Xiaomi Cyber dog geared motor ~$60

This may be a potentially interesting geared motor.

From the Xiaomi surveillance device cute robot dog



That looks like a very good price for a qdd motor… thanks for sharing!


Where do they sell those motors?


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I haven’t tried to buy one (yet)

It may be China only shipping for now? https://www.mi.com/shop/buy/detail?product_id=19086

The complete dog is available on Aliexpress, so they may show up there in time.

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Ooh! I want that motor. It looks very nice to play around with for slow speed applications.

There is electronics inside the motor. Just wondering if it’s only position sensor or power stage, too?
Then there is the CAN interface, we have no idea about their protocol.
If we can make it run with sFOC and a generic powerstage, it’s a winner for that price.
But planetary gears aren’t good enough for real robotic stuff. Too much backlash.

Anyway there are some cool things it could do…

There are chinese agencies helping foreign customers to ship goods around the world, when they are for chinese customers only.
Maybe a group buy would make it cheap enough for each of us?

Not quite true! There are a lot of robotics applications where planetary gears shine :slight_smile: most of which torque transparency is needed and huge precision is not necessary

Yeah, I should row back from my strict statement. in many occasions, where gravity takes care of backlash, they are perfect.
I also made some experiments with bevelled gears for planetary gearboxes, but the gear-library wasn’t suited for such a use case.

With a weight of only 300+grams the Xiaomi motor housing might be made of plastic?
Wondering how good cooling works

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Via Twitter I got these photos of the driver.

I wonder if it’s already running SimpleFOC out of the factory…

If it’s a gd32f303 (cannot read it well), it should probably run with the stm32f1 drivers.

This guy even got vesc firmware running on gd32f303cg

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gd32f303 seems likely, annoying the photo is unclear

Searching for the engine, I found another one
I couldn’t find any information about the on-board electronics…
it’s hackable ?

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The Waveshare one does look interesting too. I wonder if it should have its own thread.

I’ve ordered 6 of these from my partner in HK.
My goal is to sacrifice one for teardown and analysis video.

Will keep y’all posted.


Yes a big thank’s :slight_smile:

Remember all the efforts put into this hardware can easily be lost if they change things, put the price up, stop selling them or whatever…

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Hence why im getting early samples. If im happy with them i’d probably get larger stock.
But i agree.

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You can say that to almost anything nowadays. We live in a fast spinning world.
I often see it as an opportunity: I never buy the “latest”, but the outdated, price-reduced version as soon as the new version appears.

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No, there is a difference. SimpleFOC isn’t going away. An open source board backed by a foundation pike the rbpi foundation like the raspberry pi pico isn’t going away. Linux isn’t going away.

Three times in the design of my fan I identified suitable motors and by the time it was time to get more they couldn’t be found anywhere any more. I gave up and insisted on buying a motor only from a reliable supplier, at 5x the price. Once with the g431b-esc1 board I was ready to get more and they were nowhere to be found, impossible to make and unsourceable. It took 2 months to get more. Even the printer filament, I found good stuff on amazon etc. and then could never get the same stuff again.

I gave up, I only buy polymaker filament now because it’s stable repeatable reliable and I know I can get more. It’s not actually any better than a lot of the other stuff I have tried, it’s about repeatability.

Sometimes you have to compromise, even using an STM32 MCU is imo a minor degree of this. They are available now, but they weren’t for a while there.

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I do basically agree. I like open hardware. The thing about this is the integrated planetary gearbox. I’m not aware of anything on the market that’s comparable. The Hebi actuator maybe, but that’s $3k

Assuming SimpleFoc will run on this driver then it will be comparatively affordable. An alternate open-hardware driver to drive this motor/gear would be great too.

I can’t spot the firmware that runs on the driver anywhere. This might be relevant? GitHub - MiRoboticsLab/cyberdog_motor_sdk