MaxBotix Ultrasonic Rangefinders

By Robert Cong

When it comes to enhancing the design of your robot, there are many types of sensors that are available, but the most important one may be the ultrasonic sensor. The most precise ultrasonic sensors will be needed and those come from MaxBotix Inc.

While some sensors use light waves such as infrared, ultrasonic sensors pose an advantage by using sound waves, enabling better detection of clear objects, objects on uneven surfaces, and even liquids. Typical ultrasonic sensors like the PING))) utilize one transmitter to send the sound wave at a very high frequency and one receiver to detect the echo that bounces back from an object.

MB1040 Ultrasonic Sensor
MaxBotix MB1040 Ultrasonic Sensor
(21-foot Detection Range)

MaxBotix ultrasonic sensors use one transceiver to perform both functions, giving the sensor the ability to take up less space and be more discrete.

Wave Diagram
Typical Sensor Using a Transmitter and Receiver

There are a few different models of ultrasonic sensors available from MaxBotix. The original ultrasonic range-finding LV-MaxSonar-EZ Line measures less than 1 square inch in size. The XL-MaxSonar-EZ Line has greater sensitivity and greater noise tolerance. The industrial outdoor ultrasonic XL-MaxSonar-WR Line has robust PVC housing designed to meet IP67 water intrusion

All lines of sensors essentially do the same job, but exactly which model is right for you depends on your project's application, target size, and distance to be detected. Most operate from 3.0V to 5.5V, so it's easy to integrate with low voltage microcontrollers like the Arduino.

LV-MaxSonar®-EZ™ & XL-MaxSonar®-EZ™ Sensor Lines

Product No. Overview
MB1000 Widest and most sensitive beam pattern. An excellent low cost choice for use where high sensitivity, wide beam, or people detection is desired.
MB1010 Most popular indoor ultrasonic sensor. A great choice for use where sensitivity is needed along with side object rejection.
MB1040 The narrowest beam width sensor that is also the least sensitive to side objects. An excellent choice when only larger objects need to be detected.
MB1210 Offers a lower hardware gain and a smaller, narrower detection zone. A great choice for people detection applications.
MB1240 The highest noise tolerance and narrowest beam of any of our indoor sensors. Designed to provide reliable range information to large targets even in environments with noise sources.

XL-MaxSonar®-WR™ Sensor Line

Beam patterns for each sensor are displayed on each product datasheet. Beam patterns provide information on approximate target sizes and distances so you can identify the optimal application for your robot and choose the appropriate sensor.

Beam Pattern
Beam Pattern for the MaxBotix MB1000

Ulttrasonic sensors can be used in a variety of ways, from detecting and avoiding objects to measuring precise distances. People (and animal) detection is also a possibility, though it may not be as accurate, as living things have different reflective properties compared to hard surfaces (sound is mostly absorbed) since ultrasonic sensors do not rely on mechanical operation, they are less prone to wear and tear and possess a very high MTBF. Best of all, ultrasonic sensors add a cool feature that can be integrated with any of your existing designs.

Robert is a graduate from Cal Poly, San Luis Obispo in Electrical Engineering. His interests include sports, movies, music, and playing with cool, new gadgets.

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