Many of our customers use Raspberry Pi and other micro-controllers when testing or developing their ideas.  

If you've never tried using our sensors before, it may seem overwhelming, this guide and the others listed below will help you get started with our easy to use ultrasonic range finders. 

If you need help finding the right sensor feel free to click the button "Get Help Finding the Right Sensor for Your Raspberry Pi Project" and answer 10 quick questions, so we can help you get started. 


This article and code example may not work with the most recent versions of the Raspberry Pi operating system.  You may be required to make updates to the code for the sensor to work.   

Do you enjoy or love testing new Raspberry Pi Projects? Maxbotix has put together a tutorial that teaches you how to interface a Raspberry Pi with an ultrasonic sensor to read TTL serial data. You may also want to check out our tutorials on Using an ultrasonic sensor with a Raspberry Pi and how to use USB sensors for a Raspberry Pi.


Getting Started

The Raspberry Pi needs to install an operating system the first time it is used. This article was created for the Raspberry Pi 3 using the Raspbian Jessie operating system (downloaded on 10/06/16). This article was also successfully tested on the Raspberry Pi 2 with the same operating system. This article will be periodically updated as the operating systems, files, and settings are updated and moved.



Key Takeaways

raspberry pi ultrasonic sensors

TIP For the safety of the electronics on the Raspberry Pi and MaxBotix ultrasonic sensors, please use an ESD strap when working around components. Static discharge could damage components of the Raspberry Pi as well as the ultrasonic sensors.


Required Equipment

  • Raspberry Pi with an operating system
  • Ultrasonic sensors with a serial output
  • Mini-Grabbers
  • Male to female jumpers
  • Serial inverter (only for ultrasonic sensors that require an inverter)
  • DC power supply (only for ultrasonic sensors that need a separate power supply)
  • ESD strap


Directly Compatible Ultrasonic Sensors


The Sensors listed below provide TTL serial data and directly interface with
the Raspberry Pi.

Ultrasonic Sensors that Require an Inverter

The Sensors listed below require an inverter to operate with the Raspberry Pi.

Important: Connect the center square with the outer portion of the pad with a small amount of solder to enable the TTL output on the MB1003 from the HRLV-MaxSonar-EZ line.

Ultrasonic Sensor - Solder before
Before

Ultrasonic Sensor - Solder after
After


Enable Serial Data on ttyAMA0

We want to enable the RX pin on ttyAMA0 to receive asynchronous serial data. To allow this, we need to change the set the enable UART setting in the configurations files.

Open the file /boot/config.txt by using the following command:

sudo nano /boot/config.txt

Scroll to the end of the file and add the following lines to the file. Scroll to the end of the file and add the following lines to the file.

enable_uart=1
dtoverlay=pi3-disable-bt
dtoverlay=pi3-miniuart-bt

This will disable Bluetooth on the Raspberry Pi 3 and allow serial communication in its place. While this isn’t fully needed for other versions of the Raspberry Pi, it will not impact their performance.

Save and close the file by simultaneously pressing Ctrl and X to exit the screen and then pressing Y to save it.


Optional: Download a Python Script

This is optional, but you may wish to write or download a Python Script to log and store the data you collect with your ultrasonic sensor.

Here is sample python code provided by one of our users to automate the reading of distance values.


Supplying Power to the Sensor

When using an XL-MaxSonar or WR ultrasonic sensor with a Raspberry Pi, it is highly recommended to use an external power supply. The Raspberry Pi is not intended to supply a high enough current draw to power these ultrasonic sensors.

Ultrasonic sensors from the LV-MaxSonarLV-ProxSonarHRLV-MaxSonar, and ParkSonar lines can be directly powered by the Raspberry Pi.

TIP You may want to place a capacitor between the power and ground lines immediately before the ultrasonic sensor’s pinout. During the ultrasonic sensor’s transmit, the sensor draws a higher current for a fraction of a second. The higher current draw may cause the Raspberry Pi’s microcontroller to begin to shut down. To prevent any issue with long term use, we recommend that you use a capacitor with at least a one microfarad rating to ease the current draw from the Raspberry Pi.


Wiring Instructions

Raspberry Pi 2 wiring diagram

Connect the female end of a jumper to pin 10 of the Raspberry Pi GPIO. This is the RX pin for serial data.

Connect a Mini-Grabber or solder a wire into pin 5 of the sensor, and connect this to the jumper.

Connect your sensor to an appropriate power supply.

Raspberry Pi Pins


Installing Terminal Software

The recommended software for accessing the range data output is Minicom. Please use the following steps to install Minicom.

  1. Open LXTerminal
  2. Download Minicom with the following command
sudo apt‑get install minicom

This will install the Minicom software that is used for reading the serial port.


Accessing Ultrasonic Sensor Range Data Output

Minicom is the recommended terminal software for Raspbian Jessie operating system. Please use the steps below to access Minicom and read the range data.

  1. Open LXTerminal
  2. Open Minicom with the following command

(For Raspberry Pi 3)

minicom -b 9600 -o -D /dev/ttyS0

(For Raspberry Pi 2)
Click Here to learn how to use USB ultrasonic sensors for a Raspberry Pi.

minicom -b 9600 -o -D /dev/ttyAMA0

This clears the LXTerminal window and you will see a window that looks similar to the image below.

Raspberry Pi 2 wiring diagram

The number following the ASCII character is the range reading that is output by the ultrasonic sensor. If the readout says R0764, like the image above, the range to the target is 764mm. As the target gets further away from the ultrasonic sensor, the reported range will increase. If no target is detectable, the target will report maximum range.


Other Raspberry Pi Resources

Connect a Raspberry Pi Zero with an USB Ultrasonic Sensor
How to Set Up Raspberry Pi Zero for an I2C Sensor

How It Works

Request Tech Support

1. Discuss your application with our support team

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2. Choose a Sensor

3. Easily integrate the sensor in your application


Thousands of applications supported 

  • We test our sensors for over 200,000 hours to verify reliability (MTBF)
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We've helped over 20,000 engineers find sensor solutions for their applications.

Our sensors have been integrated into over 10,000 projects.



Collaborators

Our collaborators serve as case studies to show you how the sensors are being used in an end user application.  You can either leverage our Collaborators end product or work with us to find the right sensor for your solution.

Long-range wireless IoT sensor designer and manufacturer

Radio Bridge Inc. provides a general purpose LoRaWAN bridge using MaxBotix sensors to be used in many applications. 


Summary:

  • Industries served: retail, industrial, oil and gas, deduction, utilities, security
  • Typically used in tank monitoring applications
  • Wireless connectivity with LoRaWAN protocol 
  • Wireless penetration through structures such as walls and floors

Ultrasonic Distance Sensor for Tank Level Measurement

LX Group developed an Ultrasonic Distance Sensor for Tank Level Measurement


Summary:

  • Used in grain silos, water tanks, and dams
  • Monitor the level of water tanks remotely
  • The plug-and-play product works out of the box and is robustly designed to work in rough environments.

LoRaWAN IoT Distance Sensor 

Sweden based company ELSYS uses a sensor from our WR line in their IoT Distance Sensor.


Real world applications include:

  • Underground water level measurement

  • Waste level measurement in containers

  • Snow depth measurement 

ABOUT US

MaxBotix Inc. designs and manufactures ultrasonic sensors for use in level, proximity, and distance sensing. 

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