3D Scanner HAT for Raspberry Pi

From Jonathan Cohen on Tindie:

3D Scanner HAT for Raspberry Pi

3D Scanner HAT expansion board interface for Raspberry Pi running FreeLSS on the PICLOP ATLAS FreeLSS


I wanted to make a custom interface for use with the open-source 3D Scanning software, FreeLSS. I was very impressed with the Arduino-based Ciclop scanner and the Raspberry Pi-based Atlas Scanner. Several FreeLSS users merged the two scanner platforms, creating the PiCLOP 3D Scanner. However, there were few changes to the basic PCB design used for the scanner. I wanted to integrate the hardware functionality into a Raspberry Pi HAT format, with the inclusion of extra features for expandability — and who knows, other uses !


What makes it special?

  • Conforms to the Pi Foundation specification for HATs !
  • 5V power design (only a single voltage) allowing for Pololu low-voltage stepper driver carrier.
  • Connections for up to two independent soft-PWM controlled LED light sources.
  • I2C interface for OLED displays and light intensity sensors, e.g. TSL2561 or TSL2591.
  • Serial communication breakout for console support.
  • Additional GPIO signal breakouts for other sensors and devices.
  • User-programmable EEPROM ! for auto-configuration and device overlays.
  • Standard DC power connector for up to 5V 4A power supply and connections for power switch.
  • Over-current protection by poly re-settable fuse.
3D Scanner HAT for Raspberry Pi

Asset Tracker

Kris Winer designed this is a small 4-layer PCB for remote logging of absolute position and orientation:


Asset Tracker

STM32L433-based board with CAM M8Q concurrent GNSS, EM7180 + MPU9250 + MS5637 for absolute orientation, and an ESP8285 for wifi connectivity.

The absolute orientation engine uses the MPU9250 accel/gyro/magnetometer IMU sensor plus the MS5637 barometer as slaves to an EM7180 motion co-processor that sends quaternions and drift-stabilized altitude to the host via I2C.

PeskyProducts has shared the board on OSH Park:



Order from OSH Park

Asset Tracker

STM32L4 Sensor Tile

From Kris Winer on Hackaday.io:


STM32L4 Sensor Tile

Small, connected device for smelling and hearing in any environment.

This is a 20 mm x 20 mm four-layer pcb tile full of interesting sensors (ICS43434 I2S Digital Microphone, MPU6500 acclerometer/gyro, BME280 pressure/temperature/humidity, and CCS811 air quality) with a Rigado BMD-350 UART BLE bridge for sending data to a smart phone all managed by a STM32L432 host MCU.

The STM32L432 is programmed using the Arduino IDE via the USB connector and serial data can be displayed on the serial monitor to verify performance and proper function, etc. But it is intended to be powered by a small 150 mAH LiPo battery for wireless sensing applications. The STM32L4 is a very low power MCU and with proper sensor and radio management it is possible to get the average power usage down to the ~100uA level, meaning a 150 mAH LiPo battery can run the device for two months on a charge.

A library for it is available on GitHub:


A collection of sketches to run the STM32L432-based (20 mm x 20 mm) sensor tile with an MPU6500 accel/gyro, ICS43434 I2S digital microphone, BME280 temperature/pressure/humidity sensor, and CCS811 air quality sensor. The sensor tile has an on-board MAX1555 LiPo battery charger, an on/off switch, and a Rigado BMD-350 nRF52 BLE module.




STM32L4 Sensor Tile

Automated Pool Controller

Jerad Jacob designed this board to monitor and control a swimming pool:



Cloud-based pump speed, solar collector controls, and temperature monitoring for your pool with SmartThings and Alexa integration

Timer Control of a Hayward Tristar VS Pump and Hayward GL-235 Solar Pool Controller


osmosis has shared the project on OSH Park:

Pool Controller v2.2

Order from OSH Park

Automated Pool Controller

Tindie Seller Interview: Alex Albino

interviewed Alex Albino of Femtoduino for the Tindie blog:

Alex Albino, of the Femtoduino Store, is one of the original sellers on Tindie, with his store officially listed as opening on November 26, 2012. During this time, he’s sold well over 300 of his custom boards, and I was glad to catch up to him to ask a few questions.

Albino, who works as a software and web developer, first got into electronics after his NES was fried in a thunderstorm in junior high, and he got to take it apart. Eventually his interests led him to the Arduino and Fabio Varesano’s work, and multiple hardware platforms over the years.

Albino’s store started with him asking Fabio Varesano if he could sell Femtoduino boards, which have the same outputs as an Arduino Uno in the size of one’s thumb. Since Varesano wasn’t interested in selling them himself, he generously gave Albino permission to run with this design. Albino then went to work assembling and selling these boards, and even made sure to give a portion of the money he made—though he didn’t have to—back to Varesano to promote his open source work.


Of course, these tiny Arduino clones are still for sale, but Albino sells several other items, including the FemtoBeacon wireless IMU (inertial measurement unit) sensor. He even notes his store theme as providing the smallest open source IMU sensors in the world. You can see one in the image above next to a U.S. dime—quite small indeed. He hopes to grow the Femtobeacon business into a full-time job in the future.

Naturally, Albino has bought from other Tindarians in the past, which he says is always fun. He also notes that, “If you sell anything on Tindie, make sure to package carefully, take decent photos, and include videos of stuff in action!” As such, here’s a video of the tiny Femtoduino in action:

Tindie Seller Interview: Alex Albino

Using Si7006 to read temperature and humidity

From the bitknitting blog:


Using the Si7006 to get temperature and humidity readings

I made a PCB with the Si7006 on it. This post is my bumblings encountered as I successfully got temperature and humidity readings from a Si7006 using the PCB I designed. In summary, the Si7006 is easy to work with. It is relatively easy to solder and very easy to access via I2C […]


The design files and source code are available on GitHub:



Using Si7006 to read temperature and humidity

Biomed Shield for Arduino 101

From Orlando Hoilett of Calvary Engineering on Hackaday.io:


Biomed Shield for Arduino 101

A sweet Arduino shield with a ton of cool sensors for physiological parameters such as heart rate and breathing rate

The features include:

  • Heart Rate Monitoring with the MAX30101
  • Pulse Oximeter with the MAX30101
  • Electrocardiogram, Electromyogram, and Electrooculogram with our Super Simple EXG Circuit
  • Bioimpedance with the AD5934
  • Body Temperature with the MLX90614
  • Ambient Light with a CdS Photocell
  • Ambient Temperature with a Thermistor

The design files and source code are available on GitHub:


Biomed Shield for Arduino 101