Custom 3D printed magnetic encoder disks for robotics projects

A how-to on making a custom DIY magnetic disk encoder by Erich Styger: I’m making great progress with the firmware for the new Mini Sumo Robot (see “New Concept for 2018 Mini Sumo Roboter“). The goal is a versatile and low-cost Mini Sumo robot, and the robot comes with the feature of magnetic position encoders. […]

Programming STM32F103 Blue Pill using USB bootloader and PlatformIO

Coyt Barringer wrote a post on his blog showing how he program the Blue Pill STM32F103 using USB Bootloader and PlatformIO: This is the infamous Blue Pill board – a $2 ARM STM32F103 development board with all the capabilities of a Teensy 3.x at a fraction of the price of an Arduino. So what’s the […]

How to configure I2C sensors with Arduino

Edward Mallon writes: I’ve spent the last year in the ‘uncanny valley’ of the Arduino. That’s the point where you understand the tutorials at Arduino.cc, but still don’t get much from the material on gitHub because trained programmers would never stoop to using the wire.h library when they could just roll their own in native […]

Microcontroller action potential generator

Scott Harden writes: Here I demonstrate how to use a single microcontroller pin to generate action-potential-like waveforms. The output is similar my fully analog action potential generator circuit, but the waveform here is created in an entirely different way. A microcontroller is at the core of this project and determines when to fire action potentials. […]

How to: STM32F103C8T6 as an USB device (Virtual serial port / CDC)

In this video Hugatry shared detailed instructions of how to use the STM32F103C8T6 as an USB device with virtual serial port: Cheap STM32F103C8T6 development board Blue STM32F103C8T6 development boards, also known as “BluePill”, are cheap way to get started with 32bit ARM microcontrollers. The STM32 development board can sometimes be bought for less than $2 […]

Build an open source laser reflection barrier

Boris Landoni from Open Electronics writes about an open source project laser reflection barrier: It allows us to detect the presence and passage of an object thanks to the combination of a laser diode which emits a light ray and a phototransistor which detects reflected light. Robotics applications and industrial control systems normally make use of optical […]

DIY thermal vision shoots 360 panoramas

Saulius Lukse has posted his DIY 360 panoramas: It might seem simple task but it involves some tricks to control motors and read sensor data from two separate controllers. One of the challenges I faced is meshing position and temperature data. Feedback received from each controllers is timestamped. After scan is complete timings are being analyzed […]

Dumb thermometer gets digital output

Saulius has finished a new project article, a dumb thermometer gets digital output: Some time ago I purchased 4 channel thermometer. Soon after tried few optical character recognition (OCR) techniques on 7 segment symbols including pytesseract, they worked but I was not happy with results. Few days ago pyimagesearch published article detailing his approach. So […]

Ultrasonic Transducers – measurements and horn design

Lindsay Wilson writes: Over the past few years, I keep getting inquiries from people asking about how to measure the resonant frequency of these transducers, how to design horns, tune the length etc. I decided it was time to do a video about the entire process – hopefully I’ve covered everything relevant. If you check […]

Programming an 8 digit 7-segment display, the easy way, using a Max7219

Allan Schwartz shows off the easy way to interface 7-segment displays using the MAX7219: Previously, in part 1 of my blog posting Programming a 7-segment Display, using just Arduino digital pins (the hard way) we had demonstrated how to hook up a pair of 7-segment displays to an Arduino, treating each individual segment as a […]

Radioactivity detection using very simple ionization chamber and a single J-FET transistor

Robert Gawron writes: Today I will show a very simple ionization chamber that can detect radioactivity. I was able to detect with it ionizing radiation from a smoke detector (Am241 isotope). It’s also immune to electromagnetic interference (EMI) due to a good shielding. This device doesn’t explicitly use any power supply. It’s connected to a […]