__ __ __ ___ / // /__ _____/ /__ ___ _ / _ \___ ___ __ / _ / _ `/ __/ '_/ / _ `/ / // / _ `/ // / /_//_/\_,_/\__/_/\_\ \_,_/ /____/\_,_/\_, / retro edition /___/Now optimized for embedded devices!!
| About | Successes | Retrocomputing guide | Email Hackaday |
Unhappy with the 120 degree range of movement for this digital servo motor [Malte] set out to expand its flexibility. He settled upon a hack that alters the feedback potentiometer in order to give the motor a wider range (translated).
The test video (embedded after the break) shows tick marks for before and after his alterations. You can see that the wider tick marks get much closer to the 180 degree range he’s interested in. The control method is no different than it was before, the internal circuitry is still listening for a control signal with pulses between 1 and 2ms to establish the position of the servo horn. [Malte] added resistors on the two outside legs of the feedback potentiometer. This is what that control circuit measures in order to judge the position of the servo horn. He’s using 1.6k Ohm resistors in this demonstration. But he didn’t just drop them in willy-nilly. His writeup discusses the calculations he used to determine the target voltage for the motor position he wants.
If you’re into ham radio and want it when you’re on the go give this antenna mount a try. [Cirictech] started with a design from the November 2009 issue of QST and added his own fabrication touches. Everything except the antenna itself is available from the hardware store for just a few bucks, and you should be able to complete this project in a flash. This makes us wonder what the antenna for the 47 GHz band radio setup would look like.
Being a dedicated father, soccer coach, general tinkerer, and electrical engineer, [Dave] decided to build a soccer simulator video game for his son’s 6th birthday party. The concept behind the game is to put a soccer ball on a tee and have an eager line of six-year-olds kick the ball into the goal. A video of a goalie is projected behind the net, and sensors in the goal will determine if the player scored a goal or not.
The first part of [Dave]‘s project was getting footage of a goalie diving for a soccer ball. Luckily, [Dave] is friends with [Mark Macdonald], a former NCAA goalie. After 10 minutes in the park with [Mark] and a 720p camera, [Dave] had all the footage needed to build his video game.
To detect where the soccer ball passed into the goal, [Dave] built a small soccer goal studded with infrared LEDs and infrared beam break sensors. Combined with a small switch underneath the ball tee, the software knows the time of flight and where the ball crossed into the goal. The game processes these two numbers to determine if it’s a goal, or was caught by the retired pro goalie.
The kids at the birthday party lined up to play [Dave]‘s soccer game – a huge achievement getting 6-year-olds to wait their turn. We admit that we’d like to have a go at this game, although we’re pretty sure we saw an arcade version of this game years and years ago.
[David Forbes] is no stranger to the weird and esoteric, so he created a color LED TV built into a lab coat. He plans on bringing it to Burning Man next month.
The RGB LEDs are mounted narrow flex boards, providing a 160×120 pixel NTSC display. Video processing is taken care of by an Xilinx FPGA that takes the YCrCb video feed from a video iPod and converts it into four separate RGB streams for the front, back, and the two sides. The requisite controls for brightness and color are on the shoulders.
Of course, the build wouldn’t be over-the-top without the ability to plug a Nintendo into a lab coat, so there’s an NTSC input on an RCA jack. Everything is powered by two 11.1 V, 5Ah radio-control LiPo battery packs that should power this for a while.
Check out a video of the LED lab coat below.
This image was not made in post production, but captured during a long camera exposure. The method uses stencils to add components to a picture. [Alex] built a jig for his camera from a cardboard box. This jig positions a large frame in front of the camera lens where a printed stencil can be inserted. He printed two identical sheets of paper with black covering the area all around the 8-bit joggers. When properly aligned and inserted in the jig, the black parts of the stencil will act to mask the areas where he wants to capture the natural surroundings of the image. Once the camera shutter is triggered, he uses a flash to illuminated the stencil, then removes the the paper image from the jig and ambient light from the dark surrounding is captured during the remainder of the 20-30 second exposure time. The real trick is getting the light levels between the flash and the ambient light to balance and produce a result like the one seen above.
Is anyone else hearing the Punch Out cut-scene music in their heads right about now?