Tag Archives: ATtiny


A very simple posture sensor for your chair

If your job involves sitting in front of a computer for long hours everyday, a poor posture might result in neck, shoulder, and back pain. Sitting up straight helps to get rid of some of these problems. This ATtiny85 based posture sensor uses the HC-SR04 ultrasonic ranging module to sense the position of your head while you are sitting on a chair, and generates an acoustic alarm if you are not sitting up straight.

Ultrasonic posture sensor

Ultrasonic posture sensor

[via]

Chirp: An open source plant watering alarm using Attiny44A

Your favorite plants need plenty of water to grow. If you keep forgetting to water your house plants you might be interested in this plant watering alarm device called Chirp. Chirp uses capacitive humidity sensing technique to measure the moisture level in the soil and alerts the user through short chirps when it is time to water the plant. Based on the amount of ambient light detected by the on-board light sensor, Chirp detects day and night condition. It is very considerate and remains silent during the night time. The project uses ATtiny44A and is licensed under CERN Open Hardware Licence v.1.1.

Chirp: Plant watering alarm