Perception FAQs

How many typer of sensors calibrations are present?

There are 5 types of calibration:

• Camera - Camera

• Camera - LiDAR

• Radar - Camera

• LiDAR - GNSS

• IMU - Vehicle

For additional information on Sensor Calibration, please refer to our calibration guide

For additional information on LiDAR - GNSS calibration please refer to our LiDAR - GNSS calibration guide

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Is the order of sensor calibration important at all ? Can I do IMU - vehicle before Radar - Camera ?

Yes it is important, but you could calibrate the IMU - Vehicle before Radar - Camera

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Are you going to release the source code for the calibration tools ?

No, we currently have not released the source code for our calibration tools.

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How do you ensure that the right calibration files are loaded for the perception module ?

In each car, specific Camera parameters should be saved and the default parameters will be replaced by the saved parameters when you install the release version. When user select a vehicle, we’ll copy files from calibration/data/[vehicle]/[src_data] to target places. The code is at Link. This action is totally configurable, see the example here

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I am trying to run the extrinsic sensor calibration tools and they seem to complain about the INS_STAT not being 56. But when I echo the /apollo/sensor/gnss/ins_stat topic I can see that the position type is 56. What could be the problem?

The error log occurs (stat=-1) whenever the tool has not received any GNSS message or the image stamp is not correct. Please check the topic of GNSS message or image stamp.

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More Perception FAQs to follow