If ever any sci-fi robot form-factor made more sense than the Droideka of the Star Wars franchise, we’re not sure what it could be. Able to transform from a spheroid that rolls quickly onto the battlefield into a blaster-bristling tripodal walker, the Hollywood battle droid showed a lot of imagination and resulted in a remarkably feasible design. And now that basic design is demonstrated in a spherical quadrupedal robot that can transform from rolling to walking.
Intended as a proof of concept of a hybrid rolling-walking locomotion system, the QRoSS robot from Japan’s Chiba Institute of Technology is capable of some pretty amazing things already. Surrounded by a wire roll cage that’s independent of the robot’s legs, QRoSS is able to roll into position, unfurl its legs, and walk where it needs to go. Four independent legs make it sure-footed over rough terrain, with obvious applications in such fields as urban search and rescue; a hardened version could be tossed into a collapsed building or other dangerous environment and walk around to provide intelligence or render aid. The robot’s self-righting feature would be especially handy for that use case, and as you can see in the video below, it has a powered rolling mode that’s six times faster than its walking speed.
For a similar spherical transforming robot, be sure to check out the MorpHex robot with its hexapod design.
The world has a severe lack of robots, and the shortage of walking robots is untenable. We were promised flying cars and fusion reactors, yet here we are, 15 years into the twenty-first century without even a robotic pet spider.
To solve humanity’s glaring lack of walking robots, [Radomir] designed Tote, a four-legged robot whose chassis is mostly composed of only 9 gram servos. There are twelve servos in total, three on each of its four legs. It’s an extension of his earlier µKubik robot. While the µKubik was powered by Python, the Tote is all Arduinofied, calculating the trajectories of each leg dozens of times a second with an Arduino Pro Mini.
This isn’t the only walking robot kit on hackaday.io; last year, [The Big One] created Stubby the Teaching Hexapod. Even though Stubby featured six legs, it’s still remarkably similar to Tote; 9 gram servos provide all the locomotion, and all the software is running on a relatively small ATMega microcontroller. Both are great introductions to walking robots, and both bots will surely be capable and just rulers of mankind after the robot apocalypse.
Most of the legged robots we see here are of the hexapod variety, and with good reason. Hexapods are very stable and can easily move even if one or more of the legs has been disabled. [Radomir] has taken this a step farther and has become somewhat of an expert on the more technically difficult quadruped robot, building smaller and smaller ones each time. He has been hard at work on his latest four-legged creation called the Pico-Kubik, and this one will fit in the palm of your hand.
The Pico-Kubik runs Micropython on a VoCore board, which allows for it to have a small software footprint to complement its small hardware footprint. It accomplishes the latter primarily through the use of HK-282A Ultra-Micro Servos, an Arduino Pro Mini, and a tiny lithium ion battery. It’s still a work in progress, but the robot can already crawl across the tabletop.
This isn’t [Radomir]’s first time at the tiny quadruped rodeo, either. He has already built the Nano-Kubik and the µKubik, all of which followed the first (aptly-named) Kubik quadruped. Based on the use of SI prefixes, we can only assume the next one will be the hella-Kubik!
We’ve all seen videos of those crazy Boston Dynamics running quadruped robots that can reach up to 28 mph. Those things are amazing and it’s almost impossible to imagine how to even start building one. [Max] loves his robots and wanted to build a quadruped but, being a robot hobbyist, didn’t have the serious cash needed to make an extravagant robot like those of Boston Dynamics. Instead he started bridging the gap by designing a quadruped robot that is a little bit slower and tons cheaper.
[Max] designed all of the mechanical parts himself. After weighing the advantages and disadvantages of different materials, he decided that the frame would be made from 5mm acrylic sheet. The main body of the robot has acrylic ribs that are spaced apart by threaded rods. Twelve RC servos make up all of the joints, 3 in each leg. Notice in this photo how there is one servo that immediately rotates another servo. To support the other side of the rotating servo, [Max] epoxied on a T-nut, stuck in a short length of threaded rod which is then supported in the frame by a ball bearing. Simple and effective! The upper portions of the legs are also made from acrylic sheet and the lower legs are from a cheap camera tripod. Rubber feet ensure a slip resistant stance.
All of the servos are controlled by an Arduino Mega. [Max] is currently writing a sketch that will perform the complex math and determine coordinated servo motions for movements us humans take for granted, like ‘walk forward’. As you can see in the videos, [Max’s] robot won’t be catching the Boston Dynamics’ Cheetah any time soon but he is off to a great start.
Future plans for this project include bluetooth control and integrating the ultrasonic sensor proactively installed in the ‘head’ of the robot. Check out the videos after the break. [Max] is looking for some feedback on his project. We here at HaD think this needs a great name. Let’s hear some suggestions in the comments…
Back at New York MakerFaire 2012, we noticed an amazing little steampunk quadruped robot walking around in the crowd outdoors. The robot was amazingly well executed, and had a unique ability to draw children over with it’s puppy like animations. It turns out this is [Drew’s] Little Walking Robot (AKA Puppy Bot).
Puppy Bot has actually been around for quite a while. He was born from the spare parts [Drew] had left over after competing in Robot Wars and Battlebots. The robots in these competitions were often controlled by Radio Control plane or car transmitters. Most of these systems are sold as packs for an RC car or plane. In addition to the transmitter and receiver, the pack usually included a battery and 3 or 4 servos. Standard RC servos were much too weak for use in battle robots, so they remained in his parts box.
On what [Drew] calls a slow weekend, he started putting the servos together, and ended up with a basic robot that could crawl around the room. After that the robot took on a life of its own. [Drew] improved the battery system, and added a microcontroller to automate the various gaits and animations. He brought the robot along with him to one of his battlebot competitions, and it took home the “Coolest Robot” award – even though it wasn’t actually competing!
This robot doesn’t know if it’s a walker or a tank. It’s the brain-child of [Marc Hamende] who works as a mechanical engineer by day and mad roboticist at night. The best place to find full details is by digging into the long thread he’s been posting to for about six weeks. It will give you a pretty good snapshot of his approach, starting with SolidWorks renderings of the project, and adding in assembled components as he brings the project together.
The mechanism for each foot is fascinating. He milled the white pieces which stack together to encapsulate the motor that runs the treads. These assemblies pivot to bring the metal rod serving as a walking foot in contact with the ground. But they also make it possible to adjust the treads to deal with rough terrain. A Propeller chip drives the device, with an Xbee module to communicate with the controller.
Don’t miss the video after the break. You’ll hear some skidding as it makes turns, but [Marc] plans to add code to adjust motor speed in order to compensate for the inside/outside differential issues. He’s also posted an image album over at Flickr.
Sure, we see hexapods all the time at [HAD], but moving around with four legs can be more tricky kinematics-wise. This Instructable shows you how to make one out of balsa wood.
Although one might not think of balsa to make their robot out of [vexedpheonix] explains that this was chosen because it’s extremely light and easy to work with. Since he was trying to keep costs down, the cheapest servos available were used. These weren’t all that powerful, so the lighter the body the better! According to the included bill of materials, he was able to keep the entire robot build under $100.
According to the article, the hardest part was making four copies of the same leg. We might suggest using a CNC router, but building one would obviously add a huge layer of complication to the project!