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The devkit of the nuScenes dataset.
https://www.nuScenes.org
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why is the steering angle so big? #1087

Closed nunuisacat closed 4 months ago

nunuisacat commented 5 months ago

Hi, thanks for the nice dataset. I have a question regarding the value interval of steering angle feedback data. Normally the steering angle should be within minus plus 30 Degree, which corresponds to radians [-0,5, +0.5], but why the interval in canbus recording is [-7.7, 6.3]? Did I misunderstand anything? Thanks for the help.

whyekit-motional commented 5 months ago

@nunuisacat pls provide a working code snippet to reproduce your observation

nunuisacat commented 5 months ago

@nunuisacat pls provide a working code snippet to reproduce your observation

Hello, thanks for the kind and in-time reply. Here are the code: ` from nuscenes.can_bus.can_bus_api import NuScenesCanBus from nuscenes.nuscenes import NuScenes

nusc = NuScenes("v1.0-mini", "/data/nuscenes")
nusc_can = NuScenesCanBus(dataroot="/data/nuscenes")

scene_name =nusc.scene[1]["name"]
# get the steer angle feedback from the can bus
saf = nusc_can.get_messages(scene_name, "steeranglefeedback")

# use the bicycle model:  steering_angle/wheelbase = curvature  to calculate the curvature
Kappa = saf[-1]['value'] / 2.588

I aim to use the steering angle to calculate the needed trajectory curvature.
since saf[-1]['value']=3.06 thus Kappa = 3.06/2.588 = 1.18, the turning radius 1/Kappa will be smaller than 1m, which is obvious not possible. Thanks for the help.:)

whyekit-motional commented 4 months ago

@nunuisacat if the driver turns the steering wheel with multiple revolutions (e.g. during a strong left / right turn), then the steering angle would be large