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.

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