Boston Dynamics Stretch Robot Trades Lab Coat For Work Uniform

March 31, 2021 by Roger Cheng 30 Comments

Boston Dynamics has always built robots with agility few others could match. While great for attention-getting demos, from outside the company it hasn’t been clear how they’ll translate acrobatic skills into revenue. Now we’re getting a peek at a plan in an interview with IEEE Spectrum about their new robot Stretch.

Most Boston Dynamics robots have been research projects, too expensive and not designed for mass production. The closest we got to date was Spot, which was offered for sale and picked up a few high profile jobs like inspecting SpaceX test sites. But Spot was still pretty experimental without an explicit application. In contrast, Stretch has a laser-sharp focus made clear by its official product page: this robot will be looking for warehouse jobs. Specifically, Stretch is designed to handle boxes up to 50 lbs (23 kg). Loading and unloading them, to and from pallets, conveyer belts, trucks, or shipping containers. These jobs are repetitive and tedious back-breaking work with a high injury rate, a perfect opportunity for robots.

But warehouse logistics aren’t as tightly structured as factory automation, demanding more adaptability than typical industrial robots can offer. A niche Boston Dynamics learned it can fill after releasing an earlier demo video showing their research robot Atlas moving some boxes around: they started receiving inquiries into how much that would cost. Atlas is not a product, but wheels were set in motion leading to their Handle robot. Learning from what Handle did well (and not well) in a warehouse environment, the designed evolved to today’s Stretch. The ostrich-like Handle prototype is now relegated to further research into wheeled-legged robots and the occasional fun dance video.

The Stretch preproduction prototypes visible in these videos lacks acrobatic flair of its predecessors, but they still have the perception and planning smarts that made those robots possible. Those skills are just being applied to a narrower problem scope. Once production models are on the job, we look forward to reading some work performance reviews.

Continue reading “Boston Dynamics Stretch Robot Trades Lab Coat For Work Uniform” →

Putting Perseverance Rover’s View Into Satellite View Context

March 30, 2021 by Roger Cheng 3 Comments

It’s always fun to look over aerial and satellite maps of places we know, seeing a perspective different from our usual ground level view. We lose that context when it’s a place we don’t know by heart. Such as, say, Mars. So [Matthew Earl] sought to give Perseverance rover’s landing video some context by projecting onto orbital imagery from ESA’s Mars Express. The resulting video (embedded below the break) is a fun watch alongside the technical writeup Reprojecting the Perseverance landing footage onto satellite imagery.

Some telemetry of rover position and orientation were transmitted live during the landing process, with the rest recorded and downloaded later. Surprisingly, none of that information was used for this project, which was based entirely on video pixels. This makes the results even more impressive and the techniques more widely applicable to other projects. The foundational piece is SIFT (Scale Invariant Feature Transform), which is one of many tools in the OpenCV toolbox. SIFT found correlations between Perseverance’s video frames and Mars Express orbital image, feeding into a processing pipeline written in Python for results rendered in Blender.

While many elements of this project sound enticing for applications in robot vision, there are a few challenges touched upon in the “Final Touches” section of the writeup. The falling heatshield interfered with automated tracking, implying this process will need help to properly understand dynamically changing environments. Furthermore, it does not seem to run fast enough for a robot’s real-time needs. But at first glance, these problems are not fundamental. They merely await some motivated people to tackle in the future.

This process bears some superficial similarities to projection mapping, which is a category of projects we’ve featured on these pages. Except everything is reversed (camera instead of video projector, etc.) making the math an entirely different can of worms. But if projection mapping sounds more to your interest, here is a starting point.

[via Dr. Tanya Harrison @TanyaOfMars]

Continue reading “Putting Perseverance Rover’s View Into Satellite View Context” →

Putting Your Time In

March 27, 2021 by Elliot Williams 28 Comments

I was absolutely struck by a hack this week — [Adam Bäckström]’s amazing robot arm built with modified hobby servos. Basically, he’s taken apart and re-built some affordable off-the-shelf servo motors, and like the 6-Million-Dollar Man, he’s rebuilt them better, stronger, faster. OK, and smoother. We have the technology.

The results are undeniably fantastic, and enable the experienced hacker to get champagne robot motion control on a grape-juice budget by employing some heavy control theory, and redundant sensors to overcome geartrain backlash, which is the devil of cheap servos. But this didn’t come out of nowhere. In his writeup, [Adam] starts off with “You could say this project started when I ordered six endless servos in middle school, more than 15 years ago.” And it shows.

Go check out this video of his first version of the modified servos, from a six-axis arm he built in 2009(!). He’s built in analog position sensors in the motors, which lets him control the speed and makes it work better than any other hobby servo arm you’ve ever seen, but there’s still visible backlash in the gears. A mere twelve years later, he’s got magnetic encoders on the output and a fast inner loop compensates for the backlash. The result is that the current arm moves faster and smoother, while retaining accuracy.

Twelve years. I assume that [Adam] has had some other projects on his plate as well, but that’s a long term project by any account. I’m stoked to see his work, not the least because it should help a lot of others who are ready to step up their desktop servo-arm projects. But the real take-home lesson here is that if you’ve got a tough problem that you’re hacking on, you don’t have to get it done this weekend. You don’t have to get it done next weekend either. Keep hammering on it as long as you need, but keep on hammering. When you get it done, the results will be all the better for the long, slow, brewing time. What’s the longest project that you’ve ever worked on?

Skid Steer Robot Chassis Takes A Beating

March 26, 2021 by Lewin Day 5 Comments

[Engineering After Hours] wanted a highly maneuverable robot chassis with a tight turning radius. Skid steering seemed to be the perfect solution, but the available commercial options didn’t take his fancy. Thus, a custom build was the answer – with impressive results.

The build packs two large RC motors, one for each side, with each driving two wheels through a belt drive. This reduces the electronics required to the bare minimum for skid steering. It’s all assembled within a plasma-cut metal chassis which is more than tough enough to take some hard knocks.

One of the primary goals on the build was to eliminate the risk of vibrations and shock damaging the motors and gearboxes. Many off-the-shelf designs couple the wheels directly to gearbox output shafts, potentially damaging the expensive components over time. In this design, a separate bearing assembly is used to take the load from the wheels instead.

It’s a great example of how an engineering-first approach can build a sturdy ‘bot with a minimum of fuss. Outfitted with some fat off-road tyres the performance is impressive, with the ‘bot having no trouble tearing it up in mud, snow, and water.

We’ve seen other great builds from [Engineering After Hours] before, like the active aero RC build. Video after the break.

Continue reading “Skid Steer Robot Chassis Takes A Beating” →

Robot Arm Achieves Amazing Accuracy With Just Servos

March 19, 2021 by Lewin Day 13 Comments

While few of us need robotic arms in our daily life, they’re a popular build with makers. Often, the most accessible builds throw together some RC servos and 3D printed parts, with limited accuracy a consequence of the components chosen. [Adam Bäckström] decided to take such a design and push it to its limits, however, with astounding results.

Part of the “special sauce” that makes this arm so capable is the custom optical encoders installed in the servo motors themselves.

[Adam]’s first robot arm build was a major disappointment, when the servos he had purchased for the build turned out to be terrible at holding an angle. With limited funds, he elected to improve on what he had, learning much about precision control techniques along the way. [Adam] taught himself how to implement industrial strength control loops using hobby hardware, by implementing additional encoders into servos and taking into account velocity and torque in addition to just position. With a magnetic encoder on the servo output shaft and a tiny optical encoder hand-built for inside the motor itself, much higher accuracy is achievable by allowing the control system to compensate for backlash.

The results are stunning, with [Adam]’s robot arm able to move incredibly smoothly throughout its range of motion. Perhaps the best demonstration of this is the pencil demo, where the robot arm delicately threads a pencil lead through the tip of a mechanical pencil without breaking. We’d love to see these techniques implemented more often; we imagine they’d be a great addition to a build like this one. Video after the break.

Continue reading “Robot Arm Achieves Amazing Accuracy With Just Servos” →

DIY B-Movie Robot Is A-OK

March 17, 2021 by Kristina Panos 12 Comments

While we certainly agree that “Devil Girl From Mars” is an attractive movie title, we have yet to see this apparent British B-movie delight for ourselves. If [Cory Collins]’ fantastic build of Chani, the lumbering, terrifying robot that accompanies the vinyl-clad and caped Devil Girl in question is any indication, we bet it’s delightfully bad.

[Cory] was able to faithfully reproduce Chani — lights, lumbering and all — for less than $50. This price tag does not include the vacuum former required to make the domed head, but hey, it’s an investment into future projects.

[Cory] started by dissecting an R/C stunt car from Harbor Freight and stringing the innards up to a 3D-printed walking mechanism that’s been modified to use gear-reduced motors so it walks more slowly. While Chani is stomping around on TPU treads, the LEDs from the R/C car’s headlights shine inside of its dome. Chani’s boxy body is a big paper sculpture that looks spot-on to us when compared to the movie’s trailer.

We love the way that Chani walks — it sort of dips and glides along in a forward-facing Moonwalk fashion. As you can see in the video below, [Cory] totally nailed the robot’s gait, and it’s hilarious to watch Chani’s little coolant hose-looking arms dangle and shake as he makes his slow and menacing way across the table. Stick around for some scary nighttime footage of Chani against a thunderstorm.

Want your robots to move more like movie robots? All you gotta do is use the right tools.

Continue reading “DIY B-Movie Robot Is A-OK” →

Resilient AI Drone Packs It All In Under 250 Grams

March 15, 2021 by Tom Nardi 14 Comments

When it was first announced that limits would be placed on recreational RC aircraft heavier than 250 grams, many assumed the new rules meant an end to home built quadcopters. But manufacturers rose to the challenge, and started developing incredibly small and lightweight versions of their hardware. Today, building and flying ultra-lightweight quadcopters with first person view (FPV) cameras has become a dedicated hobby onto itself.

But as impressive as those featherweight flyers might be, the CogniFly Project is really pushing what we thought was possible in this weight class. Designed as a platform for experimenting with artificially intelligent drones, this open source quadcopter is packing a Raspberry Pi Zero and Google’s AIY Vision Kit so it can perform computationally complex tasks such as image recognition while airborne. In case any of those experiments take an unexpected turn, it’s also been enclosed in a unique flexible frame that makes it exceptionally resilient to crash damage. As you can see in the video after the break, even after flying directly into a wall, the CogniFly can continue on its way as if nothing ever happened.

Continue reading “Resilient AI Drone Packs It All In Under 250 Grams” →