While 2020 may seem like a very futuristic year, we still don’t have robotic maids like the Jetsons’ Rosie the Robot. For his latest element14 Presents project, DJ Harrigan decided to create such a bot as a sort of animatronic character, using an ESP8266 board for interface and overall control, and a MKR ZERO to play stored audio effects.
The device features a moveable head, arms and eyes, and even has a very clever single-servo gear setup to open and close its mouth.
UI is via smartphone running a Blynk app, and Rosie’s antennas can light up along with a “beep beep” sound to let you know it needs your attention!
The Physical Twin travels on a three-wheeled chassis and mounts a four-axis arm with a brush. An operator controls the arm to dip the brush into an onboard paint container, and can then manipulate it for application.
The controller consists of a joystick for movement as well as a mini version of the arm. Four potentiometers measure arm input angles, which are duplicated on four corresponding servos on the robot. A pair of Arduino Mega boards are used for the setup — one on the mobile robot and another in the remote unit.
You can see the device in action in the videos below, showing off direct operation and the ability to play back prerecorded movements.
One of the simplest ways to make a mobile robot involves differential steering, where two wheels move at different speeds as needed to turn, and a roller on the back keeps it from tipping over. The MrK_Blockvader is an excellent take on this type of bot, demonstrated in the first clip below. It features a nice blocky body comprised out of 3D-printed parts, wheels driven by tiny gear motors, and an integrated roller ball on the back.
The MrK_Blockvader is controlled via an Arduino Nano, along with an nRF24 breakout that allows it to receive signals from a radio transmitter unit. The build includes LED lighting as well as a piezo buzzer for all the beeps and boops. It can also take advantage of various sensors if necessary.
The eventual goal is to use the MrK_Blockvader in a network of robots, hinted at in the second video with a worker at its side.
Mechanical table hockey games, where players are moved back and forth and swing their sticks with a series of knobs, can be a lot of fun; however, could one be automated? As Andrew Khorkin’s robotic build demonstrates, the answer is a definite yes — using an Arduino Mega and a dozen stepper motors to score goals on a human opponent.
The project utilizes an overhead webcam to track the position of the players and puck on the rink, with a computer used for object detection and gameplay. Each player is moved with two steppers, one of which pushes the control rod in and out, while the other twists the player to take shots.
Training the game took six months of work, which really shows in the impressive gameplay seen below.
Poisonous plants, like poison ivy, can really ruin your day. In an effort to combat this “green menace,” YouTuber Sciencish decided to create his own quadruped robot.
The robotic dog is equipped with two servos per leg, for a total eight, which enable it to move its shoulders and elbows back and forth.
An Arduino Uno controller determines leg positions via trigonometric calculation, and when in position, it dispenses weed killer via a relay and aquarium pump setup. The reservoir can also be used to hold other liquids, whether for watering duties or even to provide extra fuel to a fire.
If you’d like to build a walking biped robot, this 3D-printed design by Technovation looks like a fantastic place to start. Each leg features three servos that actuate it at the hip, knee, and ankle for a total of six degrees of freedom.
Control is handled by an Arduino Uno board that rides on top of the legs, along with a perfboard to connect to the servos directly.
Movements are calculated via inverse kinematics, meaning one simply has to input the x and z positions, and the Arduino calculates the proper servo angles. The bot is even able to take steps between two and 10 centimeters without falling over.