why is there a GRILL in front of the sound-based sensors??? That won't work!

@@dfrobot:disqus hi,
I am using this sensor with Arduino Due and IO Sensor Shield for Arduino Mega Due. (Link: https://www.dfrobot.com/pro...

I am also using the Shield Motor Multimoto. (Link: http://www.robotpower.com/p...

I have connected the DC motor shield to a 12V DC battery.

The sensor gives me the correct value if the battery switch is off. For example, the value is between 14 cm and 15 cm.

However, when I turn the switch on to use the motors, the sensor's value keeps varying (between 9 cm and 21 cm, for example). The switch of the Mega IO Expansion shield is in the position for Arduino Due power.

How can I resolve this problem? I tried putting a capacitor between +5V and GND, but it did not work.

Thank you.

I need to measure the water level inside a tank, will this work? not just an digital measuring, i need several points (analog measurement)
Thanks!

Hi,
It works well actually. Check here https://wiki.dfrobot.com/UR... for more info.