One way to accomplish this involves four HC-SR04 ultrasonic sensor units that transmit data through an Arduino into a Linux computer. The end result is a virtual touchscreen that can be made at home.

This is an Arduino-based Proximity Sensor circuit wired using the popular HC-SR04 Ultrasonic ranging module,used here for non-contact object detection purpose. The HC-SR04 module includes ultrasonic ...

One way to accomplish this involves four HC-SR04 ultrasonic sensor units that transmit data through an Arduino into a Linux computer. The end result is a virtual touchscreen that can be made at home.