Anyone who’s ever tried to build a bipedal robot will quickly start pulling their own hair out. There are usually a lot of servos involved, and controlling them all in a cohesive way is frustrating to say the least. [Mark] had this problem while trying to get his robot to dance, and to solve it he built a control system for a simple bipedal robot that helps solve this problem.
[Mark]’s robot has six servo motors per leg, for a total of 12 degrees of freedom. Commands are sent to the robot with an RC radio, and the control board that he built, called the Smart Servo Controller, receives the signals and controls the servos appropriately. There are 14 outputs for servos, operating at 12 bits and 50 Hz each, as well as 8 input channels. The servo controller can be programmed on a computer with user-selectable curves for various behaviors for each of the servos on the project. This eliminates the need to write cumbersome programs for simple robot movements, and it looks like it does a pretty good job!
Full disclosure: [Mark] currently has this project up on Kickstarter, but it is a unique take on complex robot control that could help out in a lot of different ways. Since you don’t need to code anything, it could lower the entry barrier for this type of project, possibly opening it up to kids or school projects. Beyond that, even veterans of these types of projects could benefit by not having to do as much brute-force work to get their creations up and moving around!
Continue reading “Walk Your Pet Robot”
For the last few years now, the 3D printing community has been searching for a groundbreaking application for out little boxes of plastic squirting goodness. On of the most interesting applications the community has stumbled upon is prosthetics.
There have been a lot of people warming up their 3D printers and laser cutters to make prosthetic limbs in recent years. For [OpenBionics]’ entry for The Hackaday Prize, they’re building a prosthetic hand that costs less than $200, weighs less than 300 grams, and can be easily fabricated with 3D printers and laser cutters.
The human hand is the most complex end-effector on the planet, and emulating its range of motion is a difficult task. Still, the [OpenBionics] team is working hard to properly emulate a thumb with three degrees of freedom, putting 144 different grasps on the hand, and making their hand useful with soft fingertips.
Even with all this capability, [OpenBionic]’s robotic hand – motors and all – is about the same size as a normal human hand. That’s incredible, especially when you consider the motors for your hand – muscles – are all in your arm.
The team has put together a video demoing the capabilities of their hand. It’s somewhat remarkable, and able to do everything from lift a coffee cup to holding a pen. You can check that video out below.
Continue reading “Hackaday Prize Entry: OpenBionics”
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.
[Radomir]’s entry for The Hackaday Prize aims to fix this bizarre oversight of scientific and technological progress. He’s designed a small, inexpensive, but very well designed quadrupod robot that will put full reverse kinematics on your desk for under $50.
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.
Microcontroller-based projects don’t have to be fancy to be fantastic. Case in point: [r0d0t]’s “Musicomatic: the random jazz machine“. Clever programming and a nice case can transform a few servos and a microcontroller into something delightful.
Hardware-wise, there’s really nothing to see here; a speaker and some servos are hooked up to an ATmega328. We think it’s cute to have the microcontroller control its own power supply through a relay, but honestly a MOSFET in place of the relay or better still using the AVR’s shutdown sleep mode would be the way to go.
Nope, where this project shines is the programming. Technically, it might make some of you cringe — full of blocking delays and other coding “taboos”. But none of that matters, because [r0d0t] put his work in where it counts: the music. You simply must hear it for yourself in the clip after the break.
The basis of making music that humans like is rhythm, so [r0d0t] doesn’t leave this entirely to chance. The array “rhythms” has seven beat patterns that get randomly selected. The other thing humans like is predictability and repetition, so choruses and “improvs” repeat as well. All of the random notes are constrained to the pentatonic scale, which keeps it from ever sounding too bad. (The secret sauce of Kenny G.)
In short, [r0d0t] packs a lot of basic music theory into a very basic device, and comes up with something transcendent. We’re a bit reminded of the Yellow Drum Machine robot, and that’s high praise. Both projects are testaments to building something simple and then investing the time and effort into the code to make the project awesome.
For another slice of [r0d0t]’s excellent minimalist pie, check out his take on the classic Snake game: Twisted Snake.
Continue reading “Tiny Robot Jazz”
You might think we’re sinking to lowest-common-denominator, click-bait headlines like the rest of the online press. We’re not. The New York Times Video Notebook series has a story on camel racing that you’ve just got to see in the video after the break.
Previously, the camel races in Abu Dhabi had used small children as jockeys because they’re lightweight. Unfortunately, this lead to illegal trafficking of small children, mostly orphans. That won’t do. So they came up with a technological solution.
Strap a cordless drill with a purpose-built whip in the chuck onto the back of your camel. Add a car-remote keyfob to activate, and a two-way radio so that you can shout encouragement into your animal’s ear at just the right times. Now just chase the racers down the highway in an SUV and it’s like you’re there on the camel’s back!
We love the little silk suits that the drillbot-jockeys get to wear, but we’re not sure that cordless drills with walkie-talkies and remote controls count as “robots” really, because they don’t do anything autonomous. We think they’re more accurately described as “telepresence agents”.
Continue reading “Robot Camel Jockeys”
One of the recurring themes of science fiction is the robot. From such icons as C-3PO and R2D2 in Star Wars to WALL-E and Eve, robots have always had a certain appeal. Inexpensive microcontrollers like the Arduino have opened up the world of robotics to more people. [JohnFin] has done just this. By linking two Arduinos as the brain, he has created a voice controlled robot he calls S.P.A.R.C. (Sentry/Project Assistant/Robot Companion).
It began when he received a robotic arm for Christmas and was disappointed by it. Instead of simply building a better arm, he got “carried away” and built an entire robot instead. The entire project took three months, most of which he spent learning programming.
SPARC has three sonar sensors for detecting obstacles and movement, an arm and a couple of interchangeable hands for holding objects, and an EasyVR Arduino Shield for the voice control. The robot’s “eyes” are an LED ‘KITT’ scanner and an AN6884 VU meter chip that flashes the “eyes” when the robot speaks. It carries an onboard smartphone to look up weather, play music from the phone’s SD card, and GPS functions.
SPARC can respond to a range of commands and games including “follow me” and “singing.” [JohnFin] has also added a “sequencer” function to record and playback a series of commands. A video of this feature can be found after the break.
Continue reading “SPARC: A Voice Controlled Robot Sings Sweetly in DTMF”
Wheeled and tracked robots are easy mode, and thanks to some helpful online tutorials for inverse kinematics, building quadruped, hexapod, and octopod robots is getting easier and easier. [deshipu] came up with what is probably the simplest quadruped robot ever. It’s designed to be a walking robot that’s as cheap and as simple to build as possible.
The biggest problem with walking robots is simply the frame. Where a wheeled robot is basically a model car, a walking robot needs legs, joints, and a sturdy frame to attach everything to. While there are laser cut hexapod frames out there, [deshipu]’s Tote robot uses servos for most of the skeleton. The servos are connected to each other by servo horns and screws.
The electronics are based on an Arduino Pro Mini, with a PCB for turning the Arduino’s pins into servo headers. Other than that, a 1000uF cap keeps brownouts from happening, and a 1S LiPo cell provides the power.
Electronics are easy, and the inverse kinematics and walking algorithms aren’t. For that, [deshipu] has a few tutorials for these topics. It’s a very complete guide to building a quadruped robot, but it’s still a work in progress. That’s okay, because [deshipu] says it will probably remain a work in progress until every kid on Earth builds one.