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Have you built a 3D scanner yet? There’s more than one way to model those curves and planes, but the easiest may be photogrammetry — that’s the one where you take a bunch of pictures and stitch them into a 3D model. If you build a scanner like [Brian Brocken]’s that does almost everything automatically, you might consider starting a scan-and-print side hustle.

This little machine spins objects 360° and triggers a Bluetooth remote tethered to an iPhone. In automatic mode, it capture anywhere from 2-200 pictures. There’s a mode for cinematic shots that shoots video of the object slowly spinning around, which makes anything look at least 35% more awesome. A third mode offers manual control of the turntable’s position and speed.

An Arduino UNO controls a stepper that moves the turntable via 3D printed-in-place bearing assembly. This project is a (vast) improvement over [Brian]’s hand-cranked version that we looked at over the summer, though both are works of art in their own right.

Our favorite part aside from the bearing is the picture-taking process itself. [Brian] couldn’t get the iPhone to play nice with HC-05 or -06 modules, so he’s got the horn of 9g servo tapping the shutter button on a Bluetooth remote. This beautiful beast is wide open, so fire up that printer. You can watch the design and build process of the turntable after the break.

Want to scan some really tiny things? Make a motorized microscope from movie machines.

In the midst of striking for climate change awareness, you may need some extra hands. That’s what [Anred Zynch] thought when they built Strettexter, the text-spraying writing robot that sprays onto streets.

The machine is loaded with 8 spray cans placed into a wooden box (a stop line with a wooden ledge to prevent the cans from falling out) and is fixed on top of a skateboard. It uses a PWN/Servo shield soldered onto an Arduino Uno connected to 8 servo motors (TowerPro SG90s) to control each of the spray bottles. A table converts every character into 5×8 bit fonts to fit the size of the spraying module. The device also includes a safety switch, as well as an encoder for measuring the horizontal distance traveled.

The Strettexter is activated by pulling on the skateboard once it’s been set up and connected to power (for portability, it uses a 8000mAh power bank). In its current configuration, the words stretch out pretty long, but some additional testing will probably lead to better results depending on the constraints of your canvas. The shorter the words, the more difficult it is for the white text to be legible, since there is significant spacing between printed bits.

We don’t condone public vandalism, so use this hack at your own discretion.

[Thanks neiß for the tip!]

Phones are pretty great. Used as telephones, they can save us from bad situations and let us communicate while roaming freely, for the most part. Used as computers, they often become time-sucking black holes that can twist our sense of self and reality. Assuming they pick up when you call, phones are arguably a good thing for kids to have, especially since you can hardly find a payphone these days. But how do you teach kids to use them responsibly, so they can still become functioning adults and move out someday? [Jaychouu] believes the answer is inside of a specialized lockbox.

This slick-looking box has a solenoid lock inside that can be unlocked via a keypad, or remotely via the OBLOQ IoT module. [Jaychouu] added a few features that drive it out of Arduino lockbox territory. To prevent latchkey children from cheating the system and putting rocks (or nothing at all) in the box, there’s a digital weight sensor and an ultrasonic sensor that validate the credentials of the contents and compare them with known values.

Want a basic lockbox to keep your phone out of reach while you work? Here’s one with a countdown timer.

Phones are pretty great. Used as telephones, they can save us from bad situations and let us communicate while roaming freely, for the most part. Used as computers, they often become time-sucking black holes that can twist our sense of self and reality. Assuming they pick up when you call, phones are arguably a good thing for kids to have, especially since you can hardly find a payphone these days. But how do you teach kids to use them responsibly, so they can still become functioning adults and move out someday? [Jaychouu] believes the answer is inside of a specialized lockbox.

This slick-looking box has a solenoid lock inside that can be unlocked via a keypad, or remotely via the OBLOQ IoT module. [Jaychouu] added a few features that drive it out of Arduino lockbox territory. To prevent latchkey children from cheating the system and putting rocks (or nothing at all) in the box, there’s a digital weight sensor and an ultrasonic sensor that validate the credentials of the contents and compare them with known values.

Want a basic lockbox to keep your phone out of reach while you work? Here’s one with a countdown timer.

LEDs and blinky projects are great, and will likely never fade from our favor. But would you look at this sweeping beauty? This mesmerizing display is made from 36 micro servos with partial Popsicle sticks pasted on the arms. After seeing a huge display with 450 servos at an art museum, [Doug Domke] was inspired to make a scaled-down version.

What [Doug] didn’t scale down is the delightful visuals that simple servo motion can produce. The code produces a three-minute looping show that gets progressively more awesome, and you can stare at that after the break. Behind the pegboard, a single, hardworking Arduino Uno controls three 16-channel PWM controllers that sweep the servos. We like to imagine things other than Popsicle sticks swirling around, like little paper pinwheels, or maybe optical illusion wheels for people with strong stomachs.

You won’t see these in the video, but there are five ultrasonic sensors mounted face-up on the back of the pegboard. [Doug] has optional code built in to allow the servo sticks to follow hand movement. We hope he’ll upload a demo of that feature soon.

Servos can be hypnotic as well as helpful, as we saw in this 114-servo word clock.

Via Arduino blog

Many of us have considered buying an air hockey table, but are put off by the price. And even if the money is there, those things take up a lot of space. How often are you really going to use it?

This DIY air hockey table is the answer. It’s big enough to be fun, but small and light enough to easily stow away in the off-season. At ~$50, it’s a cheap build, provided you have a vacuum cleaner that can switch to blower mode. The strikers, goals, corner guards, and scoreboard enclosure are all 3D-printed, while the pucks and playfield are laser-cut acrylic. [Technovation] glued acrylic feet to the strikers to help them last longer.

The scoreboard is an Arduino Uno plus an LCD that changes color to match the current winner. Scoring must be entered manually with button presses, but we think it would be fairly easy to detect a puck in the goal with a force or weight sensor or something. For now, the RGB LEDs around the edge are controlled separately with a remote. The ultimate goal is to make the Arduino do it. Shoot past the break and cross-check it out.

Already have a table? Had it so long, no one will play you anymore? Build yourself a robotic opponent.

Have you shopped for an appliance lately? They’re all LEDs, LEDs everywhere. You might say that manufacturers are out of touch with the utility of tactile controls. [Wingletang]’s fancy new washing machine is cut from this modern cloth. While it does have a nice big knob for selecting cycles, the only indication of your selection is an LED. This isn’t an issue for [Wingletang], but it’s a showstopper for his visually impaired wife.

They tried to make tactile signposts for her most-used cycles with those adhesive rubber feet you use to keep cabinet doors quiet. But between the machine’s 14(!) different wash cycles and the endlessly-rotating selector knob, the tactile map idea was a wash. It was time to make the machine talk.

For his very first microcontroller project, [Wingletang] designed a completely non-invasive and totally awesome solution to this problem. He’s using LDRs arranged in a ring to detect which LED is lit. Recycled mouse pad foam and black styrene keep ambient light from creating false positives, and double as enclosure for the sensor and support boards. As [Mrs. Wingletang] cycles through with the knob, an Arduino clone mounted in a nearby project box determines which program is selected, and a Velleman KA02 audio shield plays a recorded clip of [Wingletang] announcing the cycle number and description.

The system, dubbed SOAP (Speech Output Announcing Programmes), has been a great help to [Mrs. Wingletang] for about the last year. Watch her take it for a spin after the break, and stick around for SOAP’s origin story and walk-through videos.

It’s baffling that so few washers and dryers let you know when they’re finished. Don’t waste your time checking over and over again—Laundry Spy waits for the vibrations to end and sends you a text.

 

These days, you could be forgiven for thinking driving an LCD from a microcontroller is easy. Cheap displays have proliferated, ready to go on breakout boards with controllers already baked in. Load up the right libraries and you’re up and running in a matter of minutes. However, turn your attention to trying to drive a random LCD you’ve yanked out of a piece of old equipment, and suddenly things get harder. [Ivan Kostoski] was in just such a position and decided to get down to work.

[Ivan]’s LCD was a 320×240 STN device salvaged from an old tape library. The display featured no onboard controller, and the original driver wasn’t easily repurposed. Instead, [Ivan] decided to drive it directly from an Arduino Uno.

This is easier said than done. There are stringent timing requirements that push the limits of the 8-bit platform, let alone the need for a negative voltage to drive the screen and further hardware to drive the backlight. These are all tackled in turn, with [Ivan] sharing his tips to get the most flexibility out of the display. Graphics and text modes are discussed, along with optimizations that could be possible through the varied use of available RAM and flash.

The code is available on Github. If you need inspiration for your own controllerless LCD driver. [Ben Heck] has done similar work too, using FPGA grunt to get the job done.

Many of the projects we feature on Hackaday are motivated by pure greed. Not on the part of the hacker, mind you; but rather the company that’s charging such an outrageous price for a mass produced item that somebody decides they can do the same thing cheaper as a one-off project. Which is precisely how [Bryan Kevan] ended up building his own carbon fiber tube wrapping machine. Not only do the finished tubes look fantastic, but they cost him a fraction of what even the “cheap” commercial ones cost.

The principle behind producing the tubes is really pretty simple: carbon fiber ribbon (or “tow”, in the official parlance) gets wrapped around a rotating mandrel, ideally in interesting patterns, and epoxy is added to bind it all together. When it’s hardened up, you slide the new carbon fiber tube off the mandrel and away you go building a bike frame or whatever it is you needed light and strong tubes for. You could even do it by hand, if you had enough patience.

[Bryan] had done it by hand before, but was looking for a way to not only automate the process but make the final product a bit more uniform-looking. His idea was to rotate a horizontal PVC pipe as his mandrel, and move a “car” carrying the carbon fiber ribbon back and forth along its length. The PVC pipe just needs to rotate along its axis so he figured that would be easy enough; and using a GT2 belt and some pulleys, getting the carbon-laying car moving back and forth didn’t seem like much of a challenge either.

The frame of the winder is built from the hacker’s favorite: 20/20 aluminum extrusion. Add to that an Arduino Uno, two stepper motors with their appropriate drivers, and the usual assortment of 3D printed odds and ends. [Bryan] says getting the math figured out for generating interesting wrap patterns was a bit tricky and took a fair amount of trial and error, but wasn’t a showstopper. Though we’d suggest following his example and using party ribbon during testing rather than the carbon stuff, as producing a few bird nests at the onset seems almost a guarantee.

One of the trickiest parts of the project ended up being removing the carbon fiber tubes from the PVC mandrel once they were done. [Bryan] eventually settled on a process which involved spraying the PVC with WD-40, wrapping it in parchment paper, and then using a strip of 3M blue painter’s tape to keep the parchment paper from moving. If you can toss the whole mandrel in the freezer after wrapping to shrink it down a bit, even better.

So was all this work worth it in the end? [Bryan] says he was originally looking at spending up to $70 USD per foot for the carbon fiber tubes he needed for his bike frame, but by buying the raw materials and winding them himself, he ended up producing his tubes for closer to $3 per foot. Some might question the strength and consistency of these DIY tubes, but for a ~95% price reduction, we’d be willing to give it a shot.

Years ago we covered a Kickstarter campaign for a very similar carbon winder. Probably due to the relatively limited uses of such a gadget, the winder didn’t hit the funding goal. But just like the current wave of very impressive homebrew laser cutters, the best results might come from just building the thing yourself.

Taking pictures in the 21st century is incredibly easy. So easy in fact that most people don’t even own a dedicated camera; from smartphones to door bells there are cameras built into nearly electronic device we own. So in this era of ubiquitous photography, you might think that a very slow and extremely low resolution camera wouldn’t be of interest. Under normal circumstances that’s probably true, but this single pixel camera built by [Tucker Shannon] is anything but normal.

At the heart of his unusual camera is the TCS34725 RGB color sensor from Adafruit which receives a tightly focused beam of incoming light by way of a 3D printed enclosure and a 3mm OD aluminum tube. This allows an Arduino Uno to determine the color of this tiny slice of light, making up a single pixel of the final color image. [Tucker] notes that you could even swap the color sensor out for a simple photocell if you don’t mind a black & white image at the end of the process.

In either event, once the light has been analyzed the sensor is repositioned autoturret-style by way of dual BYJ-48 stepper motors. This process continues on, spiraling outwards until the whole image is stitched together from these individual readings

Now compared to the camera in your phone, the resulting image might be a bit underwhelming. We’d say it’s a bit like looking at a digital picture on an 8 bit computer, but in truth even that might be overly generous. But even if it isn’t as crisp as modern eyes would like there’s no question that it’s certainly a recognizable image, which is all [Tucker] was shooting for.

Of course if your optical frugality is such that even this low-resolution camera is too sharp for your tastes, we’ve seen a similar concept  using a roof-mounted solar array.



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