Sonar Scanner
As part of an ongoing project I sourced a mounting bracket for an HC-SR04 ultrasonic sensor sitting on top of a 9g servo motor that can be used to rotate the sensor through a 180 degree arc. I also wanted to include a DHT11 temperature sensor to help determine a more accurate speed of sound. The final setup will probably be run from an Arduino Nano but before planning that I wanted to run some tests on a handy Uno as that has more power supply pins immediately available. The actual rats nest is shown. Here are how the components are wired up to the Arduino. The DHT11 I have is mounted on a little board that includes a pull-up resister between Vcc and the data pin and in fact only exposes Vcc, Ground and data out pins. This is the most common format around as far as I can see and adds up to a nice package that has reasonable accuracy (within 2C in the range 0C to 50C). I downloaded and installed the DHT library from Adafruit to read the sensor although there are others aro