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5 votes
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Questions regarding 3D scanning and camera choice

My favorite is the Learning OpenCV book. It has a fantastic stereo / 3D section that introduces concepts from the ground up. If you're at a university, you might be able to find the digital version ...
abarry's user avatar
  • 176
4 votes

Kinect v1 VS Kinect v2

Kinect 1 is a structured Light sensor, Kinect 2 is a Time of Flight camera. Structured Light gives you better performance on edges where a ToF camera smoothes the data due to multipath-measurements. ...
FooTheBar's user avatar
  • 1,355
4 votes
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Stereo camera Vs Kinect

The Kinect is certainly a popular choice these days for robotics. However, time-of-flight, structured light, and stereo cameras all have their own strengths and weaknesses. These two threads have a ...
Ben's user avatar
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3 votes
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I am making a Ping pong-playing robot using two cameras to trace the ball (3D vision),what is the minimum Frame rate of the cameras?

The movement of the ping pong ball is going to be ballistic, so you really only need to know its 3d position in 3 different locations in order to fully constrain its motion. In reality, you will ...
Mark Omo's user avatar
  • 1,909
3 votes

RGB-D SLAM - Compute Information Matrix

The information matrix is the inverse of the covariance matrix. In this case, the covariance is over the variables (x,y,z,qx,qy,qz). It is assumed that your quaternion is normalized to be unit ...
DrRoboto's user avatar
  • 181
3 votes

What main factors/features explain the high price of most industrial computer vision hardware?

So the Kinect uses a set of IR points to determine depth, not true stereoscopy. the DUO M and the Bumbee both use two cameras to achieve this, I am not familiar enough with them to give a good ...
Mark Omo's user avatar
  • 1,909
3 votes

ROS and Kinect data without callbacks

You should simply use the callback method since you can have an object in your code that is always updated with the latest measurement. Then you can simply poll the measurement in that object whenever ...
Brian Lynch's user avatar
  • 1,377
3 votes
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Kinect VS Stereo cameras

Kinect: Pro: cheap already calibrated active system (works also on textureless surfaces) dense stereo Con: defined range (low maximal range) does not work good outdoors in direct sunlight Stereo: ...
FooTheBar's user avatar
  • 1,355
3 votes

ROS + SLAM + kinect. which platform to use?

There are several platforms possible, depending on your experience level and needs. If you are comfortable working with the Raspberry Pi or the Beagle Bone... the next step up might be the Jetson TX1 ...
Mepix's user avatar
  • 295
3 votes

Calculate information matrix for graph slam

The information matrix is just the inverse of the covariance matrix. I recommend you read the page I linked, or just google covariance matrix. Essentially it contains how certain you are in your ...
edwinem's user avatar
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2 votes

What main factors/features explain the high price of most industrial computer vision hardware?

As Mark Omo mentioned, the Kinect is a fundamentally different technology than a simple stereo pair. There are also other technologies such as a "standard" time-of-flight cameras like the Swiss ...
Ben's user avatar
  • 5,780
2 votes

ROS and Kinect data without callbacks

Until you learn more about ROS the best approach is to use a callback. You can copy the data to a global variable and use that in your main program if it helps you reason about the data flow better. ...
hauptmech's user avatar
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2 votes
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Using an RGB + Depth Camera to locate X,Y,Z coordinates of a ball

The critical part is the registration between depth data and RGB data. If the registration is calibrated properly then you can just extract the depth for the particular target pixel (X,Y), using ...
Brian Lynch's user avatar
  • 1,377
2 votes

Is there an algorithm using the Kinect depth image (not the point cloud) for registration?

Consider this - what is the process of doing SLAM? First, get some sensor data, then move in the world, get some more sensor data, then try to do feature identification and matching to build up a map. ...
Chuck's user avatar
  • 15.9k
2 votes

Calculating the distance of a point from point cloud data

These values are relative to the camera. Z is always positive as the camera can't see what is behind. X and Y can be positive or negative depending on if an object is left/right or higher/lower than ...
FooTheBar's user avatar
  • 1,355
1 vote

I am making a Ping pong-playing robot using two cameras to trace the ball (3D vision),what is the minimum Frame rate of the cameras?

First you need to calculate the maximum processing period time you can accept, preferably use (motor response time)/5 or less to be sure that the motors move smoothly .. also you need to calculate ...
Ghadeer Elmkaiel's user avatar
1 vote

How to compute the field of view of a robot when obstacles are around?

Yes, you "simply" geometrically substract those objects and everything behind them from your FoV. But it make not much sense to create such formula, as its precise formulation would be dependent on ...
gilhad's user avatar
  • 453
1 vote

How to implement RANSAC and kalman filter or particle filter algorithms with ROS packages?

Like with anything in engineering, you first need a good definition of what "success" (or "done") means. SLAM running how fast? Under what particular lighting and environmental conditions? Using what ...
Jon Watte's user avatar
  • 720
1 vote

ROS + kinect depth data duplication

I hope I am understanding your issue right. The "complex" error looks like an encoding issue: depth data does not contain any complex numbers. Try removing the CV_32FC1, let it fallback to "...
HighVoltage's user avatar
  • 1,086
1 vote
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Modelling Point Clouds for Collision Detection in Gazebo

For the most part I was able to get this done. The only difference I chose was to use the Point Cloud library's triangular mesh generator instead of Meshlab's mesh generator mainly because Meshlab's ...
Iche's user avatar
  • 304
1 vote

Using an RGB + Depth Camera to locate X,Y,Z coordinates of a ball

Very common problem which calls for using the "Pointcloud Library" PCL: www.pointclouds.org This datastructures in the library also make it easy to find according 3D-Points when you segmented your RGB ...
Squelsh's user avatar
  • 134
1 vote

How to efficiently do 3D mapping of an area on a MAV?

In your case I would suggest using the stereo version because: - You already said Kinect is technically not a possible solution because of the sun's IR light - A reasonable good lidar sensors costs a ...
TobiasK's user avatar
  • 1,657
1 vote

Troubleshooting Xbox Kinect 360

Well, from the last post in the thread you linked states it's a USB speed issue, then says you need 20 MB/s to do depth and RGB, which means you cannot do it on a USB 1.0 port; you need 2.0 or 3.0. ...
Chuck's user avatar
  • 15.9k
1 vote

Do structured light camera sensors work outdoors?

I only have experience with the kinect, but it will definitely not work outside no matter what (unless the sun is down) and I have had problems when giving demos near large windows with sun. Tldr ...
Mark Omo's user avatar
  • 1,909
1 vote

Depth image sensor for integration into robot

If you want a low cost vision sensor that does all the work for you I sugest you look here -> Pixy Cam From here you can work with two cameras and build your application using stereo vision to ...
Jónatas Brás's user avatar
1 vote

Depth image sensor for integration into robot

What kind of processing power are you hoping to carry to do the depth sensing/processing? I would recommend the ZED camera when paired with an Nvidia K1 it works great for mobile vision processing, it ...
Mark Omo's user avatar
  • 1,909
1 vote

Questions regarding 3D scanning and camera choice

PCL library has all the functionality you need for 3D scanning, as well as it have the complete GPU pipeline, take a look at kinfu. Here is some tutorial regarding 3D scanning. Take a look at MeshLab ...
DikobrAz's user avatar
  • 241
1 vote

What main factors/features explain the high price of most industrial computer vision hardware?

As others mentioned the Kinect is a different technology which has different trade offs. Stereo performs better in sunlight than a Kinect and it is easier to adapt the range, particularly if longer ...
DrRoboto's user avatar
  • 181
1 vote

RGB-D SLAM - Compute Information Matrix

Your sensor does not measure state Kinect does not provide any "measurements" of state. It scans the environment and provides a point cloud. To use this to localize a robot, you must compare ...
Josh Vander Hook's user avatar

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