Halloween Links: October 30th, 2013

hackaday-links-chain

Happy Halloween from everyone at Hackaday! To help you enjoy the holiday here are a few festive links:

[Mike Kohn] whipped up a set of motion tracking eyeballs to make his decor extra creepy.

There’s not much to this jet-pack costume but the results are pretty amusing.

The eyes on [Tim Butler’s] skeleton prop don’t follow you around the room, but they do use a PIR sensor to light up the skull.

Speaking of skulls, [Tom] is using some real skulls as decorations. He also added lights where the eyeballs should be, but he is using a photoresistor and comparator to turn on some LEDs.

[Clark] built a Mecha Robot Warrior costume for his son. With all of those LED strips we think he’ll be pretty safe when crossing the street!

And finally, [Jesse] added a lot to his prop in order to produce a Sinister Joker. That’s Joker-as-in-cards and not as in Batman. It’s got an IR distance sensor as a trigger, with a motor to move the wrist, lights for the eyes, and a sound shield to give it a disturbing voice.

Inexpensive Robot Tracking System Is Swarm Ready

RobotWebcam

[Ladvien] has figured an inexpensive way to control a robot from a remote PC with a static webcam. Inspired by swarming robot videos such as those from the UPENN Grasp lab, [Ladvien] wanted to build his own static camera based system. He’s also managed to create one of the more eclectic Instructables we’ve seen. You don’t often find pseudo code for robot suicide mixed in with the project instructions.

Fixed cameras are used in many motion capture systems, such as the Vicon system used by numerous film, game, and animation studios. Vicon and similar systems cost tens of thousands of dollars. This was a bit outside [Ladvien’s] budget. He set about building his own system from scratch. The first step was the hardest – obtaining permission from his wife to screw a webcam into the ceiling. With that problem overcome, [Ladvien] brought openCV and python to bear. He created Overlord, his webcam vision and control system. A vision system with nothing to control would be rather boring, so [Ladvien] created DotMuncher, Overlord’s radio controlled robot slave.

The basic processing system is rather simple. DotMuncher carries a magnetometer on board, which it uses to send heading information to Overlord. Overlord is pre-calibrated with an offset from magnetic north to “video game north” (toward the top of the screen). Overlord then uses openCV’s color detection to find DotMuncher in the current scene.
Overlord finally generates a virtual “Dot” on screen, and directs DotMuncher to drive over to it. When the robot gets to the dot, it is considered munched, and a new dot is generated.

Continue reading “Inexpensive Robot Tracking System Is Swarm Ready”

Walter Is A Robot Head Built From Scratch.

walter

[Chris] has put together a robot head that is impressive at first sight. [Chris’] robot, Walter II, becomes even more impressive when you realize that [Chris] built every single part from scratch. Many of Walter’s parts were created using machines [Chris] built himself. Walter is a robot neck and head. His upper neck joint is based upon three bevel gears.Two steppers drive the side gears. When the steppers are driven in the same direction, Walter’s head nods. When they are driven in opposite directions, the head turns. The end result allows Walter’s head to be panned and tilted into almost any position.

A second pair of motors raise and lower Walter’s neck via a chain drive. What isn’t immediately visible is the fact that a system of gears and belts maintains the tilt on Walter’s head as his lower neck joint is actuated. For example, if Walter’s head is facing directly forward with his neck raised, one would expect him to be facing the ground when the neck is lowered. The gear/belt system ensures that Walter will still be facing forward when the neck joint reaches its lower limit. All this happens without any movement of the neck motors. [Chris] definitely put a lot of thought into the mechanical design of this system.

Continue reading “Walter Is A Robot Head Built From Scratch.”

Quadruped Robot Thinks It’s A Puppy

puppybotBack 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!

Continue reading “Quadruped Robot Thinks It’s A Puppy”

Turbot Is A Beam/Picaxe Hybrid

[James] wanted to build a BEAM turbot. He ran into some problems with the BEAM circuitry though, and ended up with a BEAM/Picaxe hybrid.
Beam robotics
are the brainchild of Mark Tilden. The acronym stands for Biology, Electronics, Aesthetics, and Mechanics. BEAM based bots were very popular with hobbyists in the 90’s and early 2000’s, but popularity has since died down. BEAM robots tend not to use microcontrollers, instead attempting to simplify things down to the lowest number of elements.

[James’] turbot uses a miller solar engine. The original design used the engine to drive a Solar Turbot Latch. [James’] problem was that the photodiode “eyes” of the robot were not properly enabling the 74AC245 to pass current to the motor. Since the robot was built in a tiny space, debugging the circuit was extremely hard. After struggling with the ‘245 for some time, [James] decided to swich out the BEAM circuit for a Picaxe microcontroller.

The Picaxe can only sink or source about 20ma per pin, which is slightly less than the no load current of [James’] motors. To make up for this, he ganged up four pins per motor. There was some risk in the motors blowing up the Picaxe. However between the lightly loaded gearmotors and low current solar panels it seems to be working just fine.  Overall the bot is a very clean, compact build. Jump past the break to check out its really smooth crablike walking action.

Continue reading “Turbot Is A Beam/Picaxe Hybrid”

Atlas Survives The Wrecking Ball

[Boston Dynamics] has been just full of videos over the last few days. They’ve dropped updates on Atlas and LS3 in addition to the WildCat update we already featured.

This video shows updates to the Atlas robot. This is to be a simplified version of the atlas, as compared to the robots sent off to competitors in the DARPA robotics challenge. Arms have been replaced with weights. It appears that this update focuses on Atlas’ balancing and handling on rough terrain. Atlas walks gingerly, over some crushed cinder blocks – possibly the same ones we saw BigDog throwing around recently. There are a few tense moments, but Atlas manages to get through unscathed.

The real scary part (for us) is watching Atlas get hit with a weighted ball. We’re assuming the 20 on the ball indicates pounds. Imagine getting hit from the side with a 20lb swinging weight. Would you be able to stand up? Did we mention Atlas did this all while standing on one foot? Atlas takes it in stride though – waving its arms to maintain balance in a very human manner.  Notable is the balance system. Atlas never lifts its foot off the ground. This is slightly different from the bouncing/hopping system of balance we’ve come to know and love in [Boston Dynamics’] other robots.  Continue reading “Atlas Survives The Wrecking Ball”

Boston Dynamics Takes WildCat Outside

wildcat

[Boston Dynamics] has released a video of their latest robot, which means it’s time to go hide in bed before this thing comes to get us. The new video features WildCat, which is apparently the evolution of the Cheetah robot we saw last year. Cheetah was an indoor cat, tethered by power, data, and hydraulic lines while running on a treadmill. WildCat has been released to terrorize people explore the great outdoors

Reminiscent of the early videos of BigDog, WildCat is currently powered by an internal combustion engine. The engine drives a hydraulic system, which then actuates the robot’s legs and front/rear pods. The beauty of a system like this is that switching to an electric motor is simple – just replace the IC engine. While we’re sure this would make a much more stealthy cat, weight and run time could be issues. Moving the power system onboard has also slowed down WildCat a bit. Cheetah was able to reach 28 MPH while WildCat can only muster 16 MPH.

WildCat is part of DARPA’s maximum mobility and manipulation program. The research appears to be focused on improving the gaits the robot uses to move at various speeds. The video highlights both bounding and galloping.  Slo-mo sections show all four of WildCat’s legs leaving the ground, which is the suspension phase of a classic gallop gait. Control isn’t perfect yet, as WildCat tumbles at one point in the video.  It gets right back up though – ready for more.

Continue reading “Boston Dynamics Takes WildCat Outside”