Instructables user [lingib] made a clever and inexpensive pen arm plotter that uses plastic rulers for arms. An inspiring sight for anyone without a bunch of robot parts lying around,
The electronics are straightforward, with an Arduino UNO and a pair of Easy Drivers to control NEMA17 stepper motors connected to robot wheels, which serve as hubs for the rulers. At the end of the arms, an SG90 micro servo raises and lowers the pen as commanded, shoving the whole pen assembly off the paper with its horn—an elegant solution to an age-old drawbot problem. He even wrote wrote a custom Processing program that allows him to control the plotter from his desktop
[lingib]’s experimented with different kinds of drawing machines, including a drum plotter (video after the break), a V-plotter, as well as a rolling drawbot.
If you wanted to name a few things that hackers love, you couldn’t go wrong by listing off vintage console controllers, the ESP system-on-chip platform, and pocket tools for signal capture and analysis. Combine all of these, and you get the ESP32Thang.
At its heart, the ESP32Thang is based around a simple concept – take an ESP32, wire up a bunch of interesting sensors and modules, add an LCD, and cram it all in a NES controller which helpfully provides some buttons for input. [Mighty Breadboard] shows off the device’s basic functionality by using an RFM69HW module to allow the recording and replay of simple OOK signals on the 433 MHz band. This is a band typically used by all sorts of unlicenced radio gear – think home IoT devices, wireless doorbells and the like. If you want to debug these systems when you’re out and about, this is the tool for you.
This is a fairly straightforward build at the lower end of complexity, but it gets the job done with style. The next natural step up is a Raspberry Pi with a full software defined radio attached, built into a Nintendo DS. If you build one, be sure to let us know. This project might serve as some inspiration.
With the wide availability of SPI and I2C modules these days, combined with the ease of programming provided by the Arduino environment, this is a project that just about any hacker could tackle after passing the blinking LED stage. The fact that integrating such hardware is so simple these days is truly a testament to the fact that we are standing on the shoulders of giants.
Electric gates can be an excellent labor-saving device, allowing one to remain in a vehicle while the gate opens and closes by remote activation. However, it can become somewhat of a hassle juggling the various remotes and keyfobs required, so [bredman] devised an alternative solution – controlling an electric gate over the mobile network.
20 years ago, this might have been achieved by wiring a series of relays up to the ringer of a carphone. These days, it’s a little more sophisticated – a GSM/GPRS module is connected to an Arduino Nano. When an incoming call is detected, the gate is opened. After a 3 minute wait, the gate is once again closed.
[bredman] suffered some setbacks during the project, due to the vagaries of working with serial on the Arduino Nano and the reset line on the A6 GSM module. However, overall, the gate was a simple device to interface with, as like many such appliances, it has well-labelled and documented pins for sending the gate open and close signals.
[bredman] was careful to design the system to avoid unwanted operation. The system is designed to always automatically close the gate, so no matter how many times the controller is called, the gate will always end up in a closed state. Special attention was also paid to making sure the controller could gracefully handle losing connection to the mobile network. It’s choices like these that can make a project much more satisfying to use – a gate system that constantly requires attention and rebooting will likely not last long with its users.
Overall, it’s a great project that shows how accessible such projects are – with some carefully chosen modules and mastery of serial communications, it’s a cinch to put together a project to connect almost anything to the Internet or mobile networks these days. For a different take, check out this garage door opener that logs to Google Drive.
Museum exhibits are difficult to make, and they’re always breaking down; especially the interactive ones. This is a combination of budget, building a one-off, and the incredibly harsh abuse they take from children.
My first exhibit is an interactive laser show that turns waveforms from music into laser patterns, and different types of music have very different patterns. I knew from talking to the museum staff that industrial buttons were a necessity, but it turns out that industrial buttons are made under the assumption that tiny creatures won’t be constantly mashing, twisting, and (ew ew ew) licking the buttons. After a while, the buttons (and poor knob) were trashed.
The button face has been removed, and the knob is spinning freely.
Buttons at toddler level are in a vulnerable position.
The second exhibit is also interactive, but in this case it’s just a simple button that turns on a thing for a while, then shuts it off. You can read more about the Periodic Table of Motion on the project page. Here I thought; let’s use capacitive touch, put the sensor behind two layers of acrylic for protection, and then there won’t be any moving parts to break. I built a bunch of units, tested it for weeks, then installed it. Instant failure despite my diligence.
Something is different about the installation from my test environment. It might be the second layer of acrylic contributing. Maybe it’s the power supply and a strange ground issue. Maybe the room’s fluorescent lights are creating an electromagnetic field that is interrupting the sensor, or the carpet is causing static buildup that is somehow causing the midichlorians to reverse polarity and discharge through the base plate of prefabulated aluminite. In some of the cells, the button doesn’t work. In other cells it is extremely sensitive. In one column of the table (columns share a common piece of acrylic among 5 cells), a single touch will trigger all 5.
The circuit is an ATtiny with a 2.2M resistor between two pins, one of which connects via a short wire to a soldered connection to a piece of copper tape on the underside of an acrylic piece. The ATtiny is using the capsense library, which has features for automatic recalibration. Because of the way it is installed, I can’t reprogram them to adjust their sensitivity while inside the enclosure, so tweaking them post-install is not an option. I thought I could isolate the problem and use an existing capacitive touch sensor breakout of the AT42QT1010 hooked up to just power, but it had the exact same issue, meaning it’s either the power supply, the enclosure, or the room.
Side-by-side tests of copper tape+Arduino and AT42QT1010 had similar problems.
There are three paths I can go down now:
Find the problem and solve it
Switch to a photoresistor
Petition Hackaday for a better solution
Finding the problem and solving it will be a long and difficult path, especially since the museum environment is somehow and inexplicably different from the test environment. The photoresistor option has promise; when the user puts their hand over the paper button the light level changes. Some early testing indicates that it is easy to detect instantaneous change, and a trailing average and adjusting threshold make it robust enough for changing lighting conditions throughout the day. Further, it’s a simple change to the code, and the existing circuit board will accommodate the adjustment.
As for the third option…
What have you done for child-compatible touch interfaces that are robust enough to handle uncertain environments and harsh abuse? What buttons, knobs, and other interactive elements have you used?
It’s always an exciting moment when an event schedule is released, and since events in our community don’t come much larger than this August’s SHA Camp in the Netherlands, you can imagine that the announcement of their schedule of lectures of talks is something of an event in itself. The event runs over five days, and you can browse the schedule itself to make your picks.
The SHA team have made their own picks, but with so many stages and speakers they are only a tiny selection. Running a Hackaday eye over the schedule, here are the ones that caught our eye.
[dennisdebel]’s lecture, from glass fiber to fiber glass noodles caught our eye. Using mung bean vermicelli, or ‘glass noodles’, for data transmission, is not something you hear about every day.
If you are a regular at European hardware hacker camps, you may have encountered the chiptune extravaganza performances of [Gasman], otherwise known as [Matt Westcott]. Hie lecture, Zero to chiptune in one hour, will create, from scratch, a chiptune cover version of a pop song chosen by the audience, all on a Sinclair ZX Spectrum.
The Hackeboy handheld game console is a project from a small Hamburg-based indie game label.[Axel Theilmann] describes the process of building the handheld console they always dreamed of.
One of the final lectures of the event comes from [Niek Blankers], and will describe in detail the SHA2017 badge. How it was designed, and showcasing what some of the attendees will by then have managed to do with it.
Finally, if you want to see a Hackaday scribe talking about fun and games with little plastic bags of parts, you could do worse than seeking out From Project To Kit, all you will need to know about turning your personal electronic projects into a kit business.
Watch this space for more from SHA Camp as we get it. Meanwhile you can take a look at our coverage of the SHA2017 badge launch.
Humanity is a planetwide force. We have the power to change our weather. We have the power to change the shape of the land. We have the power to selectively wipe a species from this earth if we choose. We’ve had this power for a while and we’re still coming to terms with it. Many of us even deny it.
With such power, what do we do? We have very few projects which are in line with our ability. Somewhere in the past few years, I feel like most of us have lost our audacity. We’ve culturally come to appreciate the safe bet too much. We pull the dreamers and doers down. We want to solve the small problems first, and see if we have time for the big problems later. We don’t dream big enough, and there is zero reason for this hesitation. We could leverage our planetwide power for planetwide improvements. Nothing is truly stopping us. No law, no government, nothing.
To put it simply, as far as technology goes, everything is still low-hanging fruit. We’ve barely done anything. Even some of our greatest accomplishments can happen randomly in nature. We’ve not left our planet in any numbers or for any length of time. Our cities are disorganized messes. In every single field today, the unexplored territory is orders larger than the explored. Yet despite this vast territory, there are very few explorers. People want to optimize the minutia of life. A slightly faster processor for a slightly smaller phone. It’s okay.
Yet that same small optimization applied to a larger effort could have vast positive impact. Those same microprocessors could catalog our planet or drive probes into space. The very same efforts we spend on micro upgrades could be leveraged if we just look at the bigger picture then get out of our own way. All that is lacking is ambition. Money, time, skill, industry, and people are all there, waiting. We have the need for and have the resources to support ten thousand Elon Musks, not just the one.
Big projects make us bigger than our cellphones and Facebook. When you see a rocket launch into the sky, suddenly, “the world” becomes, simply, “a world.” Order of magnitude improvements reduce the order of our perception of previously complex problems. They should be our highest goal. Whatever field you’re in, you should be trying to be ten times better than the top competitor.
However, there are some societal changes that have to occur before we can.
Sometimes it starts with a 555 timer and an op-amp. Other times with a small microcontroller. But the timing’s not so great and needs a dedicated timing crystal circuit. And maybe some more memory, and maybe the ATtiny should be swapped out for some 74LS-series chips. And now of course it needs video output too. Before you know it, you’re staring at a 40-chip computer that hearkens back to a simpler, yet somehow more complex, time of computing. At least that’s where [Marcel] is with his breadboard computer based on 1970s-era chips.
For what it does, this homebrew computer is relatively simple and straightforward. It gets 8 bits of processing power from 34 TTL chips. Another 6 round out the other features needed for the computer to operate. It is capable of rendering 64 colors in software and has more than enough memory for a computer of this sort. So far the only recurring problem [Marcel] has had has been with breadboard fatigue, as some of the chips keep popping out of the sockets.
This is a great project for anyone interested in homebrew or 8-bit computing, partially because of some of the self-imposed limitations that [Marcel] imposed on himself, like “only chips from the 70s”. It’s an impressive build on its own and looks to get much better since future plans call for a dedicated PCB to solve the issue with the worn-out breadboards. If you’re already invested in a project like this, don’t forget that the rabbit hole can go a little deeper: you can build a computer out of discrete transistors as well.
