Distance Sensor

The HC-SR04 Ultrasonic Distance Sensor is a low-cost module you can use to measure distance. It  "provides 2cm to 400cm of non-contact measurement functionality with a ranging accuracy that can reach up to 3mm"

Review: 

• Ultrasonic Sensor HC-SR04 with Arduino Tutorial

• Sparkfun "Circuit 3B: Distance Sensor"

Operation:

• Send a 10 μ sec pulse to the Trigger input

• Use the "PulseIn" function on the Echo pin to measure the time for the pulse to return to the sensor.

• Calculate the distance

HC-SR04 Ultrasonic Distance Sensor

(2) jumper wires

breadboard

Grove cable

Insert the HC-SR04 Ultrasonic Distance Sensor into the breadboard

Make a Grove-to-breadboard cable:

• Cut a Grove cable in half

• Method 1:

  • Cut (2) different color jumper wires in half to create (4) half-jumper wires

  • Solder the (4) half-jumper wires to each of the Grove cable wires. Insulate the connections with heat-shrink tubing or electrical tape

• Method 2: (this photo  ➡)

  • • Connect male Dupont pins to the cut wires on one half of the Grove cable. 

• Method 3:

  • Purchase a Grove - 4 pin Male Jumper to Grove 4 pin Conversion Cable

Connect the Grove cable to the D7 socket

Connect the jumper wires to the HC-SR04 Ultrasonic Distance Sensor:

• VCC VCC

• GND GND

• D8 Trig

• D7 Echo

Build this sketch ➡

Or, to save some time, click to download this file and save it to your computer (remember where you saved it!)
Ultrasonic_Distance_Sensor_HCSR04.cdc
Then, in Codecraft, use "Files ... Open local projects" to open the file you saved.

Upload and test:

• Move your hand in front of the sensor and look at the distance numbers displayed on the Serial Monitor.

• Do the numbers match the distance between your hand and the sensor (in cm.)?