Robots Invade Your Personal Space

September 5, 2018 by Brian McEvoy 13 Comments

If you have ever had to complete a task such as building a LEGO model over a remote connection, you will know that the challenges are like an absurd grade school group project. The person giving directions often has trouble describing what they are thinking, and the person doing the work has trouble interpreting what the instructor wants. “Turn the blue block over. No, only half way. Go back. Now turn it. No, the other way. NO! Not clockwise, downward. That’s Upward! Geez. Are you even listening‽” Good times.

While you may not be in this situation every day, the Keio University of Japan has an intuitive way to give instructors a way to physically interact with an instructee through a Moore/Swayze experience. The instructor has a camera in typical pirate parrot placement over the shoulder. Two arms are controlled by the instructor who can see through stereoscopic cameras to have a first-person view from across the globe. This natural way to interact with the user’s environment allows muscle memory to pass from the instructor to the wearer.

For some of the other styles of telepresence, see this deep-sea bot and a cylindrical screen that looks like someone is beaming up directly from the holodeck.

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A Servo Powered Robotic Arm, But Like You’ve Never Seen Before

September 4, 2018 by Ben James 26 Comments

We’ve written about a lot of DIY robotic arms. Some of them are high-performance, some are inexpensive, and some are just uniquely fun. This one certainly falls into the last category; whilst watching an episode of Black Mirror, [Gear Down For What] was struck by inspiration for a thin robotic limb. After some iterations he has a final prototype, and it’s quite something to see in action.

To make a robotic arm as slender as possible, the actuators can’t be mounted on the arm itself but must instead drive the arm remotely. There are a number of ways of doing this, and though [Gear Down For What] considered using pneumatics or hydraulics, he opted to keep it simple with RC servos which produced a nifty solution that we really like.

The arm is made out of a series of 3D printed ball joints, allowing rotation in any direction. The tricky bit is transferring the force from the servos to each joint. Initially bare fishing line was considered, but this made the remote joints difficult to control when lower joints were moving. The solution was to use the fishing line inside of tubing, similar to the way that bike brakes operate. This allows the force to be carried to the appropriate joint regardless of lower movement. Each joint needs an x and y tension to allow it to rotate in any direction, which means an army of sixteen servos is needed to operate the eight segment arm.

Robotic arms are always fun to build and we’ve seen some pretty neat uses for them, such as mapping magnetic fields in 3D, or teaching sign language.

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Real Or Fake? Robot Uses AI To Find Waldo

August 30, 2018 by Adam Fabio 26 Comments

The last few weeks have seen a number of tech sites reporting on a robot which can find and point out Waldo in those “Where’s Waldo” books. Designed and built by Redpepper, an ad agency. The robot arm is a UARM Metal, with a Raspberry Pi controlling the show.

A Logitech c525 webcam captures images, which are processed by the Pi with OpenCV, then sent to Google’s cloud-based AutoML Vision service. AutoML is trained with numerous images of Waldo, which are used to attempt a pattern match. If a pattern is found, the coordinates are fed to PYUARM, and the UARM will literally point Waldo out.

While this is a totally plausible project, we have to admit a few things caught our jaundiced eye. The Logitech c525 has a field of view (FOV) of 69°. While we don’t have dimensions of the UARM Metal, it looks like the camera is less than a foot in the air. Amazon states that “Where’s Waldo Delux Edition” is 10″ x 0.2″ x 12.5″ inches. That means the open book will be 10″ x 25″. The robot is going to have a hard time imaging a surface that large in a single image. What’s more, the c525 is a 720p camera, so there isn’t a whole lot of pixel density to pattern match. Finally, there’s the rubber hand the robot uses to point out Waldo. Wouldn’t that hand block at least some of the camera’s view to the left?

We’re not going to jump out and call this one fake just yet — it is entirely possible that the robot took a mosaic of images and used that to pattern match. Redpepper may have used a bit of movie magic to make the process more interesting. What do you think? Let us know down in the comments!

Soft Hydraulic Muscles Lift Weights As A Team

August 26, 2018 by Steven Dufresne 17 Comments

Working with hydraulics usually means having a fluid tank and valves. [consciousflesh] does away with both those for his DIY hydraulic artificial muscles. Instead, he uses a pair of muscles, both preloaded with fluid. To contract one, he pumps the fluid into the other, expanding that one, and vice versa. A bidirectional gear pump moves the fluid while also acting as a valve. And flexible materials replace heavy metal cylinders.

As we said, this is a DIY project. He made the muscles by surrounding silicone tubes with aramid fiber sleeves, giving added strength. The blocks at either end are also custom-made. The gear pump is one he purchased and made substantial modifications to, including removing the tank and fixing a brushless DC motor to one end. The final custom piece was a controller board for the motor. A Gerber file, schematic, and technical drawings, along with further details are all on his Hackaday.io page. Meanwhile, check out the load test in the video below as the muscles lift and lower 5 kg (11 lbs) each.

A search of Hackaday shows hydraulic artificial muscles may be rare, so perhaps this will be the first of many. For example, how about replicating how human arm muscles work together, one contracting while the other expands? We’ve seen that done already using pneumatics with [James Hobson’s] exoskeleton arms. Perhaps someone should do it with these pairs of flexible hydraulic muscles?

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A Peek At The Mesmerizing Action Of A Cycloidal Drive

August 24, 2018 by Donald Papp 34 Comments

Cycloidal drives are fascinating pieces of hardware, and we’ve seen them showing up in part due to their suitability for 3D printing. The open source robot arm makers [Haddington Dynamics] are among those playing with a cycloidal drive concept, and tucked away in their August 2018 newsletter was a link they shared to a short but mesmerizing video of a prototype, which we’ve embedded below.

A 10:1 Cycloidal Drive [Source: Wikipedia, image public domain]

A cycloidal drive has some similarities to both planetary gearing and strain-wave gears. In the image shown, the green shaft is the input and its rotation causes an eccentric motion in the yellow cycloidal disk. The cycloidal disk is geared to a stationary outer ring, represented in the animation by the outer ring of grey segments. Its motion is transferred to the purple output shaft via rollers or pins that interface to the holes in the disk. Like planetary gearing, the output shaft rotates in the opposite direction to the input shaft. Because the individual parts are well-suited to 3D printing, this opens the door to easily prototyping custom designs and gearing ratios.

[Haddington Dynamics] are the folks responsible for the open source robot arm Dexter (which will be competing in the Hackaday Prize finals this year), and their interest in a cycloidal drive design sounds extremely forward-thinking. Their prototype consists of 3D printed parts plus some added hardware, but the real magic is in the manufacturing concept of the design. The idea is for the whole assembly to be 3D printed, stopping the printer at five different times to insert hardware. With a robot working in tandem with the printer, coordinating the print pauses with automated insertion of the appropriate hardware, the result will be a finished transmission unit right off the print bed. It’s a lofty goal, and really interesting advancement for small-scale fabrication.

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An Achievable Underwater Camera

August 18, 2018 by Jenny List 11 Comments

We are surrounded by sensors for all forms of environmental measurement, and a casual browse through an electronics catalogue can see an experimenter tooled up with the whole array for a relatively small outlay. When the environment in question is not the still air of your bench but the turbulence, sand, grit, and mud of a sea floor, that pile of sensors becomes rather useless. [Ellie T] has been addressing this problem as part of the study of hypoxia in marine life, and part of her solution is to create an underwater camera by encasing a Raspberry Pi Zero W and camera in a sturdy enclosure made from PVC pipe. She’s called the project LoBSTAS, which stands for Low-cost Benthic Sensing Trap-Attached System.

The housing is simple enough, the PVC has a transparent acrylic disk mounted in a pipe coupler at one end, with the seal being provided at the other by an expansion plug. A neopixel ring is mounted in the clear end, with the Pi camera mounted in its centre. Meanwhile the Pi itself occupies the body of the unit, with power coming from a USB battery bank. The camera isn’t the only sensor on this build though, and Atlas Scientific oxygen sensor completes the package and is mounted in a hole drilled in the expansion plug and sealed with silicone sealant.

Underwater cameras seem to have featured more in the earlier years of Hackaday’s existence, but that’s not to say matters underwater haven’t been on the agenda. The 2017 Hackaday Prize was carried off by the Open Source Underwater Glider.

DARPA Goes Underground For Next Challenge

August 16, 2018 by Roger Cheng 16 Comments

We all love reading about creative problem-solving work done by competitors in past DARPA robotic challenges. Some of us even have ambition to join the fray and compete first-hand instead of just reading about them after the fact. If this describes you, step on up to the DARPA Subterranean Challenge.

Following up on past challenges to build autonomous vehicles and humanoid robots, DARPA now wants to focus collective brainpower solving problems encountered by robots working underground. There will be two competition tracks: the Systems Track is what we’ve come to expect, where teams build both the hardware and software of robots tackling the competition course. But there will also be a Virtual Track, opening up the challenge to those without resources to build big expensive physical robots. Competitors on the virtual track will run their competition course in the Gazebo robot simulation environment. This is similar to the NASA Space Robotics Challenge, where algorithms competed to run a virtual robot through tasks in a simulated Mars base. The virtual environment makes the competition accessible for people without machine shops or big budgets. The winner of NASA SRC was, in fact, a one-person team.

Back on the topic of the upcoming DARPA challenge: each track will involve three sub-domains. Each of these have civilian applications in exploration, infrastructure maintenance, and disaster relief as well as the obvious military applications.

Man-made tunnel systems
Urban underground
Natural cave networks

There will be a preliminary circuit competition for each, spaced roughly six months apart, to help teams get warmed up one environment at a time. But for the final event in Fall of 2021, the challenge course will integrate all three types.

More details will be released on Competitor’s Day, taking place September 27th 2018. Registration for the event just opened on August 15th. Best of luck to all the teams! And just like we did for past challenges, we will excitedly follow progress. (And have a good-natured laugh at fails.)