Recent submissions

Comment · 4 days ago
Invert the process - That would allow you to build a thickness gauge from just white light and 3 sensors. Or maybe add a few more (there are multislectral sensors from ams osram) for robustness.

Not sure why you would need that though..

Similar effect in devices to measure polarization of light. You introduce white light and crossed polarization filters. Depending on the amount of rotation similar colour patterns emerge. I haven't seen an automatic device yet, but manual evaluation of the colors

Comment · 4 days ago
Even deeper - go have a look at the huge catalog of basic parts of jlcpcb. There is no procurement process and delay needed, those seem to be already on the shop floor or maybe even on a feeder of a pick and place machine!

The integration of lcsc is incredible.. let's see how they beat this in practice

Comment · 8 days ago
If we look at the example of the FFT blur filter, sure O(n) looks easier and independent of the blur size, but you have an overhead in needing FFT and iFFT. It can be faster for some sigmas, but not for all. So you need different variants depending on sigma and a smooth transition between them.

Then you can start approximating - for large sigmas just using every 10th pixel would work. Looks like MS Teams background blur is doing this, you get a blurry background with aliasing - yay!

Once you add SIMD variants and look at CPU caching behaviour, you build versions for different CPUs. Instead of filtering the whole image for one dimension you might finish blocks locally.

You've now got a dozen variants that need testing and maintenance on different architectures.

I'm reminded of my colleague preaching requirements engineering - what was the goal gain?

Comment · 22 days ago
Well.. it sounds like they want to "avoid bulky VR headsets"

But their alternative is even bulkier. A chair with a big screen, more like a personal holodeck box to sit in.

I totally believe this can be used to place better optics and avoid motion sickness, for better immersion.

The product vision is not clear for me - maybe as a better version of the single person privacy phone booths that can be found in shared office environments? At home? Rather not

Comment · 1 month ago
It is still going to be many amps.

The capacitor circuit has the advantage that could can't mis-drive. If a transistor of the half bridge stays turned on for longer than the msec required, nothing will happen. The half bridge chip (usually) already prevents that both transistors are enabled at the same time. This is great when you develop firmware and might end up with one pin staying high for too long.

With a direct drive, the flip dort magnet wire could quickly burn through if you leave half an amp for too long.

Comment · 1 month ago
Oh - but only touching them?

I was hoping for an iteration of a factorio belt that could actually move!

Comment · 1 month ago
I can imagine the other internal teams looking at this.. "100 TB gets you attention? Hold my beer.. we will try that as well!"
Comment · 2 months ago
I'm puzzled as there seems to be a clear pattern on how a human user would look like vs a bot.

High bot likely hood if: If a session jumps to a different ip. If the session jumps IP after just a few requests. If a new blank session starts with a deep link. Maybe those are cases where some POW is better justified?

Assumption: the rendered HTML might be viewed by a legitimate developer, even via a deep link from outside. But rarely from a wget script without a session cookie .

The other nice idea from the comments - is this rendering effort something that can be pushed to the user? Instead of pointless POW work, can you offload the expensive rendering to the user side?

But certainly, this is just an armchair comment and the kernel guys certainly have tried everything in this arms race...

Comment · 2 months ago
This hints at a hiking trip planner maybe? Depending on time of day and year evaluate a path to be in the direct sun/shade?

In summer, I might want to avoid the direct sun. Suggest the hiking path with least direct sunshine. And if it is autumn already, then please suggest a hiking path to be in the sun all day.

Might be a cool feature to compare hiking paths by percentage of direct sunshine.

But maybe, selecting a path through a forest vs. across open fields might already do.

Comment · 2 months ago
Great result - it would be nice to learn how this could be used..

How would you connect a Tamron lens to a Linux machine? Is this with the external USB port or Bluetooth dongle? Or through the bayonet connector? A linx camera controlling it's lens?

Just for settings and firmware update? Or some imaging workflow? Can you give a practical example of Linux also controlling the camera?

Comment · 3 months ago
I think this is a clever idea.

A hub motor for each leg adds some weight, but you get a rolling mode on flat terrain with great range.

At the same time you keep obstacle climbing mode with stationary wheels, and can use the leg actuators as shock absorbers and obstacle avoidance on a bumpy path. Best of both worlds, with a new software challenge.

Comment · 3 months ago
I tried to think about difficult ways to compute the high frequency coefficients to work from the "wrong" coefficients of the first image...

But this is clever - just smash them together. Low frequency of one image concatenated with high frequency from another. This works surprisingly well!

Comment · 4 months ago
Both your points hold.

The distinction is rather that the device was made next door, from raw materials, with them possibly watching. Certainly acknowledging the craftsmanship, but still while understanding your tools.

Today, labs are filled with expensive machines and you are not able to peek inside. You need something? Only from a catalog, made in a mystical factory, without you knowing what's inside.

This abstraction speeds up your process (the tool you bought is fully qualified for what you plan to do) but also detaches you from the low level inner workings. Kids are fascinated if you take an everyday object apart with them (but maybe only if it was already broken)

Comment · 4 months ago
The linked article is a high level announcement that new sensors were installed, but no experiments yet.

I would have loved if they shared some technical details, e. g. which sensors, how does it record, frequency range and sample rate, time synchronization, offline capabilities. Maybe even a photo of the sensor? (I couldn't find any)

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