[David0429] has made a very scary Raspberry Pi controlled puppet. Scary that is if you’ve seen the Saw movies where a serial killer uses one like it, called Billy, to communicate with his victims. If you haven’t, then it’s a pretty neat remote-controlled puppet-on-a-tricycle hack.
A stepper motor hidden under the front fender moves the trike by rotating the front wheel. It does this using a small 3D printed wheel that’s attached to the motor’s shaft and that presses against the trike’s wheel. Steering is done using a 3D printed gear mounted above the fender and attached to the steering column. That gear is turned by a servo motor through another gear. And another servo motor in the puppet’s head moves its mouth up and down.
[David0429] took great care to make the puppet and tricycle look like the one in the movie. Besides cutting away excess parts of the trike and painting it, he also ran all the wires inside the tubular frame, drilling and grinding out holes where needed. The puppet’s skeleton is made of wood, zip ties and hinges but with the clothes on, it’s pretty convincing. Interestingly, the puppet in the first movie was constructed with less sophistication, having been made out of paper towel rolls and papier-mâché. The only things [david0429] would like to do for next time are to quieten the motors for maximum creepiness, and to make it drive faster. However, the need for a drive system that could be hidden under the fender resulted one that could only work going slowly. We’re thinking maybe driving it using the rear wheels may make it possible provide both speed and stealth. Ideas anyone?
In any case, as you can see in the video below, the result is suitably creepy.
Robots are increasingly seeing the world outside of laboratories and factories, and most of us think we would be able to spot one relatively quickly. What if you walked past one on the street — would you recognize it for what it was? How long would it take for you to realize that homeless organ grinder was a robot?
The brainchild of [Fred Ables], Dirk the homeless robot will meander through a crowd, nodding at passers-by and occasionally — with a tilt of his hand — ask for change, churning out a few notes on his organ for those who oblige him. [Ables] controls Dirk’s interactions with others remotely from nearby, blending into the crowds that flock to see the lifelike automaton, selling the illusion that Dirk is a real human. This is often effective since — as with most homeless people — pedestrians won’t spare Dirk a second glance; the reactions of those who don’t pass him over range from confusion to anger or mirth over being so completely duped before looking for the puppeteer.
This animatronic teddy bear is the stuff of nightmares… or dreams if you’re into mutant robot toys. In either case, this project by [Erwin Ried] is charming and creepy, as he gives life to an unassuming stuffed animal by implanting it with motorized parts.
[Erwin] achieves several degrees of motion throughout the bear’s body by filling the skin with a series of 3D printed bones, conjoined by servo motors at its shoulders, elbows and neck. The motors are controlled via an Arduino running slave to a custom application written in C#. This application uses the motion tracking and facial recognition features of the Xbox Kinect, mapping the input from the puppeteer’s movement to the motors of the doll’s skeleton. Additionally, two red LEDs illuminate under the bear’s cheeks in response to the facial expression of the person controlling it, as an additional reminder that teddy feels what you feel.
In [Erwin’s] video, he demonstrates what his application sees through the Kinect’s camera side-by-side with the mechanical skeleton its controlling. The finished product isn’t something I’d soon cuddle up to at night, but looks amazing and is fun to watch in action :
Computer animation is a task both delicate and tedious, requiring the manipulation of a computer model into a series of poses over time saved as keyframes, further refined by adjusting how the computer interpolates between each frame. You need a rig (a kind of digital skeleton) to accurately control that model, and researcher [Alec Jacobson] and his team have developed a hands-on alternative to pushing pixels around.
The skeletal systems of computer animated characters consists of kinematic chains—joints that sprout from a root node out to the smallest extremity. Manipulating those joints usually requires the addition of easy-to-select control curves, which simplify the way joints rotate down the chain. Control curves do some behind-the-curtain math that allows the animator to move a character by grabbing a natural end-node, such as a hand or a foot. Lifting a character’s foot to place it on chair requires manipulating one control curve: grab foot control, move foot. Without these curves, an animator’s work is usually tripled: she has to first rotate the joint where the leg meets the hip, sticking the leg straight out, then rotate the knee back down, then rotate the ankle. A nightmare.
[Alec] and his team’s unique alternative is a system of interchangeable, 3D-printed mechanical pieces used to drive an on-screen character. The effect is that of digital puppetry, but with an eye toward precision. Their device consists of a central controller, joints, splitters, extensions, and endcaps. Joints connected to the controller appear in the 3D environment in real-time as they are assembled, and differences between the real-world rig and the model’s proportions can be adjusted in the software or through plastic extension pieces.
The plastic joints spin in all 3 directions (X,Y,Z), and record measurements via embedded Hall sensors and permanent magnets. Check out the accompanying article here (PDF) for specifics on the articulation device, then hang around after the break for a demonstration video.
Adafruit Industries just posted the first episode in a new educational series aimed at teaching kids about electronics. The episode is entitled “A is for Ampere” and teaches the basic theory behind electrical current. The subject seems like a common one for A-to-Z themed electrical tutorials. [Jeri Ellsworth] did a similar episode but hers is aimed more at the electronics hobby crowd.
[Limor] and gang (that’s [Collin Cunningham] dressed up as [Andre-Marie Ampere]) seem to be all-in on this project. The episode features ADABOT, the blue puppet which takes on the role of the student in this episode. After demonstrating a mains circuit breaker tripping the episode goes on to discuss electron flow and how current is measured.
We’re all about this type of educational opportunity. The age group at which this series is targeted have never known a day without touchscreens, they should know at least something about how those devices actually work.
I can hear the comments now: “Not a hack.” Yeah that might be true, but it’s still enormous puppets running around Berlin – that in its own right is pretty cool. The show, put on by the street theater group Royal De Luxe, is part of the 20th anniversary for the fall of the Berlin Wall. Spectators watched as the Big Giant rose from the water in search of his niece, the Little Giantess. We won’t spoil the ending, but its a happy one. Reminds us of the similar giant marionette group La Machine, and their La Princesse.