Long Range Sensing

Key Takeaways

• MaxBotix^® Inc., limits its maximum detection range to 10 meters (32.8 feet)
• MaxSonar^® sensors offer reliable people detection out to ~5.4 meters (~18 feet)
• Targets must be perpendicular or able to reflect sound back to the sensor for long range detection
• MaxBotix^® Inc., presses the limits by pursuing new technologies

Ten Meter Ranging

MaxSonar^® sensors have are used in a variety of applications. Many customers have successfully used our sensors at ranges up to 10 meters. While not every sensor we produce will range out to 10 meters, many of our product lines do contain long range sensors with 10 meter ranging capabilities. Even though a sensor provides 10 meter ranging, there are some limitations that will disqualify our long range sensors for use in some applications.

MaxSonar^® sensors utilize ultrasonic sound waves to create the sound burst. The sound waves dissipate as they flow through the air. If they do not return to the sensor, then the sensor is unable to calculate the distance to the target.

Target detection beyond 10 meters requires that the sound waves return with enough amplitude for the sensor to correctly process the sound data. Typically, only large flat targets that are perfectly aligned to the sensor can produce such a reflection. This is very possible, in a lab environment, however, this is not practical outside of a controlled lab setup.

Additionally, the angle of incidence or the angle at which the sound waves hit the target will also affect long range detection. If the target object is not completely perpendicular to the sensor, the sound waves can miss the sensor on the bounce back from the target. The further back the sensor is placed from the target, the more precisely perpendicular the sensor must be to the target. As longer ranges require such a high degree of precision in the mounting of the sensor, we have capped our long range sensors at 10 meters.

Ten Meter Ranging

One common request is for long range people detection. We have recommend two main sensors for this task: the MB7363 HRXL‑MaxSonar^®‑WRLS and MB1260 XL‑MaxSonar^®‑EZL0. When reviewing the beam pattern of the MB7363 a person falls between graphs A and B which offers approximately 5.4 meters (18 feet) to reliably detect a person inside of the beam pattern. For greater detection, our MB7974 Snap-On Horn amplifies the detection abilities of the MB7363 for slightly greater sensitivity which helps to slightly extend the range of people detection.

The MB1260 shows a wide beam pattern with a detection range of approximately 4.8 meters (16 feet). MaxBotix^® Inc., continues to press the limits of our sensor technology by continually pursuing technological advances to provide reliable range detection beyond 10 meters. We welcome customer feedback and questions on our long range sensors.