Ideas for areas to explore

• Finding something fun to measure!
• Seeing if your pet can hear the sensor, some animals can hear ultrasound.
• Checking the maximum range for different objects and the behaviour of the sensor for no reflection ("infinity").
• Checking and explaining the behaviour for very close objects.
• Adding calibration offsets and coefficients to the program based on testing with one or more sensors.
• Determining if sensors can be confused by other sensors operating in the same space.
• Measuring the cone angle for the sensor and exploring physical techniques for reducing this.
• Testing if fast movement affects sensor's ability to measure distance.
• Exploring techniques for enhancing accuracy for stationary objects.
• Checking the behaviour of the standard HC-SR04 at 3.3V.
• Testing the 3.3V tolerant HC-SR04 variants. These may be red and labelled as "1652".
• Explore other similar sensors like the (single transducer) Maxbotix range and ones that use different techniques:
  • SHARP sensors with infrared arrays,
  • STMicroelectronics Time of Flight (ToF) sensors.

Further Reading

• Element 14: The Learning Circuit 85: How Do Ultrasonic Distance Sensors Work? (video)