Hopefully Detect Trolls Before They Devour You

In the cold and mysterious wilderness of Norway, it pays to be ready for anything–especially heavy-walking trolls. The team at [nullohm] decided to prepare thoroughly for their trek into the woods to witness the Leonids meteor shower by putting together an Arduino-based “troll detector”.

The device is based on the superstition of hammering a steel spike into a tree to keep trolls away from camp. This goes one step further by including an accelerometer and LED indicators so that you can tell exactly what type of troll is just about to feast upon your tender human flesh.

When the detector is installed into a nearby tree, it takes an average seismic measurement and then looks for telltale footfalls. Even if you’re not concerned with perpetuating superstitions, you might find a use for the source code for simple seismic activity monitoring at home to supplement your miniature seismic reflector.

Gum Ball Maze Updated… Now With Robots!

In what is surely becoming an ever-growing Rube Goldberg machine, [Dan] updated his gum ball dispenser to include a robot arm. We looked in on this human lab-rat experiment that rewards successful maze navigation with bubble-gum just about a year ago. As you can seen in the video after the break he’s added several new features to delight users. The original had a maze actuated by an accelerometer and that remains the same. But when the device fires up, the wooden ball is moved to the start of the maze by a Lynxmotion robotic arm. That arm is mounted on rails so it can also move to deliver the gum ball after a successful run. There’s also an anti-jamming feature that shakes the gum ball dispenser to ensure you don’t come up empty.

Whether playing chess or being controlled by a mouse the Lynxmotion has been quite popular lately. [Dan’s] solution uses a vacuum pump to grab onto the spheres (both wooden and gum), similar to the method used with the CNC pick and place from a while back.

Continue reading “Gum Ball Maze Updated… Now With Robots!”

Easy Quadrotor Helicopter Instructions

Here’s a great tutorial on building your own quadrotor helicopter. This build isn’t necessarily less expensive than others we’ve seen since quality motors, propellers, and control circuitry aren’t cheap. But the design and assembly is well documented and presents a well-planned building procedure. The carbon-fiber tubes that make up the frame have extensions to protect the motors and propellers in the event of a crash. The Arduino, IMU, and transceiver are all tucked away between two aluminum body plates as well. They only thing missing is a solid methodology for tuning the four motors, a critical procedure that is just touched up at the end of the article.

Hexapod Controlled By Android And IPhone

[youtube=http://www.youtube.com/watch?v=NvEBUd_EqbQ]

This video is a blatant example of having too many high-end toys but we love it anyway. [Robert Stephenson] is controlling a rather awesome-looking hexapod via a Bluetooth connection to his HTC Hero. The app allows on-screen selections to decide which portion of the robot will move as a result of accelerometer data from the handheld. The only thing we saw that was missing is a camera feed to the phone.

But this hack doesn’t stop there. The Hero can be used to host a WiFi network while still connected to the hexapod. The second half of the video shows an iPod Touch connecting via WiFi and controlling the bot. Now head on over to the laser cutter to start that hexapod build, and finish up by getting elbow-deep into some Android development.

One-handed GameCube Controller

[Hasse] built a one-handed video game controller for his brother. He fit everything he needed into the body of an existing controller and came up with a very usable system. The controller will be right-hand only, so the left shoulder button was moved underneath the right side where your middle finger can get at it. This leaves the d-pad and the left analog stick to account for. By combining an ATtiny44A, an accelerometer, and a digital to analog converter the controller can sense motion. The microcontroller reads in the accelerometer data, gives user feedback via four added LEDs on the d-pad, and the DAC feeds the appropriate signals back into the controller as if you were using the stick. There is even a switch to select whether the motion data is mapped to the analog stick or to the d-pad. We’ve included a demo video after the break.

Find that you also need some one-armed typing assistance? Check out this half-qwerty keyboard hack. Continue reading “One-handed GameCube Controller”

Hands-free Input

This is a concept input device that [Tech B] built for disabled users. The device uses an accelerometer along with a piezo sensor (right click) and a push button (left click) to function as a mouse. The Arduino that resides in a breadboard on the side of the hat communicates with the computer over a serial connection, using PySerial to translate the microcontroller data into cursor commands with the power and ease of the Python programming language.

During development [Tech B] made a proof-of-concept video using a Basic Stamp which you can watch after the break. He found that this input device was less complicated, more accurate, and much less resource intensive than his webcam IR tracking system.

Adding Motion Control To An RC Transmitter

If your soldering skills are up to snuff you can add a motion control feature to your radio controlled transmitter. [Starlino] used a combination accelerometer and gyroscope module as an alternate source of analog control information. He built a filter to dial in the analog voltage range to match that of one of the sticks on the controller. A switch is used to disconnect the signal when motion input is not desired. This would be a nice addition to one of those more creative aerial hacks.