As a maker, you probably have a third hand for your soldering station. They come in handy when you need to hold a component, PCB, solder, and soldering iron all at the same time. But an extra hand would be useful for a wide range of other everyday activities. That’s why this team of researchers created a compact robotic third arm called AugLimb.
While robotic augmentations aren’t a new idea, they aren’t often as usable as AugLimb. This robotic arm is lightweight and compact, making it comfortable to wear. It can’t lift much weight, but it is very dexterous thanks to seven degrees of freedom and an extendable gripper. It attaches to the wearer’s bicep and folds up when not in use. When it is time for action, AugLimb unfolds and reaches further than the user’s own arm.
An Arduino Mega board drives AugLimb’s various motors. Those include two shoulder servos, an elbow servo, two wrist servos, a scissor extension motor, and two gripper servos. The scissor extension increases reach by up to 250mm. At this time, a second human operator has to control AugLimb’s movement. But the team hopes to introduce control schemes that let the user operate the robotic limb on their own.
AugLimb is a prototype, but Haoran Xie, a member of the team behind the project, said “We believe that AugLimb will be as popular as smart watches in the near future, as anyone from an elder to a child can comfortably wear it for the whole day.”
Tiny mobile robots are a blast to use. They are fast, fun, and can even be autonomous. However, they all suffer from a similar issue: batteries, which are notorious for running out of charge quickly when the motors are kept spinning for too long. To address this issue, Mike Rigsby came up with a small robot that has a simple “brain” but has the ability to never run out of power.
Rigsby’s robot, named Roamer, starts off on a charging station that is comprised of a large metal plate on the bottom and a small, energized bump rail. The bot contains a spring under its base that contacts the plate, and its front plate contacts the bumper. Therefore, when the two meet, the circuit is completed, and Roamer can determine if it needs to charge.
Roamer’s onboard Arduino Uno is paired with a motor shield that drives both continuous servo motors to both give forward/backward motion and turn side-to-side. There is also a photoresistor on the top of the robot that is used to sense if the room is dark or light. If it is bright enough, the rover will begin its normal pattern of moving in random directions until it needs to top off its batteries, but a dark room causes it to “sleep” until the light returns.
Roamer is a clever demonstration of how simple materials can be implemented to create a robot that can theoretically never run out of power. You can view this timelapse of it below as well as see how the rover was created here on Hackaday.io.
Roboticists often look to nature for inspiration. That makes sense, because animals are very efficient machines, thanks to millions of years of evolution. Even our most sophisticated technology doesn’t come close to matching a common housefly. But we can get closer to mimicking nature at larger scales, as with this robot created by researchers at EPFL that does a great job of swimming like a lamprey.
Lampreys are long, jawless fish that often get mistaken for eels. They swim through the water with a motion similar to a snake slithering across loose sand. To replicate that movement, this robot’s body contains numerous segments joined by servo motors. Each segment also has a force plate on each side. That lets the robot sense the pressure of the water against its body as it swims. An Arduino Mini board monitors the plates through force cells and controls the motors.
This unique setup let the researchers study the ability of some vertebrates to move even with a damaged spinal cord. The “healthy” robot can coordinate the movement of all of its motors. But the robot with the simulated spinal cord injury cannot. The motors past the “injury” can only react to the force plates on their own segments. The team found that the robot was still able to swim efficiently, because the force plates provided enough information to control the motors as needed. This provides valuable information in the field of neuroscience and vertebrate nervous systems.
Almost done with his degree in mechanical engineering, Rose-Hulman Institute of Technology student Josh Eckels had the inspiration to put what he learned to the test by creating an AI-powered robot that plays chess against a human opponent. The system is essentially a giant cube fashioned from a series of aluminum extrusions placed at right angles with a large chess board at its base. At the top is a gantry made with a few metal rods and timing belts that slide the X axis and grabbing mechanism to the correct positions.
Four total stepper motors were used to move the grabber, including one for the X axis, another for the Y axis, a motor that spins a threaded rod to lift the gripper, and a final motor that rotates to open or close it. All of these motors connect to a central Arduino that has a CNC shield on top. This is connected via a USB cable to a Raspberry Pi running the Stockfish chess engine.
Stockfish is a great chess engine that keeps track of the current state of the game and makes moves according to the selected skill level. At the upper ranges, it becomes nearly, if not fully, impossible to beat by a human. The player selects on a screen where they want to position their piece, which then causes the robot to pick it up and place it somewhere else. Afterwards, the engine makes its move.
When we saw Alex Glow’s name in the latest issue of HackSpace magazine, we just had to share their project. HackSpace #45 celebrates the best Raspberry Pi builds of all time, and we remembered spotting Alex’s wearable robotic owl familiar back in the day. For those of you yet to have had the pleasure, meet Archimedes…
An updated model, Archie 2, using Raspberry Pi 3B, ESP32-powered Matrix Voice, and an SG90 micro-servo motor saw the personable owl familiar toughen up – Alex says the 3D-printed case is far more durable – as well as having better voice interaction options using Matrix HAL (for which installer packages are provided for Raspberry Pi and Python), plus Mycroft and Snips.ai voice assistant software.
Other refinements included incorporating compact discs into the owl’s wings to provide an iridescent sheen. Slots in the case allowed Alex to feed through cable ties to attach Archie’s wings, which she says now “provide a lively bounce to the wings, in tune with his active movements (as well as my own).”
Biomimicry is often used to take the designs that nature has perfected over a period of millions of years and incorporate them into our own technology. One maker who goes by mcp on YouTube took this idea one step further and created a fish that can swim in the water like the actual creature. By carefully analyzing and studying the patterns a fish makes while it scurries through a lake, he was able to reduce these motions down to just a few joints.
The body of this DIY robotic fish was constructed from a series of four joints that each contain a single mini servo motor to control their movements. Next, an Arduino Nano was selected as the microcontroller board due to its small size and ample amounts of GPIO pins. In order for the fish to sense if there is an obstacle in the way and avoid it, the device also features “eyes” that utilize IR emitter/receiver pairs.
Once the spine of servo motors was combined with the Arduino and a set of LiPo batteries, mcp slipped over a skin made from a waterproof latex-like material that aids in moving throughout the water. In his video below, the DIY robotic fish can be seen oscillating freely through a bathtub full of water, along with a pool. His device works very well as it generates plenty of forward force to swim wherever it wants while avoiding obstacles.