Copter: vehicle twitches when do-change-speed command is executed

[liang-tang]

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Bug report

Issue details
comment line

copter.wp_nav->set_fast_waypoint(true);

and WPNAV_SPEED set to 500cm/s, DO_CHANGE_SPEED set to 1m/s， when implement DO_CHANGE_SPEED，vehicle got a shock。

Version
3.6.0 rc6
Platform
[ ] All
[ ] AntennaTracker
[ * ] Copter
[ ] Plane
[ ] Rover
[ ] Submarine

Airframe type
What type of airframe (flying wing, glider, hex, Y6, octa etc)

Hardware type
SITL

Logs
2018-08-02 16-28-47.zip

[liang-tang]

[liang-tang]

[liang-tang]

Copter 3.5.7 version test result
speed 5m to 1m.


log here
2018-08-06 10-33-38.zip

[rmackay9]

@liang-tang, thanks for that evidence. The vehicle will need to slow-down to the new speed of course, so it makes sense that it will lean back for a bit. The question is whether that's too rough or not.

What is that a graph of? The pitch angle or is it speed or something else?

[liang-tang]

sorry about the graph, it's pitch angel.

[liang-tang]

All test in SITL, execute LOITER_TURNS command.
Copter 3.5.7

Copter 3.6.0 rc6

WP

[liang-tang]

Copter 3.6.0 rc6
but when test with WAYPOINT command, it never twitch....

WP

[liang-tang]

@lthall any idea about this？

[RickReeser]

Is this the same issue as #8627?

[IamPete1]

closing in favor of #8627