sadhorse (u/sadhorse)

sadhorse commented on Strain gauge made out of PCB github.com/vapetrov/PCB_s... · Posted by u/dr_coffee

For a long time I've been trying to make a DIY milligram-accurate scale, and milligram-accurate strain load cells are expensive. Does anyone know if the resolution of this is high enough?

sadhorse · 4 months ago

Use vibration to measure small masses. Measuring natural frequency can be very accurate and sensitive.

sadhorse commented on Berkeley Humanoid Lite – Open-source robot lite.berkeley-humanoid.or... · Posted by u/ratsbane

MoonGhost · 4 months ago

Thanks, but no. It's going to be robotic arm with gripper and camera. The rest can be either Raspberry Zero (for cam, control, with net or blutooth, something big for high level). Another option, not exclusive, NVidia Jetson Nano instead of Zero. It could be Raspberry Pi 3, but I don't want to do video processing on it. All this I have, just need to put them together. Adding AGX Orin will be a big thing. That's actually the goal. With video processing and LLM all in one mobile robot. As it's hobby R/D it will be configured and reconfigured many times. That's why I don't want to do low level by hand every time.

Another interesting option is Raspberry Pico * N + Tiny PC. For control and thinking. They can be connected via wifi or blutooth.

sadhorse · 4 months ago

What kind of vision peocessing are you envisioning?

sadhorse commented on Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably kumarletter.com/posts/ele... · Posted by u/kumarski

epicureanideal · 5 months ago

People drive to work anyway. A vacation or two every year is probably not even a double digit percent of a person’s total fossil fuel usage, and gives them a lot of happiness and reason to work and do things that are good for society.

Also: https://en.m.wikipedia.org/wiki/Fuel_economy_in_aircraft

sadhorse · 5 months ago

It is pollution and it harms people. So in order to do things that are good we must harm others first (or after)?

sadhorse commented on Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably kumarletter.com/posts/ele... · Posted by u/kumarski

lucidguppy · 5 months ago

Flight is a luxury of the current times that will likely not last another 100 years except for the very rich.

sadhorse · 5 months ago

How dare you stand in the way of regular people burning hundreds of kilograms of fossil fuel in order to spend a couple days at the beach? /s

sadhorse commented on The race is on to build the most complex machine economist.com/science-and... · Posted by u/_tk_

carabiner · 6 months ago

Could this fail in some way and cause a resonance cascade?

sadhorse · 6 months ago

Not if we follow strict operating procedures, Gordon.

sadhorse commented on How can this 6 axis robot have a static accuracy of 0.05 mm? (2021) [video] youtube.com/watch?v=SioCw... · Posted by u/unclefuzzy

amelius · 10 months ago

Doesn't this youtube project infringe on the patent which this company holds, then?

https://electroimpact.com/Company/PatentFiles/US8989898B2.pd...

sadhorse · 10 months ago

Legit question: if I replicate a patent for a personal non profit use, is this infringement? Perhaps it is because I'm benefiting from the intelectual property.

sadhorse commented on How can this 6 axis robot have a static accuracy of 0.05 mm? (2021) [video] youtube.com/watch?v=SioCw... · Posted by u/unclefuzzy

maille · 10 months ago

I'm curious what would be the best way to replicate an x/y (optionally z) system with 0.05mm or lower accuracy? Without sacrificing speed of course.

sadhorse · 10 months ago

Depends on how much power you need (speed times force, acceleration and deceleration...) and how much stiffness you need (can't bend?).

Also depends on how much travel you need. It is easier to get 50 micron accuracy over a total length of 100 micron compared to a total length of 1 meter.

sadhorse commented on Emergence of ferromagnetism at onset Kondo breakdown in moiré bilayer lattices phys.org/news/2024-10-phy... · Posted by u/wglb

wbl · 10 months ago

Temperature measures entropy as a systems energy changes. This is a system where the high energy state is less entropic.

sadhorse · 10 months ago

Is this related to lasers behaving as as a body with negative temperature when they manage to heat something to a hotter temperature by radiation?

sadhorse commented on Microwaves: A Haven for Bacterial Diversity tecscience.tec.mx/en/biot... · Posted by u/rbanffy

galdosdi · a year ago

Because microwaves don't heat matter. They heat* H2O molecules. This one weird fact is responsible for all of the weird differences between how they cook and how other more classic cooking methods work.

We're taught that heating has three styles: convection, conduction, radiation. But AFAIK, microwaving is a fourth and distinct style.

*: Even more specifically, they add rotational momentum to these molecules, which is not the same as heat, but gradually turns into heat (which is translational momentum) as they knock around. This, in addition to the fact that only the water is being heated, and that the microwave waves touch the food in an uneven pattern even if mitigated by a rotating platter, is why stirring or waiting or using "low power" (dithered) is an important part of microwave recipes, as well as why high moisture foods or intentional steaming works so much better in it

sadhorse · a year ago

Microwave heating is not a fourth form of heat transfer as it name implies: microwave radiation. Yes, the heat is not being radiated by a thermal source of microwaves, but it is radiation being absorbed. Hence radiation is the mechanism.

Rotational momentum is also heat as it is kinect energy related to movement, linear or not.

sadhorse commented on Secure Boot is broken on 200 models from 5 big device makers arstechnica.com/security/... · Posted by u/verifex

rebolek · a year ago

It's a bit of surprise that most of the things work most of the time, given on how shaky basis are they build.

sadhorse · a year ago

If you dig deep enough all our land is on a floating basis.