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Archive for the ‘3d printed’ Category

You don’t have to be an extinct mammal or a Millennial to enjoy the smooth, buttery taste of an avocado. Being psychic on the other hand is definitely an advantage to catch that small, perfect window between raw and rotten of this divaesque fruit. But don’t worry, as modern problems require modern solutions, [Eden Bar-Tov], [Elan Goldberg], and [Mizpe Ramon] built the AvoRipe, a device to notify you when your next avocado has reached that window.

Taking both the firmness and color of an avocado as indicators of its ripeness into account, the team built a dome holding a TCS3200 color sensor as stand for the avocado itself, and 3D printed a servo-controlled gripper with a force sensor attached to it. Closing the gripper’s arms step by step and reading the force sensor’s value will determine the softness the avocado has reached. Using an ESP8266 as centerpiece, the AvoRipe is turned into a full-blown IoT device, reporting the sensor readings to a smartphone app, and collecting the avocado’s data history on an Adafruit.IO dashboard.

There is unfortunately one big drawback: to calibrate the sensors, a set of nicely, ripe avocados are required, turning the device into somewhat of a chicken and egg situation. Nevertheless, it’s a nice showcase of tying together different platforms available for widescale hobbyist projects. Sure, it doesn’t hurt to know how to do each part from scratch on your own, but on the other hand, why not use the shortcuts that are at our disposal to remove some obstacles — which sometimes might include programming itself.

If everything goes according to plan, Elon Musk says the first generation of SpaceX’s massive Starship will make an orbital flight before the end of 2020. That’s a pretty bold claim, but when you’ve made landing rockets on their tails as in the old science fiction pulp magazines seem routine, we suppose you’ve earned the right to a bit of bravado. We’re excited to see the vehicle evolve over the next several months, but even if the real one stays grounded, we’ll gladly take this “flying” Starship model from [Chris Chimienti] as a consolation prize.

A magnetic levitation module, we’re officially in the future.

Feeling a bit let down by the 3D printable models of the Starship he found online, [Chris] set out to build his own. But it wasn’t enough to just make his bigger, stronger, and more accurate to Starship’s current design; he also wanted to make it a bit more exciting. Some RGB LEDs an Arduino embedded in the “cloud” stand the rocket sits on was a good start, and the landing pad inspired by SpaceX’s real autonomous spaceport drone ship Just Read the Instructions looks great all lit up.

But this is Starship we’re talking about, a vehicle that could literally push humanity towards being a multi-planet species. To do it justice, you’ve really got to knock it out of the park. So [Chris] found a magnetic levitation module online that could support a few hundred grams, and set to work on making his plastic Starship actually hover over the landing pad.

As you might imagine, it was a bit tricky. The first versions of the rocket looked great but came out too heavy, so he switched over to printing the model in so-called “spiral vase mode” which made it entirely hollow. Now far lighter and with a magnetic plate fit into the bottom, it was stable enough to float on its own. For the final touch, [Chris] added some red LEDs and a coin cell battery to the base of the Starship so it looks like the sleek craft is performing a last-second landing burn with its “impossible” full-flow staged combustion engines.

This isn’t the first time we’ve seen a model rocket with an electronic glowing cloud under it, but it’s certainly the first one we’ve seen that could levitate in mid-air. While this little rocket might not make it all the way to Mars, we wouldn’t be surprised to see it touching down on the desks of other hackers and makers in the near future.

For Game of Thrones fans, it’s an awkward time. The show has ended its run on HBO (not without a certain level of controversy), the planned prequel is still years away, and who knows when George R. R. Martin will actually get around to writing the final books in the series. Fans have no choice but to entertain themselves while waiting for further tales of adventure from Westeros, which is how we get things like this motorized clock from [Techarge].

Inspired by the now iconic opening sequence from the HBO series, elements of the 3D printed model spin around while the theme song is played courtesy of a DFPlayer Mini MP3 player module and small 2 watt speaker. The audio hardware, motor, and four digit LED display module in the front are all connected to an Arduino with a custom PCB shield, giving the inside of the clock a very clean and professional appearance.

Around the back side [Techarge] has two small push buttons to set the hour and minutes, and a large toggle to control the music and movement. As of right now it needs to be switched on and off manually, but a future enhancement could see it kick on hourly.  We’d also like to see an RTC module added to the PCB, or better yet, switch over to the ESP8266 and just pull the time down from NTP.

Who knows? By the time you’ve built one of these clocks for yourself, and the hand-made Iron Throne phone charger stand to go with it, maybe ol’ George will have slipped out a new book. But don’t count on it.

Anansi in African folktale is a trickster and god of stories, usually taking physical form of a spider. Anansi’s adventures through oral tradition have adapted to the situation of people telling those stories, everything ranging from unseasonable weather to living a life in slavery. How might Anansi adapt to the twenty-first century? [odd_jayy] imagined the form of a cyborg spider, and created Asi the robot companion to perch on his shoulder. Anyone who desire their own are invited to visit Asi’s project page.

Asi was inspired by [Alex Glow]’s Archimedes, who also has a project page for anyone to build their own. According to [Alex] at Superconference 2018, she knew of several who have done so, some with their own individual customization. [odd_jayy] loved the idea of a robot companion perched on his shoulder but decided to draw from a different pool of cultural folklore for Asi. Accompanying him to various events like Sparklecon 2019, Asi is always a crowd pleaser wherever they go.

Like every project ever undertaken, there is no shortage of ideas for Asi’s future and [odd_jayy] listed some of them in an interview with [Alex]. (Video after the break.) Adding sound localization components will let Asi face whoever’s speaking nearby. Mechanical articulation for legs would allow more dynamic behaviors while perched, but if the motors are powerful enough, Asi can walk on a surface when not perched. It’s always great to see open source projects inspire even more projects, and watch them as they all evolve in skill and capability. If they all become independently mobile, we’ll need clarification when discussing the average velocity of an unladen folklore robot companion: African or European folklore?

Sometimes it’s necessary to make do with whatever parts one has on hand, but the results of squashing a square peg into a round hole are not always as elegant as [Juan Gg]’s programmable DC load with rotary encoder. [Juan] took a design for a programmable DC load and made it his own in quite a few different ways, including a slick 3D-printed enclosure and color faceplate.

The first thing to catch one’s eye might be that leftmost seven-segment digit. There is a simple reason it doesn’t match its neighbors: [Juan] had to use what he had available, and that meant a mismatched digit. Fortunately, 3D printing one’s own enclosure meant it could be gracefully worked into the design, instead of getting a Dremel or utility knife involved. The next is a bit less obvious: the display lacked a decimal point in the second digit position, so an LED tucked in underneath does the job. Finally, the knob on the right could reasonably be thought to be a rotary encoder, but it’s actually connected to a small DC motor. By biasing the motor with a small DC voltage applied to one lead and reading the resulting voltage from the other, the knob’s speed and direction can be detected, doing a serviceable job as rotary encoder substitute.

The project’s GitHub repository contains the Arduino code for [Juan]’s project, which has its roots in a design EEVblog detailed for an electronic load. For those of you who prefer your DIY rotary encoders to send discrete clicks and pulses instead of an analog voltage, a 3D printed wheel and two microswitches will do the job.

Digitizing an object usually means firing up a CAD program and keeping the calipers handy, or using a 3D scanner to create a point cloud representing an object’s surfaces. [Dzl] took an entirely different approach with his DIY manual 3D digitizer, a laser-cut and 3D printed assembly that uses rotary encoders to create a turntable with an articulated “probe arm” attached.

Each joint of the arm is also an encoder, and by reading the encoder values and applying a bit of trigonometry, the relative position of the arm’s tip can be known at all times. Manually moving the tip of the arm from point to point on an object therefore creates measurements of that object. [Dzl] successfully created a prototype to test the idea, and the project files are available on GitHub.

We remember the earlier version of this project and it’s great to see how it’s been updated with improvements like the addition of a turntable with an encoder. DIY 3D digitizing takes all kinds of approaches, and one example was this unit that used four Raspberry Pi Zeros and four cameras to generate high quality 3D scans.

Six-legged robots are nothing new, but if you’d like inspiration for your own, it would be hard to beat this 22 servo-driven, 3D-printed hexapod from Dejan at How To Mechatronics. 

The ant-inspired device features three metal geared servos per leg, as well as a pair to move the heat, another for the tail, and a micro servo to activate the mandibles.

To control this large number of servos, Dejan turned to the Arduino Mega, along with a custom Android app and Bluetooth link for the user interface. While most movements are activated by the user, it does have a single ultrasonic sensor buried in its head as “eyes.” This allows it to lean backwards when approached by an unknown object or hand, then strike with its mandibles if the aggressor continues its advance. 

As the name suggests, the hexapod has six legs but in addition to that, it also has a tail or abdomen, a head, antennas, mandibles and even functional eyes. All of this, makes the hexapod look like an ant, so therefore we can also call it an Arduino Ant Robot.

For controlling the robot I made a custom-built Android application. The app has four buttons through which we can command the robot to move forward or backwards, as well as turn left or right. Along with these main functions, the robot can also move its head and tail, as well as it can bite, grab and drop things and even attack.

You can see it in action and being assembled in the video below, and build files are available here.

What do you do when you need to attach 400-500 screws for an upcoming project? If you’re “Progress Thailand” you simply create one yourself using a 9g micro servo modded for continuous rotation, an Arduino Nano, and some 3D printing!

The build uses a small thumb joystick for proportional control, and can accommodate a small hand driver in addition to a bit by itself. Impressively, a functional prototype of the tool was produced in a single day, with the final(?) version appearing a couple of days later. 

Hand and power tools are cheap, reliable, and easily accessible. But their production is still done in large centralized factories. 3D printing technology and cheap, open source electronics continue to improve bringing the decentralization of manufacturing one step closer.

We are experimenting with different designs to see how close current 3D printing technology can bring us to production-quality tools you can buy in the store. We’re also experimenting to see what modifications we can make to store-bought tools to enhance and customize their use.

While they note that the project isn’t meant to replace commercial screwdrivers at this point, it looks like a fun project with all the needed files available here to modify and improve things to your specifications!

3D printers get most of the attention in maker-fabrication news, but other computerized tools, like laser cutters and CNC routers, can also be extremely useful. In fact, Nikodem Bartnik decided to create his own Dremel-based machine constructed out of 3D-printed parts and aluminum profiles. 

Electronics include an Arduino Uno and CNC stepper shield running GRBL for control, along with some NEMA 17 steppers and motor drivers, a relay for the Dremel, and a 12V / 30A power supply.

As with many other projects, his build went through several iterations, but the final results—seen in the video below—are quite good. The machine, which only cost him around $300, is able to mill MDF and acrylic.

If you’d like to make your own, Bartnik outlines his design in the first video below, then shows how to use it in the second. 

It isn’t a unique idea, but we liked [Eric Wiemers’s] take on the classic animated skull for Halloween. In addition to showing you the code and the wiring, the video spends some time discussing what the audio looks like and what has to happen to get it into a format suitable for the Arduino. You can see the spooky video, below.

Of course, this is also a 3D printing project, although the skull is off-the-shelf. We wondered if he felt like a brain surgeon taking the Dremel to the poor skull. To fix the two parts of the device, he used brass threaded inserts that are heat set, something we’ve seen before, but are always surprised we don’t see more often.

Of course, the project uses a servo. We may have missed it but other than freezing the video, we didn’t see the Arduino source code online. It isn’t much code, though, so typing it from the video is an option. The schematic is a little easier to read when you realize the top part is the schematic and the bottom part is the “as built” layout.

We are glad this skull doesn’t taunt us with our time remaining like some we’ve seen. We’ve seen this done with fewer parts, by the way, and you can compare the videos to see how different the circuits respond.

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