How to keep a sensor pointed downward

Question

I am using LIDAR to measure a robot's altitude. The robot's orientation relative to the ground is dynamic; i.e. the XY plane tilts relative to the Z axis. I would like the LIDAR to remain pointed close to perfectly downward as the robot tilts.

Some details: the tilts can be large, up to 30 degrees, but are short lived; the robot largely corrects its orientation within a few seconds.

Note, I have considered measuring the robots angle to trigonometrically derive altitude. I have also considered barometric pressure altimeters, but those do not have the reaction time I need.

Apologies if anything here was unclear, thank you.

Answer 1

To keep your lidar pointing downwards either:

• mount the LIDAR differently to staticly fix the orientation.
• mount the LIDAR on a gimble to let Gravitation forces point it down.