Jump to content

Open-source EUC motherboard


Inductores

Recommended Posts

So it actually uses the exact same mcu as the blue pill board? I went through the thread again and saw that you posted it earlier... :unsure:


I found a nice pinout diagram (see below), but I can't find your schematic of the rockwheel anywhere. Can you post the schematic? 
I have received all the parts from your parts list except for the ST-link... So I can't program the stm32 yet. I ordered a few new ones from aliexpress so hopefully they'll be here soon. I'm going to the library today to see if I can find any books about motor control algorithms. And I'll solder on all the pins for the dev boards.

Do we need to create a waveform with the built-in DAC or does the circuit board provide its own DAC? Or are we using some digital square wave stuff like pwm?
stm32f103c8t6_pinout_voltage01.png

  • Upvote 1
Link to comment
Share on other sites

33 minutes ago, h3X said:

Do we need to create a waveform with the built-in DAC or does the circuit board provide its own DAC?

I'd see no need for a DAC. Maybe for sound output?

33 minutes ago, h3X said:

Or are we using some digital square wave stuff like pwm?

Yes. Imo one has to be carefull with the startup procedure, so the three used outputs are from the beginning on in a valid state so the mosfets are not blowing up! Could/should be solved in hardware - but maybe one has to write a one bootcode? ... Don't know the stm32, but should be worth to check the start up sequences....

  • Upvote 1
Link to comment
Share on other sites

On 6/12/2019 at 11:47 AM, Chriull said:

Yes. Imo one has to be carefull with the startup procedure, so the three used outputs are from the beginning on in a valid state so the mosfets are not blowing up! Could/should be solved in hardware - but maybe one has to write a one bootcode? ... Don't know the stm32, but should be worth to check the start up sequences....

The pins are inputs after reset: "During and just after reset, the alternate functions are not active and the I/O ports are configured in Input Floating mode (CNFx[1:0]=01b, MODEx[1:0]=00b)." ( https://www.st.com/content/ccc/resource/technical/document/reference_manual/59/b9/ba/7f/11/af/43/d5/CD00171190.pdf/files/CD00171190.pdf/jcr:content/translations/en.CD00171190.pdf  9.1.1 General Purpose I/O (GPIO) ) 

If (and likely when) there's a separate gate driver for the mosfets, the gate inputs are probably pulled down by some resistors to keep the mosfets off, otherwise while the other ends in the MCU's are also inputs (high-impedance state), the floating line might pick up interference and randomly turn on the mosfets? Might be also that the gate driver itself has internal pull-downs.

Edited by esaj
  • Like 1
  • Upvote 1
Link to comment
Share on other sites

I would like to contribute to this exercise, although I am looking for a Onewheel-type form factor.  I am fine on the electronics assembly and hardware build, just lack a bit of coding skill (I can hack about well enough).  Keen to watch this develop.

Link to comment
Share on other sites

Currently troubleshooting connectivity issues with the st-link. If my experience is something to go by, nothing ever works like it should out of the box. Especially in electronics and programming!

I ordered several st-link dongles when I was buying stuff, so hopefully this is just a one-off defect. If not maybe I'll just start coding on another platform instead.

Link to comment
Share on other sites

I'm thinking about getting the schematics from a Ninebot One S2 (mine). The problem? Multi-layer board and (probably) need to destroy the board to access to the inner layers :(

Does anybody have a Ninebot One S2 damaged board just to test?

Edited by Inductores
Link to comment
Share on other sites

Today I learned that Alien Power System is offering ESCs up to 450A 24s (88.8v nominal/100.8v at full charge). Here's a moderate example at 300A which is more affordable (£209). This should work for EUC and may be better than a completely new design. APS also offers custom ESCs.

  • Upvote 1
Link to comment
Share on other sites

Update: I bought a broken rockwheel gt14 and I'm planning to test drive it with a third party speed controller (vesc). This means I have a (broken) motherboard to mess around with.

  • Upvote 1
Link to comment
Share on other sites

  • 1 month later...

Sorry, I didn't provide any info for almost two months... but I'm planning to program it by myself using a FPGA. Just saw a paper using one:

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=2ahUKEwi2mtb046LkAhVCDuwKHS7mAWEQFjAAegQIABAC&url=https%3A%2F%2Fwww.mdpi.com%2F2079-9292%2F8%2F2%2F198%2Fpdf-vor&usg=AOvVaw0IquFUWfvusVHp1WeGwe3z

I have to do the board layout, but first I need to define all the schematics...

Link to comment
Share on other sites

Just now, h3X said:

I have gotten the motor running with vesc but I wired the Hall sensors wrong so I only ran it in bemf sensing mode. Do you know vhdl Inductores?

I learned some VHDL some years ago, but just the basics... I was thinking about using icestudio:

https://github.com/Jesus89/icestudio

Link to comment
Share on other sites

FPGA is a pain. Don't use it unless you absolutely have to.

There is no need for VHDL in a unicycle. :-) STM32 with ADC + interrupts + RTOS is more than enough.

Or you can do it like InMotion: Two STM32's - one for low-level stuff (engine), one for high-level stuff.

Edited by atdlzpae
  • Like 1
Link to comment
Share on other sites

All the blue pills I bought from China were shit (or the st-link dongles were), so I haven't gotten any closer to programming it. I have found my old box of microcontrollers and can choose between an old Arduino, a TI msp430, or a raspberry pi 3. I have a bunch of mpu6050's so I may as well start reading sensor data and develop a balancing algorithm with one of these dev boards...

The vhdl class also includes arm assembler and optimizing an FFT algorithm so it would probably be great for motor control, but I have other more important classes for now so I'm postponing that... Still down the line I'm doing it so it probably makes sense for me to choose a board with an arm processor at least. 

One of these days I'm going to rewire the Hall sensors and test my motor with a bench power supply that can deliver more voltage than my battery pack, and maybe I'll post a video when I get it running.

Link to comment
Share on other sites

  • 2 months later...
On 11/2/2019 at 2:09 PM, Attila Demeter- Szatmári said:

Hi guys, 

Please watch this:

This guy reflects to another engineer who made a firmware to the open source vesc 4.12 hardware which can be used for an euc I think. Can you have a look at it? 

 

If you could post a direct link that would be great. I don't use Instagram.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...