All you generally need is the Arduino IDE, which already includes most of the popular libraries for interfacing with frequently used components like ultrasonic sensors and LCD modules. The ...

Inside [Klaus]’ device is an Arduino Uno, an HC-SR04 ultrasonic distance sensor, and an Adafruit Wave Shield. Originally, this parking/distance sensor used a small TFT to display the distance to ...

The transmitter and receiver For the transmitter, he turned an Arduino ... do with the ultrasonic transducers? You could wire a bunch of them to a Raspberry Pi to make a piano interface.