At Maker Faire Milwaukee this past weekend, [basement tech] was showing off his latest build, a PID controlled charcoal grill. While it hasn’t QUITE been tested yet with real food, it does work in theory.
PID (a feedback loop with some fancy math used to adjust the input to get a consistent output) controlled cooking is commonly used for sous vide, where one heats up a water bath to a controlled temperature to cook food in plastic bags. Maintaining water temperature is fairly easy. Controlling a charcoal barbecue is much more difficult. [basement tech] accomplishes this with controlled venting and fans. With the charcoal hot and the lid on, there are two ways to control temperature; venting to let hot air out, and blowing air on the coals to make them hotter. A thermocouple sensor stuck through the grill gives the reading of the air inside, and an Arduino nearby reads that and adjusts the vents and fans accordingly.
The video goes into extensive detail on the project, and describes some of the challenges he had along the way, such as preventing the electronics and servos from melting.
Continue reading “PID Controlled Charcoal BBQ – Put an Arduino on it!”
There is something special about food that has been cooked in a grill, barbecue, or broiler. The charred surface brings both flavour and texture to the food, that other cooking methods fail to emulate. Of course, should you come from a part of the world in which the locals steam their hamburgers those are fighting words, but for [Robots Everywhere] the prospect of a flaccid patty cooked in a microwave oven was too much.
His solution? Broil the microwaved meat in double-quick time, using a plasma arc generated with a high voltage supply. The patty is placed in a grounded metal frying pan, and the high voltage probe is run over each side with accompanying plasma and sparks to lend that essential grilled exterior.
The power supply is a fairly simple affair, if a little hair-raising. A simple push-pull MOSFET oscillator drives a pair of flyback transformers whose secondaries are connected in series. It’s not the most efficient way to generate high voltages with a flyback transformer – the key is in the word “flyback” – but it generates enough juice for the job in hand.
It’s hardly the safest cooking method, and we’d be worried about contamination from whatever metal the electrode is made from. But it’s entertaining to watch, as you’ll be able to see from the video below the break.
Continue reading “Cooking With The Awesome Power Of Plasma!”
If your idea of a six-course meal is a small order of chicken nuggets, you might have missed the rise of sous vide among cooks. The idea is you seal food in a plastic pouch and then cook it in a water bath that is held at a precise temperature. That temperature is much lower than you usually use, so the cook times are long, but the result is food that is evenly cooked and does not lose much moisture during the cooking process. Of course, controlling a temperature is a perfect job for a microcontroller and [Kasperkors] has made his own setup using an Arduino for control. The post is in Danish, but Google translate is frighteningly good.
The attractive setup uses an Arduino Mega, a display, a waterproof temperature probe, and some odds and ends. The translation does fall down a little on the parts list, but if you substitute “ground” for “earth” and “soil” you should be safe. For the true epicurean, form is as important as function, and [Kasperkors’] acrylic box with LEDs within is certainly eye-catching. You can see a video of the device, below.
Continue reading “Sous Vide Arduino isn’t Lost in Translation”
Looking at the plate on the bottom of his electric rice cooker, [AC_Hacker] was surprised to find that it was rated to consume 400 watts. Furthermore when he measured its consumption he found that it consumed 385 watts without even having a cooking cycle initiated. The circuit to keep cooked rice warm was always on – even when the cooking circuit wasn’t engaged.
Something clearly had to be done, so he set about modifying the cooker for better economy. Removing the base revealed that disabling the warming circuit was as simple as disconnecting it. [AC_Hacker] also noticed that the device had no thermal insulation. There was plenty of space between the inner and outer walls, so he packed it with glass wool. The final modification was to reduce the power taken by the heater by installing a half-wave rectifier diode. The cooker still reached the desired temperature, it just used half the power.
You might think that would be the end of it, given that the modifications significantly reduced the cooker’s power consumption without detriment to its rice cooking ability. Rice now took a little longer to cook, so there was still room for improvement. The moment of inspiration came when [AC_Hacker] realized that the cooking time was proportional to the amount of water used in a cooking cycle. He could safely reduce the water without affecting the cooked rice. A 30% water reduction led to a proportional cooking time reduction, and rice cooked using a lot less power.
Surprisingly this seems to have been Hackaday’s first rice cooker hack. Perhaps that’s because you’ve been so busy supplying us with sous vide hacks to write about.
Sometimes along comes a machine so simple yet so alluring in what it does and how it achieves its aim that you just want one. Doesn’t matter what it does or indeed whether ownership is a practical proposition, you wish you could have one in your possession.
What machine could trigger this reaction, you ask? [Robbie Van Der Walt] and [Christiaan Harmse] have the answer, their machine performs the simple but important task of cooking an endless pancake. A hopper dispenses a layer of pancake batter onto a slowly rotating heated roller that cooks the ribbon of pancake on one side, before it is transferred to another roller that cooks the other side. It seems simple enough yet the simplicity must hide a huge amount of product refinement and probably many miles of lost pancake. Pancakes it seems are a traditional South African delicacy, evidently they must have king-sized appetites to satisfy.
In the video below (Afrikaans, English subtitles) they make an attempt at a world record for the longest ever pancake, though sadly they don’t seem to appear in a Guinness World Records search so perhaps they didn’t achieve it. Still, their machine is a work of art, and we applaud it. Continue reading “Endless Pancakes”
In case you didn’t know it, pancake art is a thing. People are turning out incredible edible artwork using squeeze bottles and pancake batter. But even if you’re not terribly artistic, you can still amaze your breakfast buddies with this robotic pancake printer.
At its simplest – and in our opinion its most impressive – pancake art involves making patterns with thin batter on a hot griddle. The longer the batter is cooked, the darker it becomes, and art happens. To capitalize on this, [Trent], [Kevin], [Sunny] and [Isaac] built a 2-axis gantry with a working area the size of an electric griddle. A bottle is pressurized with a small air pump and controlled by a solenoid valve to serve as a batter extruder, and an Arduino controls everything. Custom pancake design software lets you plan your next masterpiece before committing it to batter.
Sadly, the video below shows us that the team didn’t include an automatic flipper for the pancake, but no matter – that’ll make a great feature for the next version. Maybe something like this?
Continue reading “Edible art from a Robot Pancake Printer”
The summer may have come to a close here in the USA, but any time of the year is a good time for grilling. In the colder weather, it’s a drag to have to stay near the hot grill to keep an eye on your burgers and franks. [Eric Ely] thought it would be smarter to have a meat thermometer that sent his phone the current reading via Bluetooth.
Instead of starting from scratch, [Eric] took an off the shelf electronic thermometer and removed its temperature probe (which was a thermistor). The hardware used an off the shelf Bluetooth board with a companion battery board and prototype board. If you can’t bear to cut up a good thermometer, you can get replacement probes that ought to work just as well.
In addition to the boards and the scavenged thermistor, [Eric] used a couple of resistors. One resistor is in parallel with the thermistor to improve the linearity of the device’s response curve. The second resistor forms a voltage divider that the Bluetooth board reads.
The software (using Node.js and C) is available on Github. The C program reads the temperature and pushes it out using JSON. Node.js provides a server that [Eric] can hit with his phone’s Web browser.
Sure, you can buy wireless thermometers, but what self-respecting hacker wants to carry around a store-bought box just to display meat temperature? Viewing it on your phone has much more street cred. Of course, a real hacker isn’t going to cook on a conventional grill, either.
Continue reading “Bluetooth Thermometer Minds Your Meats”