I got an early Christmas present. I bought myself a Lightware LW20 i2c version. I tried to follow the guide at http://ardupilot.org/copter/docs/common-lightware-lw20-lidar.html but the sonar distance is always 0. I have double-checked and triple-checked my settings and everything seems fine. As an experiment, I connected the LW20 to a Raspberry Pi and I enabled the following stream $1,ldf . I can then read from the i2c bus which gives me results like these ldf,0:0.87 for example.
Does anyone else have a LW20 i2c version that works ?