To capture images of bullets “interacting” with various objects, photographic hacker Tyler Gerritsen created an impressive chronograph rig, able to measure the speed of a bullet launched from a rifle at 1000 meters per second. While the concept of measuring time from one sensor to another isn’t new, implementation at this speed required some interesting tricks.
To accomplish this feat, Gerritsen designed his own sensor array using photodiodes in a reverse-biased setup, and even calibrated the clock speed of the Arduino Uno for control in order to account for any variation. Finally, the time between triggering a flash and light actually appearing had to be compensated for in the code, a different value for each type of equipment.
After finding that purchasing a tracking device for his satellite dish would be quite expensive, YouTuber “Tysonpower” decided to simply build one himself. What he came up is an assembly made with 3D-printed parts and extruded aluminum that uses a pair of NEMA23 stepper motors for movement.
While it doesn’t quite work with the dish itself due to its offset weight, the concept was successfully used to track weather satellites using a VHF Yagi antenna.
If you’ve been interested in creating a word clock for your home, then perhaps this neat build by “oliverb” will be the perfect place to start.
The clock, powered by an Arduino Nano along with a RTC module, is capable of displaying the time by spelling it out as you expect, or can use the letters as a matrix in order to show the time in digital format. These letter-dots can even be configured to form an “analog” clock if you prefer.
But that’s not all. The device can reveal the temperature and humidity, as well as play games like Tetris. Be sure to see it in action below!
What’s the best way to dispose of the dust that is produced when cutting with power tools? YouTuber Bob Claggett’s answer is to automate the process entirely, using a series of PVC sewer pipes to transport air to a central vacuum system, along with an Arduino Uno for control.
Airflow is regulated via a blast gate for each power tool, which is opened and shut using a hobby-style servo and custom linkage system. The powerful dust collector is controlled with the help of a relay.
Cleverly, a voltage sensor is employed for each power tool needing dust collection, allowing the Arduino to turn on the system and decide which gate to open without any human interaction.
Water is essential to life on earth, and making sure our rivers and lakes are free from pollution is therefore quite important. For environmental monitoring, students from Bergen County Academics Magnet High School have come up with the Intelli-Buoy system that can track water turbidity, pH, oxygen, and temperature levels for analysis. It can also keep tabs on wind speed and rain stats for possible correlation.
The floating device uses a pair of Arduino Unos with an SD card shield mounted on each in order to record these statistics over several days, and it’s designed with two external USB ports for easy access.
Be sure to check out this orange PVC sensor assembly the video seen here.