[Thomas] took a Geiger counter he built on a plane. Why? Because he can, much to the chagrin of airport security.
[Thomas]’ Geiger counter is built around an old Russian SBT-10A detector containing ten separate Geiger tubes. This tube was connected to a circuit containing a LiPo battery, a few high-voltage components, and an audio jack connected to the tubes themselves. When alpha, beta, or gamma radiation hits one of the Geiger tubes, an enormous click is sent to the audio jack and into the microphone jack of a small netbook.
Right after boarding a plane in Dublin, [Thomas] booted up his computer, started recording in Audacity, plugged in his Geiger counter, and stored his experiment safely in the overhead compartment. After landing in Prague a few hours later, [Thomas] saved the 247 MB .WAV file and began working on a way to convert clicks in an audio track into usable data.
The audio output on the Geiger counter overloaded the mic input on his netbook, making ‘event detection’ very easy with a small C app. After plotting all the data (seen above), [Thomas] had a complete record of the radiation on his 2-hour flight.
Because there was far less atmosphere to absorb cosmic radiation, [Thomas]’ radiation dose was 9.1 microsieverts. Much more than at sea level, but nothing even air crews need to worry about.
For just a few bucks you can add a payload to your flying toys. In this case it’s a Cessna RC plane which now has an added surprise. The first thing to be dropped was a parachute with a weight on it (for testing purposes). But there are hints of future projects that will use the same system for different purposes.
As you can see in the image above, the system depends on an additional compartment attached to the bottom of the plane. It was built from foam board to keep the weight down and connects using rare earth magnets. The bottom of the enclosure acts as the door, hinging on a servo motor with a bamboo skewer as the axle. So far the test drops have gone pretty well, but some more work needs to be done with the parachute design. It only opens about 60% of the time. We can sympathize, having had to work out some of our own parachute issues.
Don’t miss video from the plane as well as the ground after the break.
Continue reading “Adding payload to an RC cessna”
[G. Eric Rogers] is a radar-systems engineer who just happens to live within sight of the aircraft approach path for the local airport. We wonder if that was one of the criteria when looking for a home? Naturally, he wanted his own home-based system for tracking the airplanes. He ended up repurposing a motorized telescope for this purpose.
The system does not actually use Radar for tracking. Instead, the camera strapped to the telescope is feeding a video experimenter shield. A tracking algorithm analyzes the video and extrapolates vector data. From there, the base unit can be controlled by the Arduino via an RS232 interface.
There are some bugs in the system right now. The Arduino has something of an ADHD problem, losing interesting and going to sleep in the middle of the tracking process. [Eric’s] workaround uses the RS232 board to periodically reset the Arduino, but he hopes to squash this bug soon.
Have a habit of hitting the bottle before getting into the cockpit? Find that your mind wanders mid-flight? Lack the hand-eye coordination to keep that RC creation of yours in the air? Worry not, you can build this flyer and crash it with impunity.
[HammyDude] built the RC aircraft out of laminated foam board. He’s had it for years and it’s survived multiple crashes. You can see the one real injury suffered, a snapped fuselage at the leading edge of the wings. He repaired it with popsicle sticks and it’s been going strong ever since.
In addition to the wooden reinforcements he’s covered the fuselage with fibrous packing tape (you know, the stuff with the strings running in it). There’s also a carbon fiber tube at the leading edge of each wing. It’s light, strong, and robust (with the exception of the propeller of which he’s broken about 10).
Check out the video after the break for an explanation of the aircraft, list of materials, and HD images of the patterns you need to make them yourself. The only thing you won’t see is flight footage.
Continue reading “Eight-dollar airplane for really bad pilots”
Along with hobby electronics, flying RC planes is one of [Diederich’s] favorite hobbies. When out in the field, he prefers to use an Aurora 9 radio controller, and while the remote is great, he was a bit disappointed in Hitec’s telemetry sensor lineup. He says that the sensors are pretty decent, though limited, and he was positive he could build a better telemetry solution.
His sensor board is completely open source, and comes with a long list of features. First and foremost, it emulates all of the messages that can be sent to the radio controller by Hitec’s off the shelf models, making it a simple drop-in replacement. He uses an ATMega8L microcontroller to run the show, including all sorts of input pins and connectors to support GPS as well as voltage and current monitoring.
He has made a DIY kit available for purchase online, but all of the sensor’s schematics and a BOM are available for free, should you desire to roll your own.
We love seeing DIYers show up manufacturers in this way, especially when they share the goods with their fellow hobbyists. Nice job!
[lenny] decided to build a 555-based auto-firing mouse based on a 555 after seeing a similar PIC-based project we posted earlier. Lenny’s version is self-contained in one mouse without requiring a second mouse to act as the rapid-fire button. It uses only a handful of components, costs less than $5 to build, and doesn’t require any programming.
But then, [wfdudley] shakes things up a bit. He added a 4022 counter IC and some diodes to act as logical “OR” gates in order to create a unique blinking pattern (short-short-long) for the lights on a friend’s RC airplane. While this project involves more components, it’s definitely a trickier problem to solve with a 555 timer IC. We love seeing people choosing simplicity in design over popular off-the-shelf microcontroller frameworks as these two have done.
Don’t forget, the 555 Design Contest is still going strong, and you’ve got the entire month of February to submit your awesome designs. We wanted to highlight two of the more clever 555-based hacks that we’ve had in our backlog for a while, though.
This hack’s old as dirt to be sure, but new to us and a great accomplishment. The plane above, which is meant to fly without an operator, has been given RC control thanks to parts from that little car. The transmitter and receiver pair are the obvious transplant, but how do you add steering to a $7 plane that wasn’t manufactured to have that feature? The tail was cut and reconnected with mylar hinges to turn it into a rudder. A rare earth magnet and a coil are also thrown into the mix to provide movement. Basically this is a simple solenoid where the coil pushes against the magnet when energized, actuating the rudder. This in combination with an upgraded motor allows for both speed control and yaw. It doesn’t look like you can control roll and pitch but what more can you really expect?
This would be a nice first step on that path to building an epic flying camera rig.