Lane Keeping RC Car Uses OpenCV

October 16, 2019 by Lewin Day 1 Comment

Automakers continue to promise that fully autonomous cars are around the corner, but we’re still not quite there yet. However, there are a broad range of driver assist technologies that have come to market in recent years, with lane keeping assist being one of them. [raja_961] decided to implement this technology on an RC car, using a Raspberry Pi.

A regular off-the-shelf RC car is used as the base of the platform, outfitted with two drive motors and a third motor used for the steering. Unfortunately, the car can only turn either full-left or full-right only, limiting the finesse of the steering. Despite this, the work continued. A Raspberry Pi 3 was fitted out with a motor controller and camera, and hooked up to the chassis. With everything laced up, a Python script is used along with OpenCV to run the lane-keeping algorithm.

[raja_961] does a great job of explaining the lane keeping methodology. Rather than simply invoking a library and calling it good, instead the Instructable breaks down each stage of how the algorithm works. Incoming images are converted to the HSL color system, before a series of operations is used to pick out the apparent slope of the lane lines. This is then used with a PID algorithm to guide the steering of the car.

It’s a comprehensive explanation of a basic lane-keeping algorithm, and a great place to start if you’re interested in learning about the technology. There’s plenty going on in the world of self-driving RC cars, you just need to know where to look! Video after the break.

Continue reading “Lane Keeping RC Car Uses OpenCV” →

Repurposing A Toy Computer From The 1990s

October 14, 2019 by Tom Nardi 23 Comments

Our more youthful readers are fairly likely to have owned some incarnation of a VTech educational computer. From the mid-1980s and right up to the present day, VTech has been producing vaguely laptop shaped gadgets aimed at teaching everything from basic reading skills all the way up to world history. Hallmarks of these devices include a miserable monochrome LCD, and unpleasant membrane keyboard, and as [HotKey] found, occasionally a proper Z80 processor.

It started, as such things often do, with eBay. [HotKey] found that the second hand market is flooded with these decades-old educational gadgets, often selling for just a few bucks. As it turns out, children of the smartphone and tablet era don’t seem terribly interested in a “laptop” from 1991. At any rate, he ordered about a dozen different models and started tearing into them to see what made them tick.

He found that the VTech machines of around 20+ years old were using the Z80 processor, and what’s more, they shared a fairly standardized external cartridge interface for adding additional software or saving data. Upon attempting to dump some data from the cartridge port, [HotKey] discovered that it was actually connected to the computer’s main bus. He realized that with a custom designed cartridge, it should be able to take over the system and have it run his own code.

After more than a year of tinkering and talking to other hackers in the Z80 scene, [HotKey] has made some impressive headway. He’s not only created a custom cartridge that lets him load new code and connect to external devices, but he’s also added support for a few VTech machines to z88dk so that others can start writing their own C code for these machines. So far he’s created some very promising proof of concept programs such as a MIDI controller and serial terminal, but ultimately he hopes to create a DOS or CP/M like operating system that will elevate these vintage machines from simple toys to legitimate multi-purpose computers.

We’ve seen VTech hardware hacked in the past, but it’s generally been focused on the company’s more recent hardware such as the Linux-powered InnoTab. It will be interesting to see if these educational toys can fulfill some hacker’s dreams of having a cheap and portable box for Z80 tinkering.

This Hurricane Uses A Novel Technique

October 5, 2019 by Jenny List 16 Comments

You’ve probably heard of the brave pilots, the so-called ‘few’, that took to the air in their Supermarine Spitfires and saved the day during the Battle of Britain. It’s a story that contains a lot of truth, but as is so often the case, it masks a story with a bit more complexity. Those pilots did scramble across the airfields of Southern England back in the summer of 1940, but more of them went into battle behind the controls of a Hawker Hurricane than its more glamorous stablemate.

The Hurricane might have been eclipsed by the Spitfire in the public’s eye, but not for [Marius Taciuc], who’s made a fully-functional RC model of one. Normally that wouldn’t be worthy of our attention, but in this case he’s employed a rather fascinating construction technique. He’s recreated the doped-fabric skin of the original by 3D-printing the frame of the aircraft and covering it in heat-shrink film, making this a very rare bird indeed.

The video below takes us through the steps including the development of the frame in a CAD package based on a tracing of a 2D aircraft picture, fitting the film, and finally attempts at flight that are unfortunately foiled by inappropriate wheel choice. But the short flight and crash does demonstrate that this construction method is durable, which leads on to our interest in it. While it evidently makes a functional aircraft, there are other applications that could benefit from such a lightweight and strong combination of materials.

[Marius] actually created a model of the somewhat more photogenic Spitfire using a similar technique, though as far as we can tell, that one has remained grounded. Incidentally, these pages have been previously graced by Hurricanes of the non-PLA variety. Continue reading “This Hurricane Uses A Novel Technique” →

Meccano Max Gets Hacked

September 20, 2019 by Lewin Day 2 Comments

There are plenty of “smart” toys out in the marketplace, some with more features than others. Nevertheless, most makers desire complete control over a platform, something that’s often lacking in any commercial offering. It was just this desire that motivated [MrDreamBot] to start hacking the Meccano Max.

Meccano Max is a small-statured companion robot, at about 30 centimeters high. Not content with the lack of an API, [MrDreamBot] decided to first experiment with creating an Arduino library to run Max’s hardware. With this completed, work then began on integrating a Hicat Livera devboard into the hardware. This is an embedded Linux system with Arduino compatibility, as well as the ability to stream video and connect over WiFi. Thus far, it’s possible to control Max through a browser, while viewing a live video feed from the ‘bot. It’s also possible to customize the expressions displayed on Max’s face.

Oftentimes, it pays to replace stock hardware rather than try and work with the limitations of the original setup, and this project is no exception. With that said, we’re still hoping someone out there will find a way to get Jibo back online. Look after your robot friends! Video after the break.

Continue reading “Meccano Max Gets Hacked” →

Custom Lego Server Case Looks As Though It Came Straight From A Data Center

September 11, 2019 by Dan Maloney 12 Comments

The picture above appears to show two unremarkable 2U rack servers, of the kind that are probably hosting the page you’re reading right now. Nothing special there – until you look carefully and realize that the rack server case on the left is made entirely from Lego. And what’s more, the server even works.

When it comes to building Lego computers, [Mike Schropp] is the guy to call. We’ve previously featured his Lego gaming computer, a striking case wrapped around what was a quite capable machine by 2016 standards, as well as an earlier case that reminds us a little of a NeXT. His reputation for Lego-clad computers led server maker Silicon Mechanics to commission a case for a trade show, and [Mike] jumped at the challenge.

Making a home-grade machine is one thing, but supporting all the heavy drives, power supplies, and fans needed to make the machine work is something else. He used a combination of traditional Lego pieces along with a fair sampling of parts from the Lego Technics line to pull off the build, which looks nearly perfect. Sadly, the Lego unit sizes make the case slightly taller than 2U, but that’s a small quibble when everything else matches so well, even the colors. And the fact that the server works, obviously important for a trade show demo, is pretty amazing too. The power supplies are even hot-swappable!

Congratulations to [Mike] on yet another outstanding Lego creation.

Lego House: Right Next To Denmark’s Legoland, But Way Cooler

September 9, 2019 by Jenny List 32 Comments

If there is one thing that most Hackaday readers will know about Denmark, it is that it’s the home of the Lego brick. The toy first appeared at the end of the 1940s from the factory of Ole Kirk Christiansen‘s Lego company in Billund, central Denmark, and has remained inseparable from both the town and the country ever since.

When spending a week in Denmark for the BornHack hacker camp it made absolute sense to take a day out to drive up to Billund and visit the famous Legoland theme park. All those childhood dreams of seeing the fabled attraction would be satisfied, making the visit a day to remember.

Your first view of the Lego House, in the centre of Billund.

The Danes at Bornhack however had other ideas. By all means go to Legoland they said, but also take in Lego House. As a Brit I’d never heard of it, so was quickly educated. It seems that while Legoland is a kid’s theme park, Lego House is a far more Lego-brick-focused experience, and in the view of the Danish hackers, much better.

Continue reading “Lego House: Right Next To Denmark’s Legoland, But Way Cooler” →

Race RC Cars From Anywhere On Earth

August 31, 2019 by Lewin Day 9 Comments

Racing games have come a long way over the years. From basic 2D sprite-based titles, they’ve evolved to incorporate advanced engines with highly realistic simulated physics that can even be used to help develop real-world automobiles. For [Surrogate.tv], that still wasn’t quite good enough, so they decided to create something more rooted in reality.

The game is played in a web browser. Players are assigned a car and view the action from a top-down camera.

Their project resulted in a racing game based on controlling real RC cars over the internet, in live races against other human opponents. Starting with a series of Siku 1:43 scale RC cars, the team had to overcome a series of engineering challenges to make this a reality. For one, the original electronics had to be gutted as the team had issues when running many cars at the same time.

Instead, the cars were fitted with ESP8266s running custom firmware. An overhead GoPro is used with special low-latency streaming software to allow players to guide their car to victory. A computer vision system is used for lap timing, and there’s even automatic charging stations to help keep the cars juiced up for hours of play.

The game is free to play online, with the races currently operating on a regular schedule. We look forward to trying our hand at a race or three, and will be interested to see how the latency holds up from various parts of the world.

We’ve seen other remote RC builds before; usually featuring the power of the Raspberry Pi. We’ve also covered useful techniques for low latency video for real-time applications. Video after the break.

Continue reading “Race RC Cars From Anywhere On Earth” →