Tag Archives: Ultrasonic Sensor

Robotics Training LESSON 18: Obstacle Detection and Collision Avoidance

In this lesson we explore using the HC-SR04 to detect obstacles, and then avoid collisions by stopping the car. This requires a more sophisticated control algorithm for the desired distance for the car to travel. Making it even more tricky, after the obstacle is removed, the car needs to resume its programmed mission. The video shows my solution to this problem

 

Arduino Tutorial 61: Improving Precision of Your Distance Measurements

HC-SR04
HC-SR04 Ultrasonic Sensor in a Distance Measuring Project

In this lesson we strive to improve the precision of our distance measurements using an average of a large number of measurements. This builds on the work we did in the last few lessons.

We are building this with parts from our Elegoo Kit , and our actual build is using an Arduino Nano, which allows the project to be built on a single breadboard. You can get the neat jumper wires HERE.

This video takes you through the process step-by-step.

The code developed in this video is included below for your convenience.

 

Arduino Tutorial 60: Add a Go Button to your Distance Sensor

Ultrasonic Distance Sensor
This is our completed build of a portable, ultrasonic distance sensor.

In this lesson we add a “GO” button to our portable distance measurement system. Note that from the work done in Lesson 59, we are only left with digital pin 13. The problem is that pin 13 is connected to the on-board diode, so trying to use pin 13 as a button pin will not work.

Never fear we can use one of the analog in pins. To use an analog in pin as the button pin, in the void setup, you need to declare the pin as an INPUT, and then digitalWrite the pin to HIGH. This will connect it to 5V through a pullup resistor. Now you just have to do a digital read to that pin. When button is untouched, you will read a “1”, and when you press the button, you will read a “0”.

We are building this with parts from our Elegoo Kit , so if you get this kit, you will be using the same hardware we are using.

A challenge with this project is to keep the build neat and compact, which is much easier if you use an Arduino Nano, which allows the project to be built on a single breadboard. The build neatness is also facilitated by using small straight jumper wires, which you can get HERE.

This video takes you through the explanation step-by-step:

This is the code used in this project:

 

Arduino Tutorial 55: Measuring Distance With HC-SR04 Ultrasonic Sensor

This lesson builds on the work done in Lessons 53 and 55. In this lesson we use the Ultrasonic Sensor to build a distance sensor. The HC-SR04 ultrasonic sensor can be programmed to send out a ping, and then measure the time it takes to hear the echo of the ping come back, after bouncing off a target. Knowing the speed of sound allows us to calculate distance to the sensor.

The circuit uses the following Schematic:

HC-SR04-Schematic
Schematic for Connecting the HC-SR04 to an Arduino

This is the code we develop in the video

The sensor is part of our Elegoo Kit , so if you get this kit, you will be using the same hardware we are using. This project builds on the work we did in Lesson 53.

For this build we will be using an Arduino Nano, which allows the project to be built on a single breadboard. You can use the Arduino Uno if you do not have a Nano, and things will work out the same. The build neatness is also facilitated by using small straight jumper wires, which you can get HERE.