Stereo camera, preprocessing, transforms and frames = pointcloud? [closed]

asked 2017-03-15 05:16:51 -0600

TBnor gravatar image


I am trying to avoid the simple questions, so trust me; I've really tried to figure out this for myself. But I find this to be am beyond my understanding.

Situation - I am acquiring BGR-preprocessed stereo view, but this has raised some issues for me. While the camera software is aimed towards Igloo (and Jade's?) "uvc-camera".

For concretizing purposes, let's assume the simplest version of "differential wheeled robot"; with a base footprint, base link etc - as frequently addressed in tutorials.

My goal is to achieve perception of the environment utilizing as much as possible from generic packages,.,

The camera is published under the /stereo/ namespace 1) How do you describe a stereo camera through xacro/urdf? - Is the camera "one"; with e.g. "optical frame" as origin? Or should the left and right camera be described in a separate manner? - Which frames/transforms am I advised to implement? - Should I utilize a dedicated driver?

2) I am finding a recurring error-messages relating to the packages expecting a colored image. At the same time I am facing all these other challenges, making it impossible for me to deduce whether this is a cause or a consequence.' - I have implemented stereo_image_proc ; but without these issues addressed I find it natural that I don't get any disparity or pointcloud data.

3) If colored images are required; could it be an idea to process the BGR-frames captured; use OpenCV to create a colored image intensifying parameters of interest, and then feeding these to the stereo-vision algorithms at a lower framefrate? (I have managed to utilize the BGR images for cv-processing by using a "cv_bridge"-node).

4) Related to the abovementioned; how do I successfully propagate odometry / pose in a simple conceptual system, where an ekf-node provdes filtered sensordata? I'm assuming I should remap the topic somewhere, but I'm struggling to catch the essential factor here.

5) In general as with the camera; I'm struggling with the countless possibilities relating to frames, tf's and dedicated drivers. Should I use a kobuki or a differential driver? What are the main pro's and con's? (It should be mentioned that I won't receive my wheel encoders before the end of next week, so for now I will have to estimate odometry. )

I hope I'm not completely off track here, thanks in advance. Please notify me if I should change and/or elaborate on any of these issues.

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Closed for the following reason Question does not follow our guidelines for questions. Please see: for more details. by NEngelhard
close date 2017-03-15 13:37:31.353346


Hello! Could you please only ask only one question per thread? (It's perfectly fine to create several questions right after each other) This way, the answers are also more likely to help other if they search for it.

NEngelhard gravatar image NEngelhard  ( 2017-03-15 13:37:16 -0600 )edit

Yes! I will do just that, as soon as possible, feel free to close/delete this one. I've worked ~10 hours since then and talked to the distributor; clarified a whole lot.

TBnor gravatar image TBnor  ( 2017-03-16 04:18:30 -0600 )edit