A Linux-powered microwave oven
A Linux-powered microwave oven
Posted Feb 12, 2016 0:14 UTC (Fri) by pr1268 (guest, #24648)In reply to: A Linux-powered microwave oven by fratti
Parent article: A Linux-powered microwave oven
I'm sure everybody in here has one or more home appliances where 90% of the buttons go unused because it's just not worth the hassle to look up what they do, mostly because the basic functionality already does the job well enough.
A resounding "Amen!" to that.
A microwave oven is merely a Faraday cage with a magnetron, a lamp, a swing-out latching front door, and an on/off switch for the magnetron (since it only has two working states: full-power and off).
I find it oddly eccentric that the appliance companies have seemed bent for the past several decades on adding all these fancy bells & whistles to microwave ovens to fine-tune the heating parameters. Note that I said "heating" and not "cooking"—you really can't cook with a microwave oven. And, considering how dielectric heating works, you can't effectively heat anything which does not contain water.
I sincerely do not mean to impugn Mr. Tulloh's hard work nor Neil's excellent article. In fact, I'm quite impressed with some of the ingenuity shown by this project. But, there's something to be said about the KISS method—especially when you're working with a device that has only two discrete states of operation.
</minor rant>
P.S. I have fond memories of using my grandmother's microwave oven (vintage early 1980's). It had only two controls: (1) an egg timer-style power knob, and (2) a large mechanical latch button to open the door. Worked great for years.
Posted Feb 12, 2016 14:55 UTC (Fri)
by robbe (guest, #16131)
[Link] (1 responses)
David’s additions, though, seem to provide more value than the usual ones (a clock that’s always wrong, silly menus, …). I especially like the infrared sensor. I am less excited about the lack of a turntable. But maybe this spinner part can replace it reliably?
Posted Feb 19, 2016 18:37 UTC (Fri)
by Wol (subscriber, #4433)
[Link]
And both hers and mine have various features I would NOT want to lose. Namely heating elements at the top (commonly known as "a grill"), and at the back (commonly known as a "fan oven").
Our kitchen now has a conventional oven and a combi-oven built-in, and the combination is great. Incidentally, for those who think AU$1K is expensive, if I could get a built-in combi for that price I would consider it very good value for money.
The one big problem with our new - analog - combi is we have to remember to check the settings each time we use it. My old - digital - oven reset itself back to its defaults after every use. It also had the ability to set several programs to run consecutively - made superb baked tatties - set it for 10 mins on combi followed by 10 mins on fan oven and one lovely tatty. Our new analog you have to do the first setting, then when it bleeps "finished" you need to go back and reset it for the second setting.
Cheers,
Posted Feb 12, 2016 15:21 UTC (Fri)
by fratti (guest, #105722)
[Link] (9 responses)
I have this creeping suspicion that's it's an attempt to differentiate themselves from the competition without actually having to innovate. A lot of home appliances have come to a state where it would take some serious engineering to make a substantial improvement over previous models (which is expensive), so to keep up a fake air of technological evolution (as we've come to expect it from other devices such as computers or phones), they just tack things on that makes them look more advanced than it really is.
One anecdote I have of kitchen appliances that have essentially reached an innovation plateau is when my family's old hand mixer broke. We've had it for probably over a decade, maybe even more. When my mother came back from the store, she did so with the exact same model. Same white plastic mould that would slowly become yellow over the years with a teal push button on the top to release the attachments and one switch that had several positions to adjust speed, powered with a somewhat flimsy two-wire power cord. Not only did they still produce and sell it, the salesman even recommended it to her, because essentially there have been no improvements over the years. Yes, maybe internally the power supply or the motor were using newer parts, but it's still just an electric motor that you can plug into a wall outlet to spin mixing or puréeing attachments of various shapes.
Posted Feb 12, 2016 17:02 UTC (Fri)
by raven667 (subscriber, #5198)
[Link] (7 responses)
OMFG yes, I actually find that for many appliances, they really peaked in the 1950s and the actual utility has been on a plateau or decline since then. Maybe I am just getting old and cranky but I'm not excited about tools like the Nest thermostat or fancy Microwave because the more software the harder it is to reason about what the device is going to do, it becomes a mysterious black box with rules that you just can't quite spend the mental effort to figure out, because we all have better things to do with our time. Instead of our appliances being tools we use we become tools for babysitting the appliances, and a machine for vomiting up cash to the manufacturer.
There is also a lot of advertising out there to convince people that every chore is just _too_hard_ and you need a much larger number of appliances than are really necessary. Take a look at one of the many cooking competition shows to see how many appliances are actually useful in a kitchen.
Posted Feb 12, 2016 19:14 UTC (Fri)
by rgmoore (✭ supporter ✭, #75)
[Link]
I'm not sure I'd go that far, but I agree that development is very slow, especially compared to anything involving computers. The key is that for anything, the biggest change is from having nothing to having something, and after that it's mostly refinement, and often with declining returns. An icebox is a huge improvement over nothing, a refrigerator is a big advance over an icebox, but after that you're chasing improvements in convenience and efficiency rather than basic function. Similarly, many of the changes to the microwave (e.g. turntable for the food, variable power level) are real improvements, but they're marginal advances compared to getting one in the first place.
Posted Feb 12, 2016 19:17 UTC (Fri)
by bronson (subscriber, #4806)
[Link] (3 responses)
Now that's progress!
Posted Feb 18, 2016 12:54 UTC (Thu)
by nye (subscriber, #51576)
[Link] (2 responses)
Posted Feb 18, 2016 14:29 UTC (Thu)
by spaetz (guest, #32870)
[Link] (1 responses)
Easy, so it can order champagne when you have planned your next orgy. SCNR
Posted Feb 19, 2016 0:23 UTC (Fri)
by dfsmith (guest, #20302)
[Link]
Posted Feb 13, 2016 23:35 UTC (Sat)
by mathstuf (subscriber, #69389)
[Link] (1 responses)
Those "As Seen on TV" bits should be viewed in light of being targeted at those with disabilities or handicaps. The reason they show normal people purposefully failing is because someone with Parkinson's failing to cleanly break an egg is not something anyone wants to tape, be taped doing, or watch.
Posted Feb 14, 2016 2:51 UTC (Sun)
by raven667 (subscriber, #5198)
[Link]
Posted Feb 12, 2016 19:02 UTC (Fri)
by rgmoore (✭ supporter ✭, #75)
[Link]
Pretty much. Most of them are relatively simple mechanical tools for performing mechanical tasks- chopping, mixing, blending, etc.- so that there isn't a huge amount to change. They seem to do a few basic things- changing cosmetics, expanding the product line to larger or smaller models, making the motor more powerful, or just trying to squeeze out production costs- that don't change the basic functions. There is some genuine innovation out there- I've been amazingly happy with my induction range, which is a huge advance over conventional electric stoves- but it happens much slower than in tech.
Posted Feb 13, 2016 5:13 UTC (Sat)
by luto (guest, #39314)
[Link] (4 responses)
Not quite. The Panasonic "inverter" ovens (and their licensees) do a credible job of running at partial power.
Posted Feb 13, 2016 7:45 UTC (Sat)
by pr1268 (guest, #24648)
[Link] (2 responses)
Interesting... I was thinking of inventing a microwave oven with two independently-controlled magnetrons, each with a different thermal power rating (e.g. 400W and 700W). Any combination of running either/both could give three different heating states (approx. 1/3, 2/3, and full power). Running one continuously and the other toggling on/off (partial load) could give even more discrete power levels. Of course, there's the unwritten postulate that the complexity of mechanical devices with n parts is O(n1.5). Or thereabouts. Adding another magnetron would make the microwave oven unnecessarily more complicated. Oh, well...
Posted Feb 17, 2016 23:58 UTC (Wed)
by opalmirror (subscriber, #23465)
[Link] (1 responses)
Posted Feb 20, 2016 22:46 UTC (Sat)
by pr1268 (guest, #24648)
[Link]
Dammit, Jim, I'm a computer scientist, not an electrical engineer with a background in microwave propagation effects! ;-) Of course, my "invention" was just a thought-concept; the scenario you just described succinctly (and graphically) describes why such a microwave oven has not been introduced. Like I said, for n extra parts, O(n1.5) complexity... A sincere thank you for enlightening me. :-)
Posted Feb 16, 2016 16:18 UTC (Tue)
by sdalley (subscriber, #18550)
[Link]
Went back to a more straightforward on-off microwave, which is is still going fine after 3 years.
KISS, indeed.
A Linux-powered microwave oven
A Linux-powered microwave oven
Wol
A Linux-powered microwave oven
A Linux-powered microwave oven
A Linux-powered microwave oven
I actually find that for many appliances, they really peaked in the 1950s and the actual utility has been on a plateau or decline since then.
A Linux-powered microwave oven
A Linux-powered microwave oven
A Linux-powered microwave oven
A Linux-powered microwave oven
A Linux-powered microwave oven
A Linux-powered microwave oven
A Linux-powered microwave oven
A lot of home appliances have come to a state where it would take some serious engineering to make a substantial improvement over previous models (which is expensive), so to keep up a fake air of technological evolution (as we've come to expect it from other devices such as computers or phones), they just tack things on that makes them look more advanced than it really is.
A Linux-powered microwave oven
Partial-power microwave oven
Not quite. The Panasonic "inverter" ovens (and their licensees) do a credible job of running at partial power.
So here you have two magnetrons relatively tightly coupled, resonant at approximately the same frequency, one powered and one unpowered. To me it seems the unpowered magnetron acts as an ideal resonant antenna to receive RF power from the powered magnetron. Even if the unpowered magnetron is connected to an open circuit, I'd expect significant currents and waste heat generation.
If both magnetrons are powered and coherent (same frequency), then synchronization of their output might be tricky - they would have to be in the same phase, or they would be exchanging a lot of power one to the other. The fact one is twice the power of the second could mean the large magnetron may burn up the smaller magnetron or send current back into its power supply.
Maybe you could detune them (different frequencies) and/or use a cavity resonator as a narrow pass filter so that one magnetron isn't very much affected by the other. Cavity resonators would add mass and size and no doubt reduce efficiency by producing still more heat.
Just thinking...
Partial-power microwave oven
Partial-power microwave oven
Cavity resonators would add mass and size and no doubt reduce efficiency by producing still more heat.
A Linux-powered microwave oven