Can't check drone velocities.

[guiaugustoga987]

Hi,

I need to know the drone velocities in m/s. How do I acess this information ? If I echo /bebop/odom topic I get all twist.twist data = 0 as you can see :

header:
seq: 522
stamp:
secs: 1691184697
nsecs: 428244013
frame_id: "odom"
child_frame_id: "base_link"
pose:
pose:
position:
x: 0.0
y: 0.0
z: 0.0
orientation:
x: -0.0007713166171202364
y: -0.017880132644812745
z: -0.9997898473865937
w: 0.009998349362347272
covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
twist:
twist:
linear:
x: 0.0
y: 0.0
z: -0.0
angular:
x: 0.0
y: 0.0
z: 0.0

On topic /bebop/states/ardrone3/PilotingState/SpeedChanged I get :

---

header:
seq: 868
stamp:
secs: 1691183742
nsecs: 303088109
frame_id: "base_link"
speedX: 0.0
speedY: 0.0
speedZ: 0.0

How do I access these data ?

Thanks.

[guiaugustoga987]

It seems like the values are only published when a takeoff command is send to the drone.

[araujorayza]

I've had a similar problem but no response in #187 . Are you using bebop 2?

[guiaugustoga987]

Yes. As I said, the linear velocities display non-zero values only when the drone is flying. But the angular velocities remain zero anyway.