In the drag racing world, a Christmas tree is the post at the start line that sequentially lights up a set of yellow lights followed shortly after by a green light to tell the drivers to go, the lights obviously giving it its seasonal name. Included at the base of the tree are lasers to detect the presence of the cars.
[Mike] not only made his own Christmas tree for his RC cars, but he even made an end-of-track circuit with LED displays telling the cars how long they took. Both start and finish hardware are controlled by Pololu Wixel boards which has TI CC2511F32 microcontrollers with built-in 2.4 GHz radios for wireless communications.
In addition to the LEDs, the Christmas tree has a laser beam using a 650nm red laser diode for each car at the start line that’s aimed at a TEPT5600 phototransistor. If a car crosses its beam before the green light then a red light signals the car’s disqualification.
The end-of-track circuit has 7-segment displays for each car’s time. [Mike] designed the system so that the Christmas tree’s microcontroller tells the end-of-track circuit’s microcontroller when to reset the times, start the times, and clear the times should there be a disqualification. The finish line controller has lasers and phototransistors just like the starting line to stop the timers.
Oh, and did we mention that he also included 1980’s car racing game sounds? To see and hear it all in action check out the video after the break. If the cars seem a little drunk it’s because pushing left or right on the controller turns the wheel’s fully left or right.
Continue reading “RC Drag Racing Christmas Tree and Speed Trap”
The yuletide fire is out, so we’re starting to receive this year’s Christmas hacks. [Chris] sent us his awesome video-mapped tree lighting hack. His project made clever use of a bunch of cool tools, so even if you’re not thinking forward to next December, it’s worth a look. Still images don’t do it justice; check out the video below the break.
The end result is an addressable string of WS2812B LEDs connected up to a Raspberry Pi Zero that can display a video image even though it’s wrapped around a roughly cone-shaped (pine) object. But this is actually more impressive than you’d think at first; how would you map a flat image to a string of LEDs wrapped around a tree?
[Chris]’s solution was to write a routine that lit up the LEDs in a unique pattern and then detected them using OpenCV and a webcam, making the mapping directly. He then samples images from a video at exactly the points where the pixels are located on the tree, and sends this data out to the LEDs.
The basic framework here should transform fairly easily into a generic image-mapping procedure with randomly located LEDs, so we think it’s a hack that’ll outlast the season. And because it runs on the Pi Zero, everything is in Python so it’d be a good project for beginners to replicate. However, the code section on the project page still lists it as coming soon. We hope so!
Continue reading “Must-Have Overkill Christmas Tree Lights”
[Jordan Wills] was tasked by his company, Silicon Labs, to build some Christmas Baubles to give away to co-workers. While the commissioned units were designed to be simple battery and LED affairs, he decided to make one of his own with bells and whistles. His Mario themed Christmas Ornament uses a Silicon Labs FM972 micro controller, capacitive sensing, PWM controlled 8 bit audio, and blinky lights.
The interesting part is some of the construction techniques that he used. The finger-joint style cube is built from circuit boards. Electrical connections between panels were routed using solder wicking copper braid. That’s a interesting trick which we’ll keep in mind along with some of our favorite creative structural uses of PCB.
The top of the cube has four LED’s which light up the Mario “Question Mark” symbols on the four sides of the cube while the base contains all of the electronics. The outside of the base piece was a large copper plane to act as the capacitive sensing element. This meant all electronics needed to be surface mounted with tracks laid out on one side – which posed some layout challenges. Adding the Capacitive sense function was a cinch thanks to support from the in-house design team. PWM output from the micro controller takes care of audio, and the output is routed through a buffer to boost the signal. A bandpass filter then cleans up the PWM output before feeding it to the speaker.
Continue reading “Christmas Bauble is neither spherical nor runs Arduino”
When [hkdcsf] was a teenager, he made a Christmas star with an up counter driving decoder logic and using transistors to light LEDs in festive patterns. He’s revisited this project using modern techniques including a microcontroller, a DC/DC converter, and constant current LED drivers.
The project uses two AA batteries, and that’s what makes the DC/DC converter necessary. Blue LEDs have a forward voltage of just over 3V, and the LED driver chip requires about 0.6V of overhead. Two fresh AAs will run a tad above 3V, but as they discharge, or if he’s using rechargeables, there just won’t be enough potential. To make sure the star works even with whatever LEDs are chosen, the converter takes the nominal 3V from the batteries and converts it to 3.71V.
Continue reading “Christmas Star uses Two AA Batteries”
Traditionally, getting into the hobby of flying model aircraft required spending some serious coin, not to mention hours and hours of building and learning. All of that leading up to a white-knuckled, hair raising maiden flight. If you were extremely lucky, you’d head home with only a slightly damaged plane – but many of us did a nice death spiral straight into the ground – all just so we could go home, and then start all over. Perhaps one of the reasons we’re seeing so many (negative) drone related news stories recently is that the price of admission to join the club of flying machines has never been so low. That, and there always seems to be one kid in the class that wants to ruin it for the rest of us.
This year the FAA expects about a million people to wake up Christmas morning with a drone under the tree. And that’s a lot of chances for people to mess up. So if you’re planning on taking a drone up this year, you might want to watch the video after the break; Or just forward it to those that you think need to see it. If you’re into any sort of flying models you should already have [FliteTest] in your YouTube subscriptions – they have some really informative video, especially for the beginner wanting to get into the hobby.
This video guide is meant to be just a short introduction of what not to do. Obviously it doesn’t cover everything. And we wouldn’t be looking out for our readers if we didn’t say that your local laws may vary – so do your homework, stay safe, and don’t be a drone noob.
Continue reading “Don’t be a Drone Noob this Christmas”
[JoshBaker] wanted to make something special for his brother this past Christmas. He decided on making a wooden game board version of the Settlers of Catan game. [Josh] used CorelDraw to construct the vector images needed for the board. Then, he set out cutting the base, engraving and cutting out the many wooden pieces with a laser cutter. All the pieces were stained and then sealed with polyurethane. He assembled the base so that the removable hex tiles, ports, and resource numbers sit nicely in the recessed parts and don’t shift during gameplay. He complemented the board with tokens and game pieces that he hand-painted. [Josh] also created a new set of cards to fit with the board’s aesthetic.
The board is done incredibly well, not to mention beautiful to look at. The hex tiles’ designs are very detailed. The stained and engraved wood really adds to the atmosphere of the game. We featured a coffee table that would be perfect to play it on. [Josh] has listed all of the vector files for the version he gave his brother, as well as additional ones for the Cities and Knights Expansion. We wish we could have seen the look on his brother’s face when he got such an awesome Christmas gift!
Have we seen any Christmas village hacks before? None come to mind and our Google-fu didn’t turn up any either. No matter, even if there were a handful this would rank quite high. [Kyle Anderson] built models of the homes each of his loved-ones inhabit. Each model lights up when its occupant is at home.
This reminds us of the Weasley Clock, itself a popular concept to hack on. The idea is that each family member’s location is shown with a unique clock hand and a set of whimsical locations on the clock face.
The Etherhouse, as [Kyle] calls it, performs a similar action. The WiFi access point in each loved one’s home is monitored for their smart phone. When it is detected, the light for their home model is illuminated. Since each person has their own copy of the village, everyone knows who is home and who is away.
Continue reading “Christmas Village Spin on the Weasley Clock”