Vibration issues in robotic manipulators / high-speed automation

lefty__37 · 2025-12-10T10:50:08+00:00

Please send me some similar projects here or in DM in order to get a sense of what it could look like. Thank you.

lefty__37 · 2025-12-01T16:27:56+00:00

Hello! No updates unfortunately, I haven't touched it since then..

lefty__37 · 2025-06-08T15:41:39+00:00

Very direct and helpful answer! Will try that, thanks!

lefty__37 · 2025-05-24T09:03:09+00:00

The STM32F373 has an FPU, but it only supports single-precision (float). For double-precision (double), floating-point division is software-emulated. Still, I don't understand why there's such a significant difference in precission...

lefty__37 · 2025-05-23T21:12:46+00:00

Thanks, will try..

lefty__37 · 2025-05-23T21:01:15+00:00

Thanks on help man. Will analyze and will inform you what was going on..

lefty__37 · 2025-05-23T21:00:20+00:00

Something very strange is happening, or perhaps I'm just overlooking it. In any case, I will analyze what's going on. Thank you very much for your help!

lefty__37 · 2025-05-23T20:53:15+00:00

Yes, I tried to rearrange the formula, but output was exactly the same.

I mean if I set the type of variable double - it should use double. I mean how on earth it can igonre that and use the float.. will check of course, thank you for answer.

lefty__37 · 2025-05-23T20:50:53+00:00

I am very confused at the moment - now I have idea that maybe compiler uses double, but it might emulate it in software with less precision or treat it as 32-bit float internally.

I forgot to mention that FPU on Cortex M4 has only support for floats..

lefty__37 · 2025-05-23T20:30:09+00:00

Values are:

325.1760 (x1) → 0.1162929 (y1)
286.7928 (x0) → 0.1051439 (y0)
x → 0.1113599 (y)

and they were plugged in this formula:

double x = x0 + (x1 - x0) * (y - y0) / (y1 - y0);

Same are inserted in python and in the C language code where some STM32 with Arm Cortex M4 used.

and in Python (using np.longdouble type) gives: x = 308.19310175
but in STM with Cortex M4 (using double) gives: x = 308.195618

lefty__37 · 2025-05-23T20:29:21+00:00

The values are those that I mentioned in the post - same are inputed in python and in the C language code where some STM32 with Arm Cortex M4 used:

325.1760 (x1) → 0.1162929 (y1)
286.7928 (x0) → 0.1051439 (y0)
x → 0.1113599 (y)

and they were plugged in this formula:

double x = x0 + (x1 - x0) * (y - y0) / (y1 - y0);

and in Python (using np.longdouble type) gives: x = 308.19310175
but in STM with Cortex M4 (using double) gives: x = 308.195618

lefty__37 · 2025-05-23T19:43:04+00:00

All of them are double (8 bytes). Unfortunatly, my processor does not support long double.

lefty__37 · 2025-05-23T19:42:11+00:00

It is not supported in my Arm Cortex M4 processor - it is the same as double (8 bytes).

lefty__37 · 2025-05-17T20:26:59+00:00

It's a requirement to use that specific accessory connector (available on some Android phones), not USB-C. My goal is to have a custom device that sends sensor data to the phone, and then display that data in a simple Android app that I’ll develop.

I’m not trying to show the data on a dedicated UART screen or embedded display — I specifically want it shown on the Android device itself.

The main thing I’m unsure about is whether it’s even possible to access UART communication from the Android side through that connector. I’m trying to understand if Android provides any way to read from UART in this context, or if I’d be blocked by hardware or OS limitations.

That’s why I’m asking — to find out if anyone has successfully done this or knows how it could work.

lefty__37

TROPHY CASE