Let's Make Robots!


Maxbotix (with Arduino) LV EZ1 questions


I am having problems with wrong readings from EZ1 and my Arduino. I am using the PWM mode and I have checked all tutorials/samples I found. So my questions would be:

Reverse polarity protection for Maxsonar sensor

Hi guys,

This is an image from the Maxbotix site, a circuit recommended for removing electrical noise. I was wondering whether it is safe to replace the 100ohm resistor with a diode (with a low forward resistance), so that it can double up as a reverse voltage protection element.. ?


Image from Maxbotix


Dual Ultrasonic sensor

For my next "top secret" robot project I need 2 ultrasonic sensors. Playing around with the Maxbotix MaxSonar EZ1, which perfectly matches in size for this task, I stumbled across the following problem.

Audible click coming from Maxbotix LV EZ1

Just got my sparkfun stuff today, and while testing my Maxbotix LV EZ1, I can hear a faint clicking noise a few times a second. Also, the Analog values seem to be completely inaccurate. I think the accuracy may be with the Power supply (ATX computer psu). The clicking noise can only be heard when the sensor is pointed directly at my ear. The sample rate of this sensor is 20Hz, so I know it shouldn't be the sampling device making the noise. Any experience with this strange problem?