Hackaday Podcast 138: Breakin’ Bluetooth, Doritos Rockets, Wireless Robots, And Autonomous Trolling

Hackaday editors Elliot Williams and Mike Szczys peruse the great hardware hacks of the past week. There’s a robot walker platform that wirelessly offloads motor control planning to a computer. We take a look at automating your fishing boat with a trolling motor upgrade, building the Hoover dam in your back yard, and playing Holst’s Planets on an army of Arduini. Make sure you stick around until the end as we stroll through distant memories of Gopher, and peek inside the parking garages of the sea.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (60 MB or so.)

Continue reading “Hackaday Podcast 138: Breakin’ Bluetooth, Doritos Rockets, Wireless Robots, And Autonomous Trolling”

an image of the graffomat at work

Automate Your Graffiti With The Graffomat!

In Banksy’s book, Wall and Piece, there is a very interesting quote; “Imagine a city where graffiti wasn’t illegal, a city where everybody could draw whatever they liked…”. This sounds like it would be a very exciting city to live in, except for those of us who do not have an artistic bone in their body. Luckily, [Niklas Roy] has come up with the solution to this problem; the Graffomat, a spray can plotter.

The Graffomat is, in its creator’s own words, a “quick and dirty graffiti plotter.” It is constructed primarily from wood and driven by recycled cordless drills that pulls string pulleys to move the gantry.  The Arduino Nano at the heart of the Graffomat can be controlled by sending coordinates over serial. This allows for the connection of an SD card reader to drip-feed the machine, or a computer to enable real-time local or over-the-internet control.

We are especially impressed with how [Niklas] handled positional tracking. The cordless drills were certainly not repeatable like a stepper motor, as to allow for open-loop control. Therefore, the position of the gantry and head needed to be actively tracked. To achieve this, the axes are covered with black and white striped encoder strips, that is then read by a pair of phototransistors as the machine moves along. These can then be paired with the homing switches in the top left corner to determine absolute position.

Graffomat is not the first automated graffiti machine we’ve covered. Read here about the robot that painted murals by climbing smokestacks in Estonia. 

Continue reading “Automate Your Graffiti With The Graffomat!”

A Stress Monitor Designed Specifically To Help You Work From Home

There are quite a bit of mixed emotions regarding working from home. Some people love it and are thriving like they haven’t before, but others are having a bit of a hard time with it all. [Brandon] has been working from home for the last 12 years, but even after so many years of managing this type of work culture, he admits that it can still be a little stressful. He says he doesn’t take enough time in between tasks to simply relax and to breathe a little and the day-to-day minutia of his work can drive his stress level up if he doesn’t take some time to calm himself. He figured he could make something to monitor his stress level and remind himself to take a break and the results are pretty impressive.

He develops a system to monitor his heart rate and the ambient noise level in his room and uses these metrics as a measure of stress. If his heart rate or the ambient noise level goes above a certain threshold, then he sends himself a text message reminding himself to relax and take a break. You’ve probably seen people use heart rate as a measure of stress already, but you’re probably less familiar with using sound. [Brandon] basically thought the sound sensor would detect if he starts ranting for prolonged periods of time or if he’s in a Zoom meeting that gets too heated. We thought that was pretty neat.

[Brandon] used an off-the-shelf chest strap heart rate monitor to save himself a bit of time in trying to build his own. The device sends heart rate data to an nRF52840 over Bluetooth and then pushes the data to the cloud using a Blues Wireless Notecard. The Notecard also offers data encryption which gave [Brandon] some added peace of mind knowing his biometric data wasn’t floating around in the cloud without any sort of protection. This certainly isn’t medical-grade encryption, but it gave him a bit of comfort, nonetheless. All that data is processed in his custom-designed web app and when the appropriate thresholds are reached, he sends a text message to himself using Twilio reminding him to relax and unwind for a bit.

For his next iteration, [Brandon] might try making his own heart rate monitor. But until then, stay safe everybody, and remember to take a break whenever you need it.

Continue reading “A Stress Monitor Designed Specifically To Help You Work From Home”

Permanent Artificial Hearts: Long-Sought Replacements May Not Be Far Away

The number of artificial prosthetic replacement parts available for the human body is really quite impressive. From prosthetic eyes to artificial hips and knees, there are very few parts of the human body that can’t be swapped out with something that works at least as well as the original, especially given that the OEM part was probably in pretty tough shape in the first place.

But the heart has always been a weak spot in humans, in part because of the fact that it never gets to rest, and in part because all things considered, we modern humans don’t take really good care of it. And when the heart breaks down past the point where medicine or surgery can help, we’re left with far fewer alternatives than someone with a bum knee would face. The fact is that the best we can currently hope for is a mechanical heart that lets a patient live long enough to find a donor heart. But even then, tragedy must necessarily attend, and someone young and healthy must die so that someone else may live.

A permanent implantable artificial heart has long been a goal of medicine, and if recent developments in materials science and electrical engineering have anything to say about it, such a device may soon become a reality. Heart replacements may someday be as simple as hip replacements, but getting to that point requires understanding the history of mechanical hearts, and why it’s not just as simple as building a pump.

Continue reading “Permanent Artificial Hearts: Long-Sought Replacements May Not Be Far Away”

DIY PECS Board Uses Pictures To Communicate

One way of communicating with autistic and non-verbal people is through the use of a Picture Exchange Communication System or PECS board, which they can use to point out what they need or want throughout the day. However, the commercial versions of these boards have their share of problems — they’re expensive, and they’re fairly rigid as far as the pictures go. [Alain Mauer] has created an open-source PECS board that is far more personalized, and has audio to boot.

The number one requisite here is sturdiness, as [Alain]’s son [Scott] has already smashed two smartphones and a tablet. [Alain] went with a laser-cut MDF enclosure that should last quite a while. Inside is an Arduino Pro Mini and a DF Player Mini that plays corresponding clips from a micro SD card whenever [Scott] presses a button on the 16-key copper foil capacitive keypad. This PECS board is smart, too — it will sound a turn-me-off reminder after a few minutes of inactivity, and issue audible low battery warnings.

So far, [Scott] is responding better to photographs of objects than to drawings. Watch him interact with the board after the break.

This is far from the first thing [Alain] has built to help [Scott]. Be sure to check out this Pi-based media player built to engage and not enrage. Continue reading “DIY PECS Board Uses Pictures To Communicate”

Hackaday Podcast 126: Cable 3D-Scanner, Tesla Charger Robot, Ultrasonic Anemometer, And A Zoetrope

Hackaday editors Elliot Williams and Mike Szczys dive into a week of exceptional hacks. Tip-top of the list has to be the precision measuring instrument that uses a cable spooling mechanism. There’s news that the Starlink base station firmware has been dumped and includes interesting things like geofencing for the developer modes. We saw a garage robot that will plug in your electric vehicle if you’re the forgetful sort. And we close up by talking about heavier-than-air helium airships and China’s Mars rover.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (55 MB or so.)

Places to follow Hackaday podcasts:

Continue reading “Hackaday Podcast 126: Cable 3D-Scanner, Tesla Charger Robot, Ultrasonic Anemometer, And A Zoetrope”

This Week In Security: Print Nightmare Continues, Ransomware Goes Bigger, And ATM Jackpots!

For the second time, Microsoft has attempted and failed to patch the PrintNightmare vulnerability. Tracked initially as CVE-2021-1675, and the second RCE as CVE-2021-34527. We warned you about this last week, but a few more details are available now. The original reporter, [Yunhai Zhang] confirms our suspicions, stating on Twitter that “it seems that they just test with the test case in my report”.

Microsoft has now shipped an out-of-band patch to address the problem, with the caveat that it’s known not to be a perfect fix, but should eliminate the RCE element of the vulnerability. Except … if the server in question has the point and print feature installed, it’s probably still vulnerable. And to make it even more interesting, Microsoft says they have already seen this vulnerability getting exploited in the wild. Continue reading “This Week In Security: Print Nightmare Continues, Ransomware Goes Bigger, And ATM Jackpots!”