Maxbotix Sonar Comparisons

I moved to maxbotix sensors. The front sensor was a more sensitive (and expensive) model than the side sonars. This is just a place to document the differences.

The EZ0, EZ1 etc describes the beam battern. EZ0 is the widest beam whereas EZ4 is a narrow beam device

HRLV-SonarMax EZ0 (forward facing) sensor

The front-pointing sensor is an HRLV-SonarMax device (black PCB). This is highly accurate (a couple of mm) and has a sensitivity of 1uS per mm. This means the pulse width returned is directly in mm with no conversion factor required. Range is measured from the back of the sensor.

LV-SonarMax EZ0 (side facing) sensors

The side-facing sensor are LV-SonarMax devices (green PCB) and are cheaper than the HRLV sensor. This is less accurate (10mm or so but more than adequate for my needs) and has a sensitivity of 5.787uS per mm. This means the pulse width returned needs dividing by 5.787 to return the distance in mm. Range is measured from the front of the sensor.

Sonar Modes

There are several ways to wire the sensors and I am using them in pulse-width mode. If the Rx pin is held high (or NC), then a stream of pulses are emitted from the PW pin (free run mode). Holding the Rx pin low will stop the sensor ranging. I intend to leave the front-facing sensor in free run mode with the side sonars disabled (due to the wide beam width). The side sonars can be enabled as needed. Only one sonar should be running at any one time in this configuration.

July 2023