Why is there a lower limit with LOIT_SPEED and WPNAV_SPEED

Why is the lower limit for WPNAV_SPEED 10cm/s and for LOIT_SPEED 20cm/s? Why the difference? AND why is there a lower limit in the first place? Is there a way to circumnavigate those limits, because i need to go slower in a mission.

I currently use the MissionPlanner simulation to test this. Version 1.3.82 with Arducopter 4.5.7-beta1
I use the default copter.param parameter list.

Lower their values below the limit. Do they get ignored?

There is not a lower limit. However, there is an Options range that can be ignored…

Loiter speed
WP speed

Yes they get ignored. As soon as I start the mission the parameter are reset to 10cm/s and 20cm/s respectively.

WPNAV_SPEED is indeed constrained to a lower limit of 10 cm/s.

I’m not sure there is a practical reason for a firmware change to allow slower than a crawl, but that is the line to edit if you really want to go painfully slow.

Realize there may actually be a practical reason that the limit is there. We don’t typically constrain values without some logical reason (and often allow parameter values to exceed the limits displayed in Mission Planner). It’s just a guess, but it may be that the nav controller performs poorly at very slow speed.

I don’t see a similar lower limit for LOIT_SPEED, but I didn’t look very hard for it. The parameter value remains at 5 in SITL when I set it (v4.5.6).

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