Solar Flare Quiets A Quarter Of The Globe

September 18, 2022 by Al Williams 13 Comments

In the “old” days, people were used to the idea that radio communication isn’t always perfect. AM radio had cracks and pops and if you had to make a call with a radiophone, you expected it to be unreliable and maybe even impossible at a given time. Modern technology, satellites, and a host of other things have changed and now radio is usually super reliable and high-fidelity. Usually. However, a magnitude 7.9 solar flare this week reminded radio users in Africa and the Middle East that radio isn’t always going to get through. At least for about an hour.

It happened at around 10 AM GMT when that part of the world was facing the sun. Apparently, a coronal mass ejection accompanied the flare, so more electromagnetic disruption may be on its way.

The culprit seems to be an unusually active sunspot which is expected to die down soon. Interestingly, there is also a coronal hole in the sun where the solar wind blows at a higher than usual rate. Want to keep abreast of the solar weather? There’s a website for that.

We’ve pointed out before that we are ill-prepared for technology blackouts due to solar activity, even on the power grid. The last time it happened, we didn’t rely so much on radio.

Continue reading “Solar Flare Quiets A Quarter Of The Globe” →

An orange and white cat eats from a bowl with a hinged cover. The cat and the bowl are on top of an MDF platform.

Load Cells To Get The Right Pet The Right Food

September 18, 2022 by Navarre Bartz 11 Comments

If you have more than one pet, you may know how hard it is to tell how much each furry friend is eating. If you introduce prescription foods, then this minor annoyance can have a major impact on your pet’s health. Facing this dilemma, [tomasdiazwahl] set out to make a pet feeder that feeds his pets exactly what they need when they approach the feeder.

Using the ever-popular Arduino Uno, the feeder is connected to a platform that uses load cells to detect the pet’s weight. The weight data is then used to identify which animal is looking for food. Once the pet is identified, the correct food bowl opens. It seems this prototype only has one food chamber to keep unauthorized pets from eating the special food, but the basic idea should be extensible to two or more chambers. While some existing solutions read the pet’s microchip or NFC collars to determine who’s at the feeder, [tomasdiazwahl] decided against these given the fickleness of trying to reliably get a reader at the correct position relative to the pet. As long as you don’t have multiple pets with the same weight, it should work just fine.

This project has a nice mix of woodworking, 3D printing, and electronics showing what can be accomplished when you aren’t afraid to mix techniques. We also really appreciate that [Tomasdiazwahl] spent the extra time to include a testing procedure and safety mechanism into the project. Designing a device to improve your pet’s health shouldn’t come with a safety risk!

This isn’t the first cat feeder we’ve covered that uses weight to tell the difference between the pets, and if you want a simpler project to start with, check out this Simple Auger Pet Feeder.

A machine that holds a combination padlock and turns its dial, with two padlocks next to it

Robot Opens Master Combination Locks In Less Than A Minute

September 18, 2022 by Robin Kearey 28 Comments

A common trope in bank heist B-movies is someone effortlessly bypassing a safe’s combination lock. Typically, the hero or villain will turn the dial while listening to the internal machinery, then deduce the combination based on sounds made by the lock. In real life, high-quality combination locks are not vulnerable to such simple attacks, but cheap ones can often be bypassed with a minimum of effort. Some are so simple that this process can even be automated, as [Mew463] has shown by building a machine that can open a Master combination lock in less than a minute.

The operating principle is based on research by Samy Kamkar from a couple of years ago. For certain types of Master locks, the combination can be found by applying a small amount of pressure on the shackle and searching for locations on the dial where its movement becomes heavier. A simple algorithm can then be used to completely determine the first and third numbers, and find a list of just eight candidates for the second number.

[Mew463]’s machine automates this process by turning the dial with a stepper motor and pulling on the shackle using a servo and a rack-and-pinion system. A magnetic encoder is mounted on the stepper motor to determine when the motor stalls, while the servo has its internal position encoder brought out as a means of detecting how far the shackle has moved. All of this is controlled by an Arduino Nano mounted on a custom PCB together with a TMC2208 stepper driver.

The machine does its job smoothly and quickly, as you can see in the (silent) video embedded below. All design files are available on the project’s GitHub page, so if you’ve got a drawer full of these locks without combinations, here’s your chance to make them sort-of-useful again. After all, these locks’ vulnerabilities have a long history, and we’ve even seen automated crackers before.

Continue reading “Robot Opens Master Combination Locks In Less Than A Minute” →

TickTag, a tiny GPS logger with 3d printed case, LiPo battery and a 1 Euro coin for size reference

Tiny GPS Logger For The Internet Of Animals

September 18, 2022 by Abe Connelly 35 Comments

[Trichl] has created a tiny GPS logger, called ‘TickTag’, designed as an inexpensive location tracking option for animal studies. The low cost, tiny form factor, and large power density of the LiPo battery give it the ability to track large populations of small animals, including dogs and bats.

The TickTag is capable of getting 10,000 GPS fixes from its 30 mAh cell. Each unit is equipped with an L70B-M39 GPS module controlled by an Atmel ATtiny1626 microcontroller and sports a tiny AXE610124 10-pin connection header for programming and communication. GPS data is stored on a 128 kB EEPROM chip with each GPS location fix using 25 bits for latitude, 26 bits for longitude, and 29 bits for a timestamp. Add it all up and you get 10 bytes per GPS data point (25+26+29=80), giving the 10k GPS fix upper bound.

To record higher quality data and extend battery life, the TickTag can be programmed to record GPS location data using variable frequency intervals or when geofencing bounds have been crossed.

Continue reading “Tiny GPS Logger For The Internet Of Animals” →

TRS-80 Model II Lives Again

September 17, 2022 by Al Williams 15 Comments

A lot of people had a Radio Shack TRS-80 Model I. This was a “home computer” built into a keyboard that needed an external monitor or TV set. Later, Radio Shack would update the computer to a model III which was a popular “all in one” option with a monitor and even space for — gasp — floppy disks. But the Model II was not nearly as common. The reason? It was aimed at businesses and priced accordingly. [Adrian] got a Model II that was in terrible shape and has been bringing it back to life. You can see the video of how he’s done with it, below.

The Model II was similar to the older “Trash 80” which had been used — to Radio Shack’s surprise — quite often by businesses. But it had more sophisticated features including a 4MHz CPU — blistering speed for those days. It also had an 80×25 text display and a 500K 8-inch floppy drive. There were also serial and printer ports standard.

There were a few interesting features. The floppy drive’s spindle ran on AC power and if the computer was on, the disk was spinning. In addition, there was bank switching so you could go beyond 64K and also you didn’t have to share your running memory with the video display. In theory, the machine could go beyond 64K since half the memory was bank switchable. In practice, the early models didn’t have enough expansion space to handle more than 64K physically.

Continue reading “TRS-80 Model II Lives Again” →

The CPSC Says Plug To Socket, Not Plug To Plug, Please

September 17, 2022 by Jenny List 102 Comments

When the power goes out, it goes without saying that all the lights and sockets in a house stop working. Savvy rural homeowners stock up with candles, batteries, LED lights, and inverters. More foolhardy folks simply hook up their home electrical system to a generator using a mains lead with a plug on one end between the generator and a wall socket. This should be so obviously dangerous as to be unnecessary, but it’s become widespread enough that the US Consumer Product Safety Commission has issued a warning about the practice. In particular, they’re concerned that there’s not even a need to wire up a lead, as they’re readily available on Amazon.

The dangers they cite include electrocution, fire hazard from circumventing the house electrical protection measures, and even carbon monoxide poisoning because the leads are so short that the generator has to be next to the socket. Hackaday readers won’t need telling about these hazards, even if in a very few and very special cases we’ve seen people from our community doing it. Perhaps there’s a flaw in the way we wire our homes, and we should provide a means to decouple our low-power circuits when there’s a power cut.

It’s likely that over the coming decades the growth of in-home battery storage units following the likes of the Tesla Powerwall will make our homes more resilient to power cuts, and anyone tempted to use a plug-to-plug lead will instead not notice as their house switches to stored or solar power. Meanwhile, some of us have our own ways of dealing with power outages.

Plug image: Evan-Amos, Public domain.

DIY Haptic-Enabled VR Gun Hits All The Targets

September 17, 2022 by Donald Papp 3 Comments

This VR Haptic Gun by [Robert Enriquez] is the result of hacking together different off-the-shelf products and tying it all together with an ESP32 development board. The result? A gun frame that integrates a VR controller (meaning it can be tracked and used in VR) and provides mild force feedback thanks to a motor that moves with each shot.

But that’s not all! Using the WiFi capabilities of the ESP32 board, the gun also responds to signals sent by a piece of software intended to drive commercial haptics hardware. That software hooks into the VR game and sends signals over the network telling the gun what’s happening, and [Robert]’s firmware acts on those signals. In short, every time [Robert] fires the gun in VR, the one in his hand recoils in synchronization with the game events. The effect is mild, but when it comes to tactile feedback, a little can go a long way.

The fact that this kind of experimentation is easily and affordably within the reach of hobbyists is wonderful, and VR certainly has plenty of room for amateurs to break new ground, as we’ve seen with projects like low-cost haptic VR gloves.

[Robert] walks through every phase of his gun’s design, explaining how he made various square pegs fit into round holes, and provides links to parts and resources in the project’s GitHub repository. There’s a video tour embedded below the page break, but if you want to jump straight to a demonstration in Valve’s Half-Life: Alyx, here’s a link to test firing at 10:19 in.

There are a number of improvements waiting to be done, but [Robert] definitely understands the value of getting something working, even if it’s a bit rough. After all, nothing fills out a to-do list or surfaces hidden problems like a prototype. Watch everything in detail in the video tour, embedded below.

Continue reading “DIY Haptic-Enabled VR Gun Hits All The Targets” →