sonar reading problem

Hi Everyone:

    I use a MB 1200 sonar for my arducopter. I test the sonar in CLI mode. But I observed that the sonar reading is always around 608cm when I put the arducopter on the table. After that I detach the sonar from the arducopter but maintain the three wires conneted to the imu shield. I move the sonar only around and the reading did not change much, 1cm at most.

   I enabled the sonar in CLI mode. What is the problem? Can anyone help? Thanks



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  • If you did not already double- / triple-check that you connected to the correct pins on APM and sonar sensor, then this might be a good idea.

  • Developer


        A good first step re your sonar reading problem is to check the voltage coming out of the sonar's an pin (pin3? with a volt meter.  This way you can check if it's an issue with your sonar or the APM/software.  So if the volt meter reading moves in a reasonable way as you change the distance between the sonar and objects in front of it, then you know the sonar itself is ok.  if it doesn't then you've got a broken sonar.

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