It’s not every day that we see someone trying something new with robot locomotion, but [kong]’s robot Rollyboi was made to do exactly that by mixing up the usual robot-wheel-motor layout. Instead of the robot using motors to drive wheels, Rollyboi is itself the wheel, and uses multiple simple arms (legs?) attached to hobby servo motors to propel itself. The idea is that the arms swivel out one at a time to roll the robot along as needed.
It’s a novel idea, but how well does it work in practice? The first version was blind and mechanically unstable, with no idea which way was up and therefore no way to effectively control which arm needed to be extended, but was nevertheless able to roll along. The next version implemented a simple control system: buttons installed along the outside rim let the robot know how it is moving and which arm to extend next. With two sets of arms (one on each side) the robot becomes capable of executing simple turns by extending one arm more than the other.
In the end, Rollyboi could move but still lacks a means to perceive and navigate its environment. This is made more challenging by the fact that the robot’s body (and therefore any sensors mounted to it) would be in constant motion as the robot moves. Still, it’s interesting to see how far the idea went using only simple hardware, and its motion gives off a certain radial solenoid engine vibe. You can watch a brief video below.
Companion robots are a breed that, heretofore, we’ve primarily seen in cinema. Free from the limits of real-world technology, they manage to be charismatic, cute, and capable in ways that endear them to audiences the world over. Jorvon Moss and Alex Glow decided that this charming technology shouldn’t just live on the silver screen, and have been developing their own companion bots to explore this field. Lucky for us, they came down to Hackaday Superconference to tell us all about it!
The duo use a variety of techniques to build their ‘bots, infusing them with plenty of personality along the way. Jorvon favors the Arduino as the basis of his builds, while Alex has experimented with the Google AIY Vision Kit, BBC Micro:bit, as well as other platforms. Through clever design and careful planning, the two common maker techniques to create their unique builds. Using standard servos, 3D printed body parts, and plenty of LEDs, it’s all stuff that’s readily accessible to the home gamer.
[Alex]’s companion bot, Archimedes, has been through many upgrades to improve functionality. Plus, he’s got a cute hat!Having built many robots, the different companions have a variety of capabilities in the manner they interact. Alex’s robot owl, Archimedes, uses machine vision to find people, and tries to figure out if they’re happy or sad. If they’re excited enough, it will give the person a small gift. Archimedes mounts on a special harness Alex built out of armature wire, allowing the avian to perch on her shoulder when out and about. Similarly, Jorvon’s Dexter lurks on his back, modeled after a monkey. Featuring an LED matrix for emotive facial expressions, and a touch sensor for high fives, Dexter packs plenty of character into his 3D printed chassis.
Alex and Jorvon also talk about some of the pitfalls and challenges they’ve faced through the development of their respective companion bots. Jorvon defines a companion robot as “any robot that you can take with you, on any type of adventure”. Being out in the real world and getting knocked around means breakages are common, with both of the duo picking up handfuls of smashed plastic and bundles of wires at times. Thankfully, with 3D printing being the tool of the trade, it’s easy to iteratively design new components to better withstand the rough and tumble of daily life out and about. This also feeds into the rest of the design process, with Jorvon giving the example of Dexter’s last minute LED upgrades that were built and fitted while at Supercon.
Develop on companion bots is never really finished. Future work involves integrating Chirp.io data-over-sound communications to allow the bots to talk. There’s been some headaches on the software side, but we look forward to seeing these ‘bots chatting away in their own droid language. While artificial intelligence doesn’t yet have homebrew companion bots matching the wisecracking droids seen in movies, designing lifelike bodies for our digital creations is a big step in that direction. With people like Alex and Jolyon on the case, we’re sure it won’t be long before we’re all walking around with digital pals on our shoulders — and it promises to be fun!
Building your own self-balancing robot is a rite of passage for anyone getting into the field of robotics. Master of robots, [James Bruton] has been there, done that, and collected a few T-shirts. Now he’s building a large Sonic the Hedgehog self balancing robot that can bend at the knees and hip, allowing it to lean while turning and handle uneven terrain. Check out the first video embedded after the break.
Standing about 1 m tall, the robot is inspired by Boston Dynamic’s box handling bot, Handle. It’s “skeleton” consists of 20×20 aluminium extrusions, bolted together using a bunch of 3D printed fittings in the signature blue and red of Sonic. The wheels and tyres are also 3D printed, and driven by brushless motor via a toothed belt. The knee/hip mechanism is actuated using a ball screw, also driven by a brushless motor.
[James] intends to implement an active shock absorption system into the leg mechanism, using the same technique he tried on his OpenDog robot. It works by bolting a load cell onto one of the leg extrusion to sense when it flexes under load, and then actuating the knee mechanism to absorb the force. His first version of the system on OpenDog used PWM signals to send the load cell data to the main controller, but the motors on the legs induced enough noise in the signal wires to make it unusable. He has since started experimenting with the CAN bus protocol, which was specifically designed to work reliably in noisy systems like modern automobiles. If he gets it working on the two legs of this Sonic robot, he plans to also implement it on the quadruped OpenDog.
We’ve all seen the two-color sequin fabrics you can “draw” on by dragging your finger over so the pieces flip to the other color. It’s fun stuff to play with, and very popular with the kids right now, but if you asked us if the material had any practical application we’d have said no. But that was before we saw this clever clock created by [Ekaggrat Singh Kalsi] that he calls Sequino.
Since a clock (at least one that only shows hours and minutes) doesn’t need to refresh very quickly, [Ekaggrat] thought that the sequin material could work as a display. Of course the tricky part is figuring out how to actually draw on it reliably. It can’t be done from the back, and since the sequins are plastic, you can’t use a magnet. The only way to do it is with a robotic “finger” and some very slick kinematics.
The most obvious feature of the Sequino is the belt drive that goes the length of its cylindrical shape. When the two motors connected to the belt are turning in the same direction, the pointer is moved left or right. But when the motors turn in opposite directions, the tension on the belt forces the pointer to extend and contact the sequins. It’s like an H-bot , but with the shortest ever Y axis. The front bar is moved up and down with rotating rings inside of the device. It will probably make a lot more sense once you watch the video of it in operation after the break.
Fair warning for the squeamish: some versions of [Will Cogley]’s animatronic heart are realistic enough that you might not want to watch the video below. That’d be a shame though, because he really put a lot of effort into the build, and the results have a lot to teach about mimicking the movements of living things.
As for why one would need an animatronic heart, we’re not sure. [Will] mentions no specific use case for it, although we can think of a few. With the Day of Compulsory Romance fast approaching, the fabric-wrapped version would make a great gift for the one who stole your heart, while the silicone-enrobed one could be used as a movie prop or an awesome prank. Whatever the reason, [Will]’s build is a case study in incremental development. He started with a design using a single continuous-rotation servo, which powered four 3D-printed paddles from a common crank. The four paddles somewhat mimicked the movements of the four chambers of the heart, but the effect wasn’t quite convincing. The next design used two servos and complex parallelogram linkages to expand each side of the heart in turn. It was closer, but still not quite right.
After carefully watching footage of a beating heart, [Will] decided that his mechanism needed to imitate the rapid systolic contraction and slow diastolic expansion characteristic of a real heart. To achieve this, his final design has three servos plus an Arduino for motion control. Slipped into a detailed silicone jacket, the look is very realistic. Check out the video below if you dare.
We’ve seen plenty of animatronic body parts before, from eyes to hands to entire faces. This might be the first time we’ve seen an animatronic version of an internal organ, though.
Soft robots have a lot of advantages, but as [Arnav] points out on his website, it’s pretty hard to get started in the same way as one might with another type of project. You can’t necessarily go on Amazon and order a ten pack of soft robot actuators in the way you can Arduinos.
The project started by imitating other projects. First he copied the universities who have done work in this arena by casting soft silicone actuators. He notes the same things that they did, that they’re difficult to produce and prone to punctures. Next he tried painting foam with silicone, which worked, but it was still prone to punctures, and there was a consensus that it was creepy. He finally had a breakthrough playing with origami shapes. After some iteration he was able to print them reliably with an Ultimaker.
Finally to get it into the “easy to hack together on a weekend” range he was looking for: he designed it to be VEX compatible. You can see them moving in the video after the break.
Mowing the lawn is one of those repetitive tasks most of us really wish we had a robot for. [Kenny Trussell] mowing needs are a bit more strenuous than most backyards, so he hacked a ride-on mower to handle multi-acre fields all on it’s own.
The mower started out life as a standard zero turn ride on lawn mower. It’s brains consist of a PixHawk board running Ardurover, an Ardupilot derivative for ground vehicles. Navigation is provided by a RTK GPS module that gets error corrections from a fixed base station via an Adafruit LoRa feather board, to achieve centimetre level accuracy. To control the mower, [Kenny] replaced the pneumatic shocks that centred the control levers with linear actuators.
So far [Kenny] has been using the mower to cut large 5-18 acre fields, which would be a very time-consuming job for a human operator. A relay was added to the existing safety circuit that only allows the mower to function when there is weight on the seat. This relay is wired directly to the RC receiver and is controlled from the hand-held RC transmitter. It will also stop the mower if it loses signal to the transmitter. To set up mowing missions, [Kenny] uses the Ardupilot Mission Planner for which he wrote a custom command line utility to create a concentric route for the mower to follow to completely cover a defined area. He has made a whole series of videos on the process, which is very handy for anyone wanting to do the same. We’re looking forward to a new video with all the latest updates.
This mower has been going strong for two years, but in terms of hours logged it’s got nothing on this veteran robotic mower that’s been at it for more than two decades and still runs off an Intel 386 processor.
It’s a novel idea, but how well does it work in practice? The first version was blind and mechanically unstable, with no idea which way was up and therefore no way to effectively control which arm needed to be extended, but was nevertheless able to roll along. The next version implemented a simple control system: buttons installed along the outside rim let the robot know how it is moving and which arm to extend next. With two sets of arms (one on each side) the robot becomes capable of executing simple turns by extending one arm more than the other.
