WPnav perpendicular to the route

hi … I don’t find any documentation on this topic. I’m looking for a solution to make the UAV proceed in “survey” mode perpendicular to the route (therefore rotated 90 degrees to the right or left with respect to the bow) in WPNav. Do you have any info about it? thank you

You may try to adjust WPNAV_RADIUS parameter, as mentioned here:
https://ardupilot.org/copter/docs/common-mavlink-mission-command-messages-mav_cmd.html

With no delay specified the waypoint will be considered complete when the virtual point that the vehicle is chasing reaches the waypoint. This can be 10m (or more) ahead of the vehicle meaning that the vehicle will turn towards the following waypoint long before it actually reaches the current waypoint