Questions tagged [cameras]
A camera is an optical instrument for recording or capturing images, which may be stored locally, transmitted to another location, or both.
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Determining Orientation of a Robot Relative to a Line on Table
I am currently busy with a robot that needs to obtain it's orientation relative to a line seen by a camera. At the moment, I am using Hough lines to obtain a gradient for the line, but the gradient ...
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Hint regarding Localization & Map Scaling
I just started with mobile robotics. I'm trying to do a collaborative system between a mobile robot and a ceiling camera (Raspberry). They should do all tasks as a "team". Means Calibration, ...
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Intel RealSense Depth Camera D435i Wide Imager questions?
I have just ordered my d435i and while it was not intended to do NDVI I read the data sheet and noticed it had seperate image sensors, it is possible to read the IR image from either left, right or ...
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Use Realsense camera to get the camera image
I have to use LIDAR in my project. I was searching for some LIDARs with a camera and came across the Intel RealSense d400 series. I know it has a camera but please suggest a way to use that camera ...
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Planar Robot Boundary Detection
I am tasked with building a robot that needs to localise and navigate itself on a rectangular surface (like a large desk). The rectangle's shorter sides will be marked with a red tape (or with two ...
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How to derive the camera trajectory from ICP
This may be a very simple question so please bear with me...
Suppose I have a stationary object and point clouds, $n$ $(x,y,z)$ points, of that object taken by a moving camera at time steps $t_i$, $...
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Collaboration of mobile robot and survaillance camera - classic localization (still) needed?
Just started with the topic of mobile robotics..
so I'm still into concept making and little programming, but have not setup everything or tested at all. I got a (differential) mobile robot (lego ...
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Interpreting results from Camera Calibration?
I used OpenCV's findChessboardCorners on a few checkerboard images (40~) and about 27 seemed to find the corners accurately. How does one proceed from here? Do I calculate the reprojection error over ...
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How to plot the 3D camera trajectory from a VSLAM output
I am totally new to VSLAM algorithms and would want to plot the path followed by the moving camera. I am using the open source implementation of ORB_SLAM2 for a rgb-d camera on benchmark dataset. The ...
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Depth images with undetectable outlines
I'm trying to capture depth images with a RGBD camera, but all of the images have undetectable outlines around objects:
Is this expected from RGBD cameras or is mine a dud? It's an Astra Pro.
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Is there a specific way or module I can use to stream video data from a camera hooked to an Arduino Uno board?
I'm currently thinking about the feasibility of creating a robot which streams live video footage and other data such as temperature, humidity, etc. to a smartphone. Is it possible to do this on an ...
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What is the baseline of a RGBD camera?
I'm looking at some ORB SLAM2 settings where there's a parameter for "IR projector baseline times fx". Could someone here explain what exactly is the baseline of an IR projector? Is it the distance ...
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Decrease minimum depth of a RGBD camera
I have a Kinect camera which has a minimum depth of 0.5m and I'm trying to find a way to decrease it to around 0.2m for near-depth detection. Does anyone know how this can be done? Can a macro lens be ...
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How to get a wired live feed from camera to phone
I need a clear video live feed from a camera to an android phone. The connection does not have to be wireless because i have to use it without any internet. The camera and phone will be 2 or 3 meters ...
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What is the relation between FOV, Focal Length and Sensor size in a Pin hole Camera Model?
I aim to recreate the camera parameters of my camera in the Unity rendering system, which has the following variables:
1) I tweaked the focal length and saw that the Field of View is changing (...
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How do I set all objects in my scene to be aligned with respect to the camera in Unity 3D?
To elaborate further - How do I fix the camera as the origin of the 3D world?
The context is I am trying to create some synthetic image data for a robotics project, and I have the coordinates of the ...
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Is it possible to calculate a homography matrix for any 2 views?
I've been experimenting with opencv to estimate the homography matrix between 2 images captured with my computer's webcam. I have noticed that when the 2 views are not very far apart (that's when I ...
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Questions about customized stereo camera
I am designing my robot and I have quite design issues with the available stereo cameras on a market.
For the prototype I am using ZED M but it is too expensive and quite large.
The question is, do ...
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Position vs Image based visual servoing?
Can anyone explain Image based visual servoing for robotic arm through example?
I can understand Position based based visual servoing like this,
....
there is an object and estimating it 6D Pose ...
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RGBD Camera Eye in Hand Calibration
Hello I am new to robotics. So far I have a basic understanding of the camera calibration. One would need rotation and transformation matrices to convert a point from camera coordinate system to robot/...
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vision guided robotic arm always required 6d pose of object? [closed]
I have an object like attached in image.
It is hanging vertical (its position may change but static object) and I want to grasp it using 6DOF Robotic arm. I am Using camera to detect object.
I am ...
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Short range stereo vision
I am designing a stereo vision system for short depth range (15 cm to 35 cm) and I have some problems about baseline, focal length and depth range.
My application is to scan an animal tissue (meat, ...
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Extrinsic calibration of a multicamera-rig mounted rigidly on a mobile robot
We have a set of 8 cameras mounted rigidly on a mobile robot. The cameras are forming an arc, which allows a 360º vision.
I want the extrinsic parameters of them referred to the robot. Is there any ...
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robot Hand Eye Calibration problem
I am trying to understand the implementations and the relative performance of various classical and new Hand-eye calibration approaches.
Note: The following discussion assumes implementations are in ...
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How can I preserve a high framerate while using at least 1280x720 resolution on 2 USB cameras on the same computer?
To expand on this, I have a down-facing camera using the whycon ROS node on Ubuntu 16.04 Kinetic on a quad-core computer with 640x480@60fps MJPG video. I'm also using the ...
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Stereo-Calibration with Variable focal cameras
Is it possible to perform stereo-calibration with cameras having variable focus? and if so, how is it done basically?
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Stereo Rectification when Extrinsics are known
Suppose I have two cameras $C_1$ and $C_2$ arranged in a stereo configuration. Let us assume that the camera is free of distortion with ideal intrinsics and that the camera extrinsics $R$ and $t$ are ...
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hand-eye calibration for wheeled mobile robots
I am new to robotics and working with a wheeled mobile robot with one Kinect mounted on top of it currently.
The robot knows its position in the environment via some means.
I encounter one problem. ...
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Setting up a Structured Light Stereo system
I am trying to get started with a stereo experiment and wanted to know the mistakes I might have made during the experiment. The goal is to calculate the depth map of an object using one light ...
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Hand eye calibration of robot arm using a 2D camera and marker of known size
If my understanding is correct, one flavor of hand eye calibration requires the following pairs of data for different robot arm positions:
The transform from the robot base to the robot hand.
The ...
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Which algorithms to locate a static 3D object relative to a moving camera/IMU?
I am using typical setup with camera and IMU as found on a smartphone. Using this, I would like to estimate the relative pose between the camera and an object (for simplicity, let's say a cube). The ...
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Question about Lens distortion
Suppose I have a 240x180 camera with the following distortion co-efficients,
$$k_1 = -0.138592767408$$
$$k_2=0.0933736664192$$
$$k_3=0.0$$
$$p_1=k_4=-0.000335586987532$$
$$p_2=k_5=0.000173720158228$$
...
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Accuracy of monocular visual-inertial odometry
I am currently considering to use monocular visual-inertial odometry (VIO) to localize a smartphone relative to a known object. Now, what I would like to understand is, what kind of accuracy I can ...
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Trigger two usb cameras at the same time
I'm studyng stereo cameras, and I want to build one. I searched a lot in internet, and the opinions are quite different about this topic.
Basically, my question is:
Can I synchronize two usb ...
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How to do IMU and camera "sensor fusion" tracking?
I have some 50ms latency cameras at hand and a 800Hz IMU (gyro+accelerometer+magnetometer). I would like to know how exactly how I should do a sensor fusion of such an IMU and camera to fix the ...
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Robot localization using sensor fusion (How to model the Extended Kalman Filter)?
I am new to the robotics field and sensor fusion as well.
I am trying to localize my robot using the data from my camera and the odometery through extended Kalman filter.
I have the data offline, I ...
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Vısual sensor.camera lenses with a field of view of more than 180 degree
What kind of camera models can be used for lenses with a field of view of more than 180 degree ?
Is ıt possible if not why?
Are fisheye lenses suitable for this purpose?
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Algorithm for orientation (pan/tilt) towards a moving point
Main Question:
note: The code in this question is pseudo-code, I'm using Python, but my pseudo-code is a mix of Python and C++.
I have a camera on the top of my robot's "head" which has pan and tilt ...
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what's the difference among rgb-d camera, depth camera, 3d camera, and stereo camera?
I'm very new in this field so my question may be very stupid. I apologize for this at first.
I'm trying to use a proper camera to run a SLAM algorithm. As suggested by some people, stereo camera may ...
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Extrinsic Calibration Target Depth Camera
What's a good calibration object for the extrinsic calibration (rotation + translation) of a depth camera (no color sensor, only depth)? With RGB, people seem to typically use chessboard pattern or ...
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What materials can I put in front of a RGB camera and LED IR lights to hide the sensors as much as possible?
I'm making a consumer camera prototype and want to make the front look as clean as possible. Right now I use a completely transparent material and the camera and the IR Lights (with their red hue) are ...
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Can you find object distance using camera pose
I have bounding boxes detected in RGB images, but no information about the camera's intrinsic properties. Using deep learning (preferably) can I find the distance to the object from the camera in real ...
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Stereo vision setup to obtain depth map
I am currently working on a project that requires me to obtain depth information and point cloud map of objects in an indoor environment ( roughly twice the size of a normal room). I would like to ...
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Finding the manufacturer for a sensor
We're building a smart camera and one of our competitors is using a depth sensor we're interested in using. If we open up the product, is it common to be able to see manufacturer information for ...
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Depth cameras with varying illuminations
We realized that depth cameras (IFM) tend to create a lot of noise when exposed in areas with direct sunlight. Are there any approaches to deal with illuminations? Eliminating pixels for instance?
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Image coordinate to robot coordinate
I am working with a Nao robot. One if the things I want to do is the following:
Take an image of geometrical objects in front of the Nao (done)
Extract features from the objects in the image, such as ...
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Smart camera image processing on embedded GPU vs. in the cloud
I'm working on a smart camera that does key point prediction (predicting locations of wrists, elbow, shoulder, ears, eyes, nose, etc.) for gesture recognition.
Right now, the neural net is running on ...
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OpenCV get topdown view of planar pattern by using intrinsic and extrinsic from cameraCalibrate
Originally I have a image with a perfect circle grid, denoted as A
I add some lens distortion and perspective transformation to it, and it becomes B
In camera calibration, A would be my destination ...
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Determining time difference of image capturing in multi camera setup
it is widely discussed in this forum, how to sync multiple cameras (e.g. best done via hardware trigger).
Now I'd like to know how to actually determine the time delay between two image streams and ...
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Poor accuracy of hand eye calibration when using vanilla Tsai's method
I’m working on the hand eye calibration for the robotic arm. I attached the camera near the tip of the robot (or end effector) and took around 40 pictures of an asymmetric circles pattern. I ...
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