I'm having some trouble with to MB1200 sonar on my quad. No matter where it's mounted on the quad or how high/where it's pointed, the only value in the CLI test is 675 cm.
My quad is the stock 3DR built and configured by Udrones (850 motors) running ArduCopter v2.3.
I made sure the box is checked in the Hardware tab to enable and XL-EZ0 is selected as the correct Sonar.
Ran the test in CLI with the sonar mounted to the quad as well as holding it in my hand pointing it at different distances. Made no change to the value displayed.
Attached are the params currently loaded.
Thanks for any help out here :)
Maybe you have a defective unit.
Are you using the sonar for altitude or collision avoidance?
If you are sending out sonar "pings" horizontally, the prop "down wash" is going to screw with your ranging, the faster the air flow across the sonar path, the further away an obstacle will appear.
Same goes for pointing straight down.
Remember you are "stirring up" the medium you are trying to use to transmit your ping pulse.