4 ms·
Ok, this drives me nuts ARGH! Seriously? The STM32F103? Crazy (or should that be Craze) hobbyists using "blue pill" boards because they are cheap (and they are
by ChuckMcM 8y ago
Ok, this drives me nuts
ARGH! Seriously? The STM32F103? Crazy (or should that be Craze) hobbyists using "blue pill" boards because they are cheap (and they are, like $3 on ebay) which use this bastard chip of the ST Cortex-M line and they say "gee, its a really simple circuit and since they sell for so cheap on ebay it should be a good idea to use this chip!" BZZZZZZT!
ST Micro makes much better CPUs that would be ideal for this application, they have things like on board DSP instructions in their floating point units, and can run at internal clock rates of 180 MHz with a megabyte of Flash and 384K of RAM, some of it very high performance (core coupled memory). These CPUs are no harder to put onto a PCB than the STM32F103 and they are so much more capable. And sure, they are $10 apiece instead of $1 apiece which is fine if you're making BILLIONS of these things, but a bespoke quadcopter?
Oh but its Open Source, cool, except I can't find the PCB files anywhere, if I could I could pull out that crap chip and put in a real CPU and have OSHPark make me a few. I did find the software repo : https://github.com/Crazepony https://github.com/Crazepony and yeah, another budget quadcopter maker with a bunch of things they want to sell and an "open source" tag to try to get people to come and look. Fair enough, it made me look. It is sort of the 'freemium' hardware company model.
Sigh. I'd love something bigger than the Crazflie[1] which is like real open source (PCB and everything) and smaller than a DJI Phantom that I could play around with.
- jononor 8y agoShoot the Crazepony people an email and ask about the PCB design files for their 'open source' quadcopter?
- ChuckMcM 8y agoI did one better than that, I shot my ST Micro rep an email and asked them if they would like a open source design on the web that showcased their new STM32F4 series with built in Wireless support and their new STSPIN BLDC controllers with built in Cortex-M0s. He was quite taken with the idea :-)
- halbritt 8y agoQuadcopter pilots have been using STM32F3 for years. Check out: https://github.com/betaflight/betaflight https://github.com/betaflight/betaflight one of the more popular flight control projects. They've been supporting STM32F4 and STM32F7 for quite some time. A typical quad flight controller with an STM32F4 and a decent MPU will set you back less than $30.
- dbuder 8y agoI'm fairly certain all the blue pills that are cheap have a GD32F103 and not a ST chip.
- blt 8y agoDo you want to carry a payload or fly in wind? otherwise, I strongly recommend the Crazyflie, it is a good product with a vibrant community. It has an STM32F405 with FPU that is surprisingly powerful - nontrivial math in the fast control loop is no problem.
- ChuckMcM 8y agoI have three of them :-) And I would like something with just a bit more payload. In particular I have been fascinated by the papers on cooperative work by multiple quad copters when driven by a supervising computer vision system.
- timakro 8y agoFair enough, my first idea was actually to use MicroPython. With a megabyte of Flash that would have been possible, but 64K is just not enough.
- ChuckMcM 8y agoA micropython based flight control system would be a really cool project.
- TickleSteve 8y agohmm, watching your copter crash during Pythons garbage-collection cycle might be an issue.... Python != realtime, flight-control == hard real-time
- ChuckMcM 8y agoThe interesting difference here is that these things have a bunch of processors on them. So the 'pilot' process can be essentially an interrupt service routine that keeps things sane on an interrupt that cant be masked by the Python code. So during garbage collection your UAV might stop and hover, but it would be unlikely to crash in that scenario. Further, my experience with Micropython so far has shown it to be pretty fluid. But I would be the first to tell you I haven't challenged it all that much.
- dvfjsdhgfv 8y agoI think it's going to happen sooner that we'd expect, with the OpenPilot Revolution board being considered for a port: https://github.com/micropython/micropython/wiki/Boards-Summary https://github.com/micropython/micropython/wiki/Boards-Summa...
- justinclift 8y agoYeah, the same kind of fake "we're Open Source" seems to happen with kickstarter projects fairly often too. eg DoBot. Grrr. One place which has done it correctly though is Dorna: https://www.dorna.ai https://www.dorna.ai They kickstarted (successfully, shipping to their backers etc), now have an online store, and all of the files (both software + hardware designs) are downloadable for everyone. :)
- ChuckMcM 8y agoDamn, sometimes reading comments can be soo expensive :-)
- justinclift 8y agoHeh Heh Heh. Yeah. :)