Old Robotic Vacuum Gets A New RC Lease On Life

December 22, 2022 by Dan Maloney 8 Comments

To our way of thinking, the whole purpose behind robotic vacuum cleaners is their autonomy. They’re not particularly good at vacuuming, but they are persistent about it, and eventually get the job done with as little human intervention as possible. So why in the world would you want to convert a robotic vacuum to radio control?

For [Lucas], the answer was simple: it was a $20 yard sale find, so why not? Plus, he’s got some secret evil plan to repurpose the suckbot for autonomous room mapping, which sounds like a cool project that would benefit from a thorough knowledge of this little fellow’s anatomy and physiology. The bot in question is a Hoover Quest. Like [Lucas] we didn’t know that Hoover made robotic vacuums (Narrator: they probably don’t) but despite generally negative online reviews by users, he found it to be a sturdily built and very modular and repairable unit.

After an initial valiant attempt at reverse engineering the bot’s main board — a project we encourage [Lucas] to return to eventually — he settled for just characterizing the bot’s motors and sensors and building his own controller. The Raspberry Pi Zero he chose may seem like overkill, but he already had it set up to talk to a PS4 game controller, so it made sense — right up until he released the Magic Smoke within it. A backup Pi took the sting out of that, and as the brief video below shows, he was finally able to get the bot under his command.

[Lucas] has more plans for his new little buddy, including integrating the original sensors and adding new ones. Given its intended mission, we’d say a lidar sensor would be a good addition, but that’s just a guess. Whatever he’s got in store for this, we’re keen to hear what happens.

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PCB Bring-Up Hack Chat

April 14, 2020 by Dan Maloney No comments

Join us on Wednesday, April 15 at noon Pacific for the PCB Bring-Up Hack Chat with Mihir Shah and Liam Cadigan!

The printed circuit design process is pretty unique among manufacturing processes. Chances are pretty good that except for possibly a breadboard prototype, the circuit that sits before you after coming back from assembly has only ever existed in EDA software or perhaps a circuit simulator. Sure, it’s supposed to work, but will it?

You can — and should — do some power-off testing of new boards, but at some point you’re going to have to flip the switch and see what happens. The PCB bring-up process needs to be approached carefully, lest debugging any problems that crop up become more difficult than need be. Mihir and Liam from inspectAR will discuss the bring-up process in depth, offering tips and tricks to make things go as smoothly as possible, as well as demonstrating how the inspectAR platform can fit into that process, especially with teams that are distributed across remote sites. If your board releases the Magic Smoke, you’ll want to know if it’s your design or an assembly issue, and an organized bring-up plan can be a big help.

Note: Liam will be doing a simulcast web demo of inspectAR via Zoom.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, April 15 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

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Epoxy Fix For A Combusted PCB

September 26, 2018 by Dan Maloney 29 Comments

When the Magic Smoke is released, chances are pretty good that you’ve got some component-level diagnosis to do. It’s usually not that hard to find the faulty part, charred and crusty as it likely appears. In that case, some snips, a new non-crusty part, and a little solder are usually enough to get you back in business.

But what if the smoke came not from a component but from the PCB itself? [Happymacer] chanced upon this sorry situation in a power supply for an electric gate opener. Basking in the Australian sunshine for a few years, the opener started acting fussy at first, then not acting at all. Inspection of its innards revealed that some unlucky ants had shorted across line and neutral on the power supply board, which burned not only the traces but the FR4 of the board as well. Rather than replace the entire board, [Happymacer] carefully removed the carbonized (and therefore conductive) fiberglass and resin, leaving a gaping hole in the board. He fastened a patch for the hole from some epoxy glue; Araldite is the brand he used, but any two-part epoxy, like JB Weld, should work. One side of the hole was covered with tape and the epoxy was smeared into the hole, and after a week of curing and a little cleanup, it was ready for duty. The components were placed into freshly drilled holes, missing traces were replaced with wire, and it seems to be working fine.

This seems like a great tip to keep in mind for when catastrophe strikes your boards. There are more extreme ways to do it, of course, but perhaps none so flexible. After all, epoxy is versatile stuff.

Arduino Trivia Box Is A Gift Unto Itself

December 29, 2017 by Tom Nardi 3 Comments

There’s something about impressing strangers on the Internet that brings out the best in us. Honestly, we wouldn’t be able to run this site otherwise. A perfect example of this phenomenon is the annual Reddit Secret Santa, where users are challenged to come up with thoughtful gifts for somebody they’ve never even met before.

For his entry into this yearly demonstration of creativity, [Harrison Pace] wanted to do something that showcased his improving electronic skills while also providing something entertaining to the recipient. So he came up with a box of goodies which is unlocked by the successful completion of a built-in trivia game tailored around their interests. If this is how he treats strangers, we can’t wait to see what he does for his friends.

Hardware packed into the lid so the box itself remains empty.

There’s quite a bit of hardware hidden under the hood of this bedazzled gift box. The primary functions of the box are handled by an Arduino Nano; which runs the trivia game and provides user interaction via a 16×2 LCD, three push buttons, and a buzzer. Once the trivia game is complete, a servo is used to unlock the box and allow the recipient access to the physical gifts.

But that’s not the only trick this box has hidden inside. Once the main trivia game is complete, a ESP8266 kicks into action and advertises an access point the user can connect to. This starts the second level of challenges and gifts, which includes a code breaking challenge and gifted software licenses.

The project wasn’t all smooth sailing though. [Harrison] admits that his skills are still developing, and there were a few lessons learned during this project he is unlikely to forget in the future. Some Magic Smoke managed to escape when he connected his 5V Arduino directly to the 3.3V ESP8266, but at least it was a fairly cheap mistake and he had spares on hand to get the project completed anyway.

This project is reminiscent of reverse geocache boxes which only open when moved to a certain location, but the trivia aspect makes it perfect even for those of us who don’t want to put pants on just to receive our Internet gifts.

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Fail Of The Week: How I Killed The HiPot Tester

December 29, 2016 by Jenny List 18 Comments

Have you ever wired up a piece of test equipment to a circuit or piece of equipment on your bench, only to have the dreaded magic smoke emerge when you apply power? [Steaky] did, and unfortunately for him the smoke was coming not from his circuit being tested but from a £2300 Clare H101 HiPot tester. His write-up details his search for the culprit, then looks at how the manufacturer might have protected the instrument.

[Steaky]’s employer uses the HiPot tester to check that adjacent circuits are adequately isolated from each other. A high voltage is put between the two circuits, and the leakage current between them is measured. A variety of tests are conducted on the same piece of equipment, and the task in hand was to produce a new version of a switch box with software control to swap between the different tests.

This particular instrument has a guard circuit, a pair of contacts that have to be closed before it will proceed. So the switch box incorporated a relay to close them, and wiring was made to connect to the guard socket. At first it was thought that the circuit might run at mains voltage, but when it was discovered to be only 5V the decision was made to use a 3.5mm jack on the switch box. Inadvertently this was left with its sleeve earthed, which had the effect of shorting out a DC to DC converter in the HiPot tester and releasing the smoke. Fortunately then the converter could be replaced and the machine brought back to life, but it left questions about the design of the internal circuit. What was in effect a logic level sense line was in fact connected to a low current power supply, and even the most rudimentary of protection circuitry could have saved the day.

We all stand warned to be vigilant for this kind of problem, and kudos to [Steaky] for both owning up to this particular fail and writing such a good analysis of it.

Our Fail Of The Week series has plenty to entertain the reader who is not of a nervous disposition. This isn’t the first fail to feature a suspect bit of connector wiring, not an unexpected short or even some magic smoke.

Driving A Brushless DC Motor Sloooooooowly

April 20, 2015 by Will Sweatman 66 Comments

Driving a brushless DC (gimbal) motor can be a pain in the transistors. [Ignas] has written up a nice article not only explaining how to do just this with an Arduino, but also explaining a little bit on how the process works. He uses a L6234 Three Phase Motor Driver, but points out that there are other ways to interface the BLDC motor with the Arduino.

A warning is warranted – this is not for the faint of heart. You can easily destroy your microcontroller if you’re not careful. [Ignas] added several current limiting resistors and capacitors as advised in the application note (PDF warning) to keep things safe.

Everything worked well at high speeds, but for slower speeds the motor was choppy. [Ingus] solved this riddle by changing over to a sine wave to drive the motor. Instead of making the Arduino calculate the wave, he used a look up table.

Be sure to check out his blog for full source and schematics. There is also a video demonstrating just how slow he can make the motor move below.

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Faulty ESP8266s Release Smoke, Then Keep Working?

January 8, 2015 by Matt Freund 83 Comments

[Ray] is in a bit of a pickle. All appeared well when he began selling an ESP8266-based product, but shortly thereafter some of them got hot and let the smoke out. Not to worry, he recommends ignoring the problem since once the faulty components have vaporized the device will be fine.

The symptom lies in the onboard red power indicator LED smoking. (Probably) nothing is wrong with the LED, because upon testing the batch he discovered its current limiting resistor is sometimes a little bit low to spec. Off by a hair of, oh, call it an even 1000x.

Yep, the 4700 ohm resistor is sometimes replaced with a 4.7 ohm. Right across the power rail. That poor little LED is trying to dissipate half a watt on a pinhead. Like a sparrow trying to slow a sledgehammer, it does not end well. Try not to be too critical, pick ‘n place machines have rough days now and then too and everyone knows those reels look practically the same!

The good news is that the LED and resistor begin a thermal race and whoever wins escapes in the breeze. Soon as the connection cuts the heat issue disappears and power draw drops back to normal. Everything is fine unless you needed that indicator light. Behold – there are not many repairs you can make with zero tools, zero effort, and only a few seconds of your time.

[Ray] also recommends measuring and desoldering the resistor or LED if you are one of the unlucky few, or, if worst comes to worst, he has of course offered to replace the product too. He did his best to buy from authentic vendors and apologizes to the few customers affected. As far as he knows no one else has had this problem yet so he wanted to share it with the community here on Hackaday as soon as possible. Keep an eye out.

If you have never seen ~~smoke~~ ISO9001-certified electronics repair before, there is a short video of this particular ~~disaster~~ upgrade caught live on tape after the break.

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