Servers by jDrones

What events trigger FS_CRASH_CHECK?

(Dorian) #1


With FS_CRASH_CHECK, what types of events trigger a failsafe?

For example, if the rover steering does not work during an automatic run, is the failsafe activated?

(Khancyr) #2


The crash_check will trigger if the rover should be moving but isn’t . block by a wall, in a hole, to much friction etc…
The implementation is quite simple for now but it working well.
This failsafe will not be trigger it the rover don’t turn when it should. It is an interesting idea for improvement !

(Dorian) #3


Thank you for your answer.

I begin with Rover, I have more experience with Copter.

At the beginning I had searched a feature like “Polygon fence” in copter but, for FS_CRASH_CHECK will be great if it will can work in auto mode when a steering broken.

This would be a big plus for security

(mroberts) #4

Failure to turn would be an interesting trigger - if you have velocity and are at maximum commanded steering but are not achieving your yaw rate one of two things has happened:

  1. Your steering is broken
  2. You are understeering (front wheels have lost traction either from turning too far, braking too hard, or accelerating too much)

Without direct feedback it’s hard to tell which.

You fix understeer by reducing steering input until you regain traction or transferring weight to the front wheels (or reducing throttle in a FWD car).

One option would be to start reducing speed. You will either regain traction and start getting the yaw you need (if you’re understeering), or you’ll eventually stop (which is the best response to broken steering). That logic would be the simplest.