There are plenty of “robot” projects out there that are really just a small remote control platform of some sort. We often like to think of robots of having some sort of autonomy though. [Luca Fagioli] demonstrates a great example of this with his explorer robot that uses Simultaneous Localization and Mapping (SLAM) to navigate its environment.

The robot is a built on a small plastic chassis, with one gear motor per drive wheel. Running the show is an Arduino Uno R4 Wi-Fi, paired with the Sensor Shield 5.0 and an L298N motor driver board. There’s also an HC-SR04 ultrasonic sensor module onboard, mounted atop an SG-90 servo motor so it can be panned around. The ultrasonic sensor determines the range between the robot and surrounding walls, and a map is constructed at the same time as the robot is localizing itself within it. There are also infrared sensors on the bottom of the robot for detecting tape marks on the floor for checkpointing purposes.

Often, SLAM mapping is done with advanced laser rangefinders or time of flight sensors, but there are many ways to go about it as this project demonstrates. We’ve even seen it done in a distributed manner with coordinated drones combining their efforts. Overall, it’s a highly useful technique for robot navigation and wayfinding.

While Hackaday doesn’t maintain a crime blotter, we couldn’t help but start this week’s post off with a bit of civil disobedience — a retired professor from the University of Pennsylvania was arrested earlier this week for standing in front of a delivery robot.

Granted, she was standing there for long enough that the police were eventually called, but still. Previous reporting indicates that Carolyn Marvin has a history of blocking delivery robots as a form of protest, but this is the first time law enforcement got involved. We’re not lawyers here at Hackaday, so we can’t say for sure whether or not blocking the progress of a robot engaged in commercial operation actually violates any laws. But we do know that refusing a lawful request from a police officer will get you in trouble, and that seems to be what Marvin was actually charged with when she refused to move.

From a robot stopped in its tracks to one that keeps on trucking, NASA is reporting that the odometer on the Perseverance Mars rover recently ticked over to 28.10 miles (45.22 kilometers). That might not seem like a lot, but it officially makes it the most traveled rover in the solar system, breaking the record set by Opportunity at 28.06 miles (45.16 km). One might expect that the Curiosity rover would hold the distance record as it had been rolling around on the surface for more than a decade before Perseverance dropped into the neighborhood, but the different scientific missions of the two nearly identical rovers have taken them on very different courses.

On the subject of navigation, MapQuest recently announced the availability of the “Surveillance Layer” in their smartphone application. When enabled, it shows the location of known license plate readers and cameras on the map, allowing the user to plan their route accordingly. A note in the application’s user interface mentions that they’re pulling at least some of this data from OpenStreetMap, though it’s not clear currently if other sources such as DeFlock are being used.

Finally, we have an update on the Christie’s auction for the carrier pigeon data packet sent back in 2001 by Norway’s Bergen Linux User Group. The auction house thought the framed datagram might fetch as much as $3,000 USD, but when the hammer finally went down earlier this week the winning bid was a staggering $20,480. Given all the weird gadgets we’ve picked up on a whim, we’re not in a position to lecture anyone else about how they spend their money…but damn.

See something interesting that you think would be a good fit for our weekly Links column? Drop us a line, we’d love to hear about it.

If you would like an AI “personal agent” but don’t want your data on some opaque cloud computer, there’s a new option that appears to be somewhat nicer: [rociiu] has talorys, an AI agent that runs in your Cloudflare account. True, it is still on a cloud computer, but it is your account on a cloud computer. It is designed so you can use it on Cloudflare’s free account with reasonable limits, and the code running is all on GitHub, so you can — if you are so inclined — look to see what it is doing. The data, too, is all in your cloud instance.

This seems like a reasonable compromise. Cloudflare provides the hosting, and the software in your virtual computer does all the work. At least, that’s how it is promoted. Honestly, we haven’t combed over the code, but the assertion is “Free-tier friendly… no telemetry.”

We are fairly sure they are using Cloudflare’s AI engines, too, so it would be interesting to see how much of your data they could, in theory, harvest in transit. Of course, your data is still in the cloud, so if you are really worried about privacy, this might not be for you. But since everything is in your account and open, you can at least have more control over what’s there. For example, you can easily download or delete your data. You can even see exactly what prompts it uses.

Are there downsides? Sure. The tool can’t integrate with your calendar, for example. It can’t deal with e-mail, nor can it search the web. It won’t write code for you. This isn’t meant to be a general-purpose chatbot replacement. It is more like an AI tool for keeping a task list.

While Cloudflare does have a free tier, it does have daily limits, and you may hit them. And, of course, if things like this get too popular, they could reduce those limits. The system does let you export your data, though.

It isn’t flawless. We asked it to set up three recurring meetings. It got one right, put the other one in for Sunday instead of Monday (even though the title said Monday), and hit a Cloudflare rate limit and failed to create the third one. We asked it to retry the failed one once, and it didn’t work. So I waited a bit and tried again. It claimed it worked. However, when I looked at the schedule, it wasn’t there.

We then asked it to fix the Sunday schedule and add the one it had missed again. It did add it that time. It also added the Monday meeting, but despite saying it would delete the Sunday one, it didn’t. I manually deleted it.

Installation is easy. You can connect a domain you own to Cloudflare or use the subdomain on pages.dev that they give you, which works fine. You run a single command on your computer. It handles authentication to the server and sets up all the services and data stores.

So essentially it is a to-do, reminder, and note-taking system. However, it does work well when it works. It can remember things and will find things it remembers or in notes very easily. Can you do that with non-AI tools? Of course. Not to mention, any of the “big” chatbots can do all of that and more. But not in your own hosted server account.

Besides, it is interesting that for small uses, Cloudflare offers plenty of free-tier compute resources that might come in handy for other projects. It is nice to have some free cloud-based computers, as we noted in a recent Linux Fu post where we used Oracle’s free servers.

Recently [Ken Shirriff] got handed a mystery IC by [CuriousMarc] who had found said IC in a box of various old chips. Labelled only with a date code of the 47th week of 1985 and a mysterious F1-10-5 alongside a logo that didn’t lead to any hits in the typical IC databases, it was up to [Ken] to figure out what lurks inside this CDIP chip.

As it turns out, it’s actually a pretty interesting IC with an easy to identify die once the ceramic package had been cracked open with a surgical hammer-and-chisel strike.

With the die under a microscope it was identified as a Harris HF10, itself a variant of the National Semiconductor MF10. This is a dual switched capacitor filter, with the modern version being e.g. the TI MF10-N in both PDIP and SOIC, but sadly no CDIP any more. Availability seems scarce, so the MF10 may not be long for this world.

These filter ICs can tune their capacitors to act as a low-, band- or high-pass filter. How this works is explained by [Ken], with switched capacitors replacing the resistors of a typical filter circuit. The main reasons for doing this over just using a resistor include how large resistors can get compared to the relatively small capacitor, not to mention their fixed value versus the adjustable resistance from the switchable capacitor.

The remainder of the circuit is mostly there to enable the switching and overall operation, providing a fascinating glimpse at a chip that would have been incredibly useful in the 1980s, including in synthesizers where this adjustable filter feature was most convenient.