dollars when asked for it, or should I kick the person in the nuts and run away?

Currently kicking the nuts… If I blow my load it’s your fault for not helping me. :full_moon_with_face:

9945

What’s wrong with using pla for a compression battery pack?

9946

Be really careful when considering purchasing from flipsky. Typically in this field, if you buy the cheapest stuff you can find, you end up buying it twice

1 Like
9947

My understanding is that it’s related to reluctance, and the geometry of our stators. Basically if you’ve got magnets lined up with the stators like this: image
then the magnetic field lines have the shortest airgap to cross before reaching steel again, so those magnets don’t want to move. You could even say that they’re reluctant to move :smirk:.

Conversely if the magnets are exactly centered on the gap between two stators, then the field lines have to travel farther sideways to meet steel, which “stretches” them, storing energy like a spring. Hence the magnet wants to move away from that position.

In a perfect motor with zero cogging, you basically want the magnets trying to stay still, and the magnets trying to get away from their current position, to cancel eachother out.

This is why motors with more mutually prime magnet and stator numbers generally have less cogging than ones where they have a closer common divisor.

3 Likes
9948

One way to completely eliminate cogging is to ditch steel stators altogether like inrunners do. No variation in reluctance means no cogging.

2 Likes
9949

Can anyone tell me what abs tacho is?

20200207_212920
20200207_2129201080×420 81 KB

1 Like
9950

absolute tachometer, whatever that means.

9951

It’s the number of erpm elapsed since bootup. Similar to “distance traveled” except only in regards to motor poles and disregarding gear ratios, wheel size, or wheel slippage

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9952

thanks man

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9953

my understanding is cogging doesn’t actually waste energy even when unpowered because the energy you store “compressing the spring” you get back when the “spring” releases

bldc has torque ripple but foc doesn’t

2 Likes
9954

Does uploading the new 4.1fw usually take that long?? 5 minutes in and i’m at 3.5%

EDIT : now 4.6%

9955

Over the metr module?

9956

Nope directly via usb and the vesc tool 2.02

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9957

Strange. :thinking: @Trampa

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9958

Well, who would’ve guessed…An older version of the vesc tool fixed it.

Now i need to test again if i get a bad motor detection result again. Came out of nowhere. (bldc and foc)

nope, still bad detection.

1 Like
9959

A bad USB cable could be the reason.

9960

Unrelated but i have small electronics problem.
I pulled this cable out of the… Motherboard?.. Of my speaker (minrig subwoofer 1 gen)
I don’t know what this connector is called but how do you plug it back in and which way does it go?

IMG_20200208_095603
IMG_20200208_0956032736×3648 1.03 MB
IMG_20200208_095525
IMG_20200208_0955253840×5120 3.98 MB
IMG_20200208_095514
IMG_20200208_0955143840×5120 3.41 MB

Calling speaker guys @SimosMCmuffin and @Pedrodemio

2 Likes
9961

It still happens via my bluetooth module

1 Like
9962

Just stuff it back in, it’s a friction fit. If it doesn’t work, flip the ribbon over and try again.

You may be able to look very carefully inside the connector and see if the contacts are on the top or on the bottom, and orient the ribbon accordingly.

5 Likes
9963

If you have two ESCs, use SWD Prog to reflash the device. Benjamin Vedder has a YouTube video about this procedure on his channel.