About the problem“Bad Lidar Health”

hi all,I am using LiddarOne to achieve a stable landing on the 3.4.6 version of the firmware, and my settings follow the official designation parameters (http://ardupilot.org/copter/docs/common-leddar-one-lidar.html ): SERIAL4_PROTOCOL = 9 (Lidar)
SERIAL4_BAUD = 115200
RNGFND_TYPE = 12 (LeddarOne)
RNGFND_MAX_CM = 4000 (40m)
I encountered the following two questions:
1 - when I fly the plane from the ground from 0 to 50 meters in the process, the aircraft in about 25 meters MP error “Bad Lidar Health”, while the height continues to rise when the sonar height has been equal to 25 meters (take off when no error and Sonar height curve is correct); when I began to drop from 50 meters to reach the 13 meters or so, the error was canceled, and the height curve returned to normal;
2 - when I was on the ground (loiterORalthold), it was clear that liddarone had a good effect; but when the automatic landing was done, the effect of the effect was not significantly improved with the barometer, and at 10 m Before I saw the plane had 2-4 times the speed from the fast to slow pause landing; I do not know why

I am a forum novice, Request for help

Hi, sorry nobody answer till now.
I hope you have fix your problem since firmware 3.5 works fine, at least when the sensor looking down. The problem comes when you want to avoid object from high and then get the message bad lidar health