Relays can be used for anything, and a car contains a fair number.
You can make a pulse jet engine from a muffler parts, but a solarpunk society would probably not do that. :)
Copper brake pipe and cooling radiators can be used as heat exchangers for other stuff.
Air conditioner parts can be reverse-used for Stirling engines or to pump heat in other contexts.
Wow, really interesting tools. :)
But sadly not for me - I left biology behind at some point and have fallen off the sleigh so badly that I’d probably need a year of study before I could use this tool for something less than practical (e.g. make a bacterium glow in the dark).
Apparently, the Caspian Sea Monster is back, and it’s electric now. :) If I had a need for watercraft (I live on land and I don’t need more than a SUP board), this would be something that I’d try building (naturally with seatbelts and airbags to survive a crash). :)
Tesla’s favourability with car repair technicians probably never exceeded 5%. :)
It’s a maintenance nightmare and a far cry from even slight futureproofness. If someone dumps it on you for 1000 euros with a working battery, take the battery apart and sell the rest for 500 euros. ;P
(sums slightly underestimated) ;)
Nice to have it here, but due to the practical nature of the demonstration, I think this video could have flown better on c/technology or c/diy - or something of that sort. :)
But yep, moving heat is a lot smarter than creating it. :)
But that’s not what we found. In fact, experimental manipulations that reduced support for the protesters had no impact on support for the demands of those protesters.
We’ve replicated this finding across a range of different types of nonviolent protest, including protests about racial justice, abortion rights and climate change, and across British, American and Polish participants (this work is being prepared for publication). When members of the public say, “I agree with your cause, I just don’t like your methods,” we should take them at their word.
Wow, that is both new (at least for me) and interesting - thanks for sharing this article. :)
I note a potential weakness in the method of analysis: if negative framing (e.g. by the media) reduces support for the protesters as persons (but not their cause), it may still somewhat harm their ability to bring about change, since it probably reduces people’s willingness to team up with them - but not another group which has the same cause but different methods.
So, if the goal is mass action (which has a component of mobilizing like-minded people to join) I would strongly recommend a protester to choose non-controversial methods (so that even grannies can join). :)
I would add:
If the motor mount is hackable with reasonable effort, and the motor controller’s interfaces are open, then in principle… yes.
Yet in reality, companies build extremely complicated cars where premature failure of multiple components can successfully sabotage the whole. :(
I’ve once needed to repair a Mitsubishi EV motor controller. It took 2 days to dismantle. Schematics were far beyond my skill of reading electronics, and I build model planes as an everyday hobby, so I’ve seen electronics. Replacement of the high voltage comparator was impossible as nobody was selling it separately. The repair shop wanted to replace the entire motor controller (5000 €). Some guy from Sweden had figured out a fix: a 50 cent resistor. But installing it and putting things back was not fun at all. It wasn’t designed to be repaired.
Needless to say, replacing a headlight bulb on the same car requires removing the front plastic cover, starting from the wheel wells, undoing six bolts, taking out the front lantern, and then you can replace the bulb. I curse them. :P
But it drives. Hopefully long enough so I can get my own car built from scratch.
Thanks for the news, but also - thanks for posting a proper summary. :)
(So many videos have only the YouTube-compiled summary, which is typically totally off topic.)
Nice to hear. :) The process seems doable in a suitably equipped factory. :)
The transfer to electricity could be done by using the heated mass to heat a hot pumped liquid or using transfer rods made of a solid material with a high heat transfer coefficient.
Alternatively, heat can be extracted by pumping liquid metal (sodium, tin, low-temperature eutectic alloys) in a pipework of copper (if there is chemical compatibility with copper). But handling liquid metal with a magnetic pump isn’t typically done on the DIY tech level.
To be honest, I tried a fair number of experiments on the subject, including low-temperature Stirling motors. They’re difficult to build well. I would recommend plain old steam turbine. Steam means pressure, pressure means precautions (risk of bursting, risk of getting burned), but modern approaches to boilers try to minimize the amount of water in the system, so it couldn’t flash to steam and explode.
I have superficially researched both options (with the conclusion that I cannot use either, since my installation would be too small, and would suffer from severe heat loss due to an unfavourable volume-to-surface ratio - it makes sense to design thermal stores for a city or neighbourhood, not a household).
I’d add a few notes:
A thermal store using silicate sand is not limited by the melting point of the sand, but the structural strength of the materials holding the sand. You can count on stainless steel up to approximately 600 C, more if you design with reserve strength and good understanding of thermal expansion/contraction. Definitely don’t count on anything above 1000 C or forget the word “cheap”. I have read about some folks designing a super-hot thermal store, but they plan to heat graphite (self-supporting solid material) in an inert gas environment.
Heat loss intensifies with higher temperatures, and the primary type of heat loss becomes radiative loss. Basically, stuff starts glowing. For example, the thermal conductivity of stone wool can be 0.04 W / mK at 10 C, and 0.18 W / mK at 600 C.
Water can be kept liquid beyond 100 C. The most recent thermal stores in Finland are about 100 meters below surface, where the pressure of the liquid column allows heating water to 140 C.
However, any plan of co-generation (making some electricity while extracting the stored heat) requires solid materials and high temperatures.
Thanks, that looks like something I might have to try. :) Myself, over the network, I still don’t do filesystem level incremental backups, sticking to either directories or virtual machine snapshots (both of which have their shortcomings).
I’ve been hearing about ZFS and its beneficial features for years now, but mainstream Linux installers don’t seem to support it, and I can’t be bothered to switch filesystems after installing.
Out of curiosity - can anyone tell, what might be blocking them?
Edit: answering my own question: legal issues. Licenses “potentially aren’t compatible”.
Due to potential legal incompatibilities between the CDDL and GPL, despite both being OSI-approved free software licenses which comply with DFSG, ZFS development is not supported by the Linux kernel. ZoL is a project funded by the Lawrence Livermore National Laboratory to develop a native Linux kernel module for its massive storage requirements and super computers.
Source: https://wiki.debian.org/ZFS
Being informed that “from now on, we’ll use Microsoft development tools” because our branch in $other_country decided to.
Soon after that, I informed the boss that I’d wrap my projects up (using development tools of my choosing) during the subsequent year, and then leave, and support the projects in future as a subcontractor.
So I went and started my one-person-company. It was hard, but so far it has worked.
From a person who builds robots, three notes:
Raspberry Pi has two CSI (camera serial interface) connectors on board, which is a considerable advantage over having to deal with USB webcams. This matters if your industrial robot must see the work area faster, your competition robot must run circles around opposing robots, or more sadly - if your drone must fly to war. :( On Raspberry Pi, in laboratory conditions (extreme lighting intensity), you can use the camera (with big ifs and buts) at 500+ frames per second, not fast enough to photograph a bullet, but fast enough to see a mouse trap gradually closing. That’s impossible over USB and unheard of to most USB camera makers.
I know that Raspberry Pi has “WiringPi” (a fast C library for low level comms, helping abstract away difficult problems like hardware timing, DMA and interrupts) and Orange Pi recently got “WiringOP” (I haven’t tried it, don’t know if it works well). I don’t know of anything similar on a PC platform, so I believe that on NUC, you’d have to roll your own (a massive pain) or be limited to kilohertz GPIO frequencies instead of megahertz (because you’d be wading through some fairly deep Linux API calls).
Sadly, neither of them has a WiFi antenna socket. But the built-in WiFi cards are generally crappy too, so if you needed a considerable working area, you’d connect an external card with an external antenna anyway. Notably, some models of Orange Pi have an external antenna, and the Raspberry Pi Compute Module has one too.
I played the idea a few years back, at some anarchist-leaning not-just-music festival. We tried setting up a link over a 70 m hill, both stations using 433 MHz (500 mW transmit power, quarter wave antennas) narrowband (no frequency hopping) LoRa boards from Chengdu EByte. Stick antennas, not directional. Both stations were right below the hillside, so the hill formed a perfect obstacle between them.
Communicating over the hill in a single hop proved impossible. With a repeater at the hilltop, it was possible to make contact with the repeater from street level (no line of sight, trees obstructing), but the repeater (Meshtastic didn’t exist back then, it was entirely homebrew) had software bugs, so - no link to the other hillside. :)
With better software and better planning, the experiment would have succeeded. :) And if we’d have tried building a link over a valley, it would have been considerably easier.
With ordinary WiFi and directional antennas (panel or ladder antennas), I’ve been able to establish links over 1 km. If one used a LoRa card, and had a directional antenna for the frequency involved, in clear line of sight, I believe 10 km would be attainable without being a radio specialist.
It looks beautiful, but a bit fragile - I’m not used to seeing wooden wings and a jet turbine. :)
I would feel more confident with a propeller-electric rebuild of Antonov An-2 “crop duster”. Which sadly doesn’t exist. :( Someone has to do it, or do a similar thing. :)
Thanks for the advance warning, I hope it goes well. :)
Relays: my use for truck relays is switching on heaters in my thermal storage water tank. Not big ones, though - I use relays rated for 24V and 40A of current. Since they are old, I have applied a safety margin and only let 25 A flow through them, so each of them handles 24 x 25 = 600 W.
As for using DC appliances: benefits do exist. If a household has a low voltage DC battery bank (some do, some don’t) then dropping the battery voltage a few times to power car parts comes with a smaller efficiency loss. In my household, DC appliances are used for lighting, communications, computing, cooling food, pumping water and soldering electronics. The rest goes via AC. I think a car air conditioner could cool some small storage room decently. With big living rooms, it would have difficulty since it’s a small device.