The treat in question is detected by an SR-04 ultrasonic distance sensor connected to an Arduino Nano. All in all this was a highly successful build as far as neighborhood entertainment value goes.

A low-cost (~$100), do-it-yourself (DIY) ultrasonic water level sensor/datalogger has been designed, constructed, and tested for use in education, citizen/community science, and research settings. The ...

The compact module helps us to test HC-SR04 modules quickly without a costly microcontroller setup (no code lines/solder smokes) and/or build an extremely portable minimalistic sonar device. I have ...

Cheap stuff gets our creative juices flowing. Case in point? [Andy Grove] built an eight-sensor HC-SR04 breakout board, because the ultrasonic distance sensors in question are so affordable that a ...