Trying to build/find a stmbl?

So I've been stuck on this for a year+ after finding the stmbl servo drive project. I have a bunch of decently powerful 220v ac Sanyo denki servos with quadrature encoders that I'd love to save from a boring fate like disassembling for fun. 

I understand the IRAM became difficult to obtain after infineon was acquired and the line was discontinued, but that it seems like one can find them from time to time for an inflated price. 

It doesn't seem like a redesign is being released any time soon. I saw talk of other alternative chips, or using similar variants that are pin compatible but with an adapter board. 

I'm to the point where I'd almost consider ordering from jlpcb and getting expensive irams, if I'm likely to actually have usable boards afterwards. I found someone that rearranged things for easy jlpcb ordering and successfully built a board and the bom runs fine in jlpcb minus some capacitor replacements, but I'm also weary of starting that process unless it truly is decently straightforward.

Any feedback on where I should start or if I'm likely to ever figure out finding a board? 

I know I can buy a proper servo, but I'm just messing around with wanting to do motion experimentation, or repowering my lathe for conversion to linuxcnc, etc. For me a kit of the time having the components will inspire the project in my spare time. 

trizno wrote:

So I've been stuck on this for a year+ after finding the stmbl servo drive project. I have a bunch of decently powerful 220v ac Sanyo denki servos with quadrature encoders that I'd love to save from a boring fate like disassembling for fun. 

I understand the IRAM became difficult to obtain after infineon was acquired and the line was discontinued, but that it seems like one can find them from time to time for an inflated price. 

It doesn't seem like a redesign isn't being released any time soon. I saw talk of other alternative chips, or using similar variants that are pin compatible but with an adapter board. 

I'm to the point where I'd almost consider ordering from jlpcb and getting expensive irams, if I'm likely to actually have usable boards afterwards. I found someone that rearranged things for easy jlpcb ordering and successfully built a board and the bom runs fine in jlpcb minus some capacitor replacements, but I'm also weary of starting that process unless it truly is decently straightforward.

Any feedback on where I should start or if I'm likely to ever figure out finding a board? 

I know I can buy a proper servo, but I'm just messing around with wanting to do motion experimentation, or repowering my lathe for conversion to linuxcnc, etc. For me a kit of the time having the components will inspire the project in my spare time. 
 

I followed STMBL for years, had some PCBs made and then the IRAM issue popped up. Last I knew there were a whole lot at Rochester Electronics but then the STM32F4's were hard to get. I didn't like the idea of using something that was already discontinued. I thought the power section was gonna be redesigned years ago but I suppose that never happened.

You can use a Mesa 8i20 but you have to handle the encoder and commutation with the controller/hal. I used one for a bit but, it's not the greatest for a spindle, probably fine for axes motors though.

It seems the STM32F4 situation is a bit better now, though? Part of my waiting a year to revisit the project was hoping something would have changed about a redesign, or some parts being easier to get.

Hm, a quick google showed the Mesa 8i20 as $240 and out of stock. Thanks for the route to explore, though. I'm just keen on the lower cost cost options. Spindle or axes, anything would be fine if I can get the motors moving and experiment.

I understand the hesitation with using something that's been discontinued, but, absent a forthcoming alternative, it seems like this is the only potential hope for random servos, aside from just buying new ones?

I also realized there was a drivers forum, sorry if this is in the wrong area.

Yeah the STMBL is a great idea. I could do alot with a drive that is easily connected over SmartSerial. I thought about taking a stab at redesigning the power board but my PCB design knowledge is best suited for things that are not likely to catch on fire.

So much work must have went into that project between the software and hardware design that it's a bit strange that it hasn't been reworked yet. It must be like 4 years now.

Hi,
I am right now building some stmbls. I do have some IRAM in spare in case you need some. 

Regards
Julian

at the meeting in april, I asked my new friends about it while they were all in the same room.

I am under the impression it is not the iram chip anymore, but another chip being out of stock, but Im not too good with the electronics lingo. It also looks like it is a side project for them, and things like dayjob/life in general, get in the way. They were all very nice though.

Yes, there are some components that are hard to find nowadays.

Right now I had problems to get the 4 ACT4088 (power supply 3.3V, 5V field an 12V field). I could order them directly from China.

A few month ago it was hatd to get the stm32F405..But today the situation is much better. So in a few days I will have everthing togehter. The 2 stm controllers of each board are already flashed.

Best regards
Julian

I have kits with the Irams and cases available as well.
 

hello!

I am looking for 3 pcs of such kits. please let me know if they are still available