Kids Kitchen That Says BEEP

Children have always liked to learn by copying the adults around them, and thus have always desired toys that emulate the tools which their older forebears use on a daily basis. [rhoalt]’s daughter wished for an oven to play with, so a trip to IKEA was in order to get started.

The build begins with the IKEA Duktig, a beautiful fun-sized oven. [rhoalt] then breaks out the hacker staple foods of 7-segment displays, swanky backlit buttons and an Arduino Nano. Through some careful handiwork, the wooden panels that make up the toy oven are drilled and routed out to fit the components.

The electronics are all used to create an oven with a digital timer, and the final effect achieved is rather nice. The glowy buttons can be used to set and reset the timer, while an LED strip inside lights up to simulate cooking. [rhoalt] shares all the construction details along with some parent-friendly tips, like taping over the buzzer to reduce the volume, and ensuring the timer is limited to 10 minutes to avoid any late-night surprises.

It’s a tidy project with a strong sense of fun, and the presentation is top-notch. Even we older, jaded hackers light up for a good glowy-buttoned project, so we’re sure [rhoalt]’s daughter loves her new toy. For more toy oven action, check out this Easy Bake converted to USB. Video after the break.

Continue reading “Kids Kitchen That Says BEEP”

Cell Phone Surveillance Car

There are many viable options for home security systems, but where is the fun in watching a static camera feed from inside your place? The freedom to really look around might have been what compelled [Varun Kumar] to build a security car robot to drive around his place and make sure all is in order.

Aimed at cost-effectiveness and WiFi or internet accessibility, an Android smartphone provides the foundation of this build — skipping the need for a separate Bluetooth or WiFi module — and backed up by an Arduino Uno, an L298 motor controller, and two geared DC motors powering the wheels.

Further taking advantage of the phone’s functionality, the robot is controlled by DTMF tones. Using the app DTMF Tone Generator and outputting through the 3.5mm jack, commands are interpreted by a MT8870DE DTMF decoder module.While this control method carries some risks — as with many IoT-like devices — [Kumar] has circumvented one of DTMF’s vulnerabilities by adding a PIN before the security car will accept any commands.

He obtains a live video feed from the phone using AirDroid in concert with VNC server, and assisted by a servo motor for the phone is enabled to sweep left and right for a better look. A VNC client on [Kumar]’s laptop is able to access the video feed and issue commands. Check it out in action after the break!

Continue reading “Cell Phone Surveillance Car”

Smell That? It’s time.

Steampunk is beautiful. There is something about the exposed metal and primitive looking artifacts that visually appeal to the brain of a maker and engineer alike. Makers have been busy the last decade building clocks with this theme because hey, everyone needs a clock. [Fuselage] has put together a Steam Punk Clock that releases actual steam(actually steam oil smoke) for its hourly chime. How cool is that?

The clock is designed around the Conrad C-Control Unit (translated) which has the Motorola 68HC08 and [Fuselage] uses BASIC to write the routines for the system. Unlike a lot of steampunk clocks that use Nixie Tubes, this one uses 4 Numitron displays for the hours and minutes display. An analog dial panel display is employed for the seconds’ and is driven by a PWM signal. The absence of the RTC module was not obvious until we saw that the BOM includes a DCF77 receiver. For the uninitiated, DCF77 is a longwave time signal and standard-frequency radio station in Mainflingen, Germany. If you are anywhere within a 2000 km range of that location, you can pick up a 24-hr time signal for free which is excellent if you plan to make say… a radio clock.

The steam/smoke generator is a subproject of sorts. The custom machine is designed to have a separate oil reservoir and pump in addition to the actual generator so that the system does not run out of fuel as quickly. Clearly [Fuselage] did his homework which is explained in brief in his project logs. The final design has a brass tube as the main heating and also serves as the outlet chamber. The oil is pumped from under the heating filament in the brass tube, and excess fluid drains off back into the reservoir. A piece of nichrome wire serves as the filament that vaporizes the liquid to gaseous form. Sensors make sure of the oil levels in the reservoir as well as the steam tube. Servo motors and fans add the effect of the opening the exhaust rain cap, and a small LED helps illuminate the exhaust to complete the impression of real steam.

The project is a great example of a simple but effective implementation and for those who are wondering about Numitron Tubes, check out this tutorial on the subject. Of course, there is the Giant Electro-mechanical Clock for those looking at more sizable works of art.

Continue reading “Smell That? It’s time.”

Repairs You Can Print: Broken Glue Gun Triggers Replacement

Picture this: you need to buy a simple tool like a glue gun. There’s usually not a whole lot going on in that particular piece of technology, so you base your decision on the power rating and whether it looks like it will last. And it does last, at least for a few years—just long enough to grow attached to it and get upset when it breaks. Sound familiar?

[pixelk] bought a glue gun a few years ago for its power rating and its claims of strength. Lo and behold, the trigger mechanism has proven to be weak around the screws. The part that pushes the glue stick into the hot end snapped in two.

It didn’t take much to create a replacement. [pixelk] got most of the measurements with calipers and then got to work in OpenSCAD. After printing a few iterations, it fit well enough, but [pixelk] saw a chance to improve on the original design and added a few teeth where the part touches the glue stick. The new part has been going strong for three months.

We think this entry into our Repairs You Can Print contest is a perfect example of the everyday utility of 3D printers. Small reproducible plastic parts are all around us, just waiting to fail. The ability to not only replace them but to improve on them is one of the brightest sides of our increasingly disposable culture.

Still haven’t found a glue gun you can stick to? Try building your own.

Making the Case for Open Source Medical Devices

Engineering for medical, automotive, and aerospace is highly regulated. It’s not difficult to see why: lives are often at stake when devices in these fields fail. The cost of certifying and working within established regulations is not insignificant and this is likely the main reason we don’t see a lot of work on Open Hardware in these areas.

Ashwin K. Whitchurch wants to change this and see the introduction of simple but important Open Source medical devices for those who will benefit the most from them. His talk at the Hackaday Superconference explores the possible benefits of Open Medical devices and the challenges that need to be solved for success.

Continue reading “Making the Case for Open Source Medical Devices”

Jill Tarter: Searching for E.T.

What must it be like to devote your life to answering a single simple but monumental question: Are we alone? Astronomer Jill Tarter would know better than most what it’s like, and knows that the answer will remain firmly stuck on “Yes” until she and others in the Search for Extraterrestrial Intelligence project (SETI) prove it otherwise. But the path she chose to get there was an unconventional as it was difficult, and holds lessons in the power of keeping you head down and plowing ahead, no matter what.

Endless Hurdles

To get to the point where she could begin to answer the fundamental question of the uniqueness of life, Jill had to pass a gauntlet of obstacles that by now are familiar features of the biography of many women in science and engineering. Born in 1944, Jill Cornell grew up in that postwar period of hope and optimism in the USA where anything seemed possible as long as one stayed within established boundaries. Girls were expected to do girl things, and boys did boy things. Thus, Jill, an only child whose father did traditional boy things like hunting and fixing things with her, found it completely natural to sign up for shop class when she reached high school age. She was surprised and disappointed to be turned down and told to enroll in “Home Economics” class like the other girls.

Doing “boy things” with Dad. Source: SETI Institute

She eventually made it to shop class, but faced similar obstacles when she wanted to take physics and calculus classes. Her guidance counselor couldn’t figure why a girl would need to take such classes, but Jill persisted and excelled enough to get accepted to Cornell, the university founded by her distant relation, Ezra Cornell. Jill applied for a scholarship available to Cornell family members; she was turned down because it was intended for male relatives only.

Undeterred, Jill applied for and won a scholarship from Procter & Gamble for engineering, and entered the engineering program as the only woman in a class of 300. Jill used her unique position to her advantage; knowing that she couldn’t blend into the crowd like her male colleagues, she made sure her professors always knew who she was. Even still, Jill faced problems. Cornell was very protective of their students in those days, or at least the women; they were locked in their dorms at 10:00 each night. This stifled her ability to work on projects with the male students and caused teamwork problems later in her career.

No Skill is Obsolete

Despite these obstacles, Jill, by then married to physics student Bruce Tarter, finished her degree. But engineering had begun to bore her, so she changed fields to astrophysics for her post-graduate work and moved across the country to Berkeley. The early 70s were hugely inspirational times for anyone with an eye to the heavens, with the successes of the US space program and leaps in the technology available for studies the universe. In this environment, Jill figured she’d be a natural for the astronaut corps, but was denied due to her recent divorce.

Disappointed, Jill was about to start a research job at NASA when X-ray astronomer Stu Boyer asked her to join a ragtag team assembled to search for signs of intelligent life in the universe. Lacking a budget, Boyer had scrounged an obsolete PDP-8 from Berkeley and knew that Jill was the only person who still knew how to program the machine. Jill’s natural tendency to fix and build things began to pay dividends, and she would work on nothing but SETI for the rest of her career.

From the Bureaucratic Ashes

At Arecibo. Source: KQED Science

SETI efforts have been generally poorly funded over the years. Early projects were looked at derisively by some scientists as science fiction nonsense, and bureaucrats holding the purse strings rarely passed up an opportunity to score points with constituents by ridiculing efforts to talk to “little green men.” Jill was in the thick of the battles for funding, and SETI managed to survive. In 1984, Jill was one of the founding members of the SETI Institute, a private corporation created to continue SETI research for NASA as economically as possible.

The SETI Institute kept searching the skies for the next decade, developing bigger and better technology to analyze data from thousands of frequencies at a time from radio telescopes around the world. But in 1993, the bureaucrats finally landed the fatal blow and removed SETI funding from NASA’s budget, saving taxpayers a paltry $10 million. Jill and the other scientists kept going, and within a year, the SETI Institute had raised millions in private funds, mostly from Silicon Valley entrepreneurs, to continue their work.

Part of the Allen Telescope Array. Source: SETI Institute

The Institute’s Project Phoenix, of which Jill was Director until 1999, kept searching for signs of life out there until 2004, with no results. They proposed an ambitious project to improve the odds — an array of 350 radio telescopes dedicated to SETI work. Dubbed the Allen Telescope Array after its primary patron, Microsoft co-founder Paul Allen, the array has sadly never been completed. But the first 42 of the 6-meter dishes have been built, and the ATA continues to run SETI experiments every day.

Jill Tarter retired as Director of SETI Research for the Institute in 2012, but remains active in the SETI field. Her primary focus now is fundraising, leveraging not only her years of contacts in the SETI community but also some of the star power she earned when it became known that she was the inspiration for the Ellie Arroway character in Carl Sagan’s novel Contact, played by Jodie Foster in the subsequent Hollywood film.

Without a reasonable SETI program, the answer to “Are we alone?” will probably never be known. But if it is answered, it’ll be thanks in no small part to Jill Tarter and her stubborn refusal to stay within the bounds that were set for her.

Roll Your Own Magnetic Encoder Disks

[Erich] is the middle of building a new competition sumo bot for 2018. He’s trying to make this one as open and low-cost as humanly possible. So far it’s going pretty well, and the quest to make DIY parts has presented fodder for how-to posts along the way.

One of new bot’s features will be magnetic position encoders for the wheels. In the past, [Erich] has used the encoder disks that Pololu sells without issue. At 69¢ each, they don’t exactly break the bank, either. But shipping outside the US is prohibitively high, so he decided to try making his own disks with a 3D printer and the smallest neodymium magnets on Earth.

The pre-fab encoder disks don’t have individual magnets—they’re just a puck of magnetic slurry that gets its polarity on the assembly line. [Erich] reverse-engineered a disk and found the polarity using magnets (natch). Then got to work designing a replacement with cavities to hold six 1mm x 1mm x 1mm neodymium magnets and printed it out. After that, he just had to glue them in place, matching the polarity of the original disk. We love the ingenuity of this project, especially the pair of tweezers he printed to pick and place the magnets.

Rotary encoders are pretty common in robotics applications to detect and measure wheel movement. Don’t quite recall how they work? We’ll help you get those wheels turning.

via Dangerous Prototypes