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what's the difference among rgb-d camera, depth camera, 3d camera, and stereo camera?

3D/Depth-Camera: The most inclusive terms, only means that the camera gives you 3d data. Stereo-Camera: One kind of 3D-Camera, consists (in most cases) of two gray-scale Cameras. RGBD-Camera: A ...
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9 votes

Camera selection for long range stereo vision system (up to 100 meters)

I still think this is off-topic, but it seems I need more space than a comment to show (answer?) why that is so. You are starting from some performance specifications and are looking to get to a set ...
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8 votes
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Can I control more than 18 servo motor with a Raspberry Pi

Raspberry Pi has only one hardware PWM channel and Linux distribution it runs is not a real time system, so software PWM may be very unstable. You are not guaranteed, that your program will be ...
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8 votes

Drones and camera streaming

It all depends on the video quality that you require. The short answer is to use a 3G or 4G transmitter, assuming that you are in an area with mobile coverage, to either a local device (Mobile phone) ...
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5 votes
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Low power computer for stereo vision

You probably are asking too much of inexpensive components. The raspberry Pi does not have 2 camera connections, but its brother, the Pi Compute board does. http://makezine.com/2014/11/03/stereo-...
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4 votes

algorithm Simple Stereo Vision

The first thing is to make sure that the cameras will get the coordinates of the object at the same time (I don't know if Pixy has a FREX or STROBE signal for synchronization), or that the object is ...
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  • 41
4 votes

Drones and camera streaming

Common solutions are from those who fly FPV (First Person View), they use simple analog cameras connected to 900 MHz, 2.4 GHz, and 5 GHz the lower the frequency generally the longer the transmission ...
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  • 1,909
4 votes

Can I control more than 18 servo motor with a Raspberry Pi

You need a controller like this that can address them individually over I2C. These can be chained together to control more than you'll likely ever need: Adafruit 16-Channel 12-bit PWM/Servo Driver - ...
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4 votes

Question for those who have experience using stereo cameras/module (e.g. ZED, DUO M, Bumblebee, etc.)

My experience with ready-made stereo solutions is that they (as @Ben has said) provide you with synchronized image pairs and well-defined baseline geometry. If you are on a low-budget, and you have ...
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4 votes
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Real-time video processing on video feed from a drone's camera

This AR.Drone provides SDK, therefore, you can access the images on real-time. It is fully compatible with Linux. They have examples also for smartphones. I believe android and iPhone. It has two ...
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4 votes

Why are two cameras mounted in paralle in stereo application?

Each camera needs to be defined by 6 variables (3 position, 3 orientation). This would mean that during the calibration process, a solver needs to find 12 variables. As this is done usually with an ...
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4 votes
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Smart camera image processing on embedded GPU vs. in the cloud

Performance differences between using an embedded GPU vs. the cloud? For your context (to my mind, gesture recognition would ideally be realtime), the latency of going over the cloud would push me ...
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3 votes
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Simple way of 3d perception

The best answer is probably going to be an ultrasonic sensor on a servo, you can get them in a huge range of values, from very close to very far range depending on your application, and varying beam ...
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3 votes
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Interfacing high-resolution image sensors with ARM Board

I would like to suggest you to use Beaglebone Black , it is smaller than size compared to Raspberry pie. It is just the size of a credit card. And has a faster processor of 1 GHz and has an inbuilt 3D ...
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3 votes

What are some low cost alternatives for lidar?

This representative sample of what's out there may give you some idea of what's out there at various price points: Unfortunately, you're talking several thousand dollars for an outdoor unit with 10's ...
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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: ...
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3 votes

Real-time video processing on video feed from a drone's camera

I bought an AR done 2.0 for my research. I used Labview to process the realtime video feed from either the bottom camera of the drone or the front camera. You can read more details on how to setup ...
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3 votes
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How to produce a continuous variation of a discontinuous function?

It happens many times that set-points fed in our systems do change in a step-wise manner. Your intuition of filtering those variations is correct and represents a common practice. Here I'd give two ...
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3 votes
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Difference between 3D Camera(using IR projection) and Stereo Camera?

"3D camera" is a generalisation that covers sensors that can observe a point-cloud or depth map of the scene they are observing. Some 3D cameras use a projector (via various ways) to improve the ...
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3 votes

Stereo Camera calibration with different camera types

It looks like what I saw when a colleague of mine was working with fisheye lenses; I found this post after doing an image search for "rectify fisheye image" and following the link from this picture. ...
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3 votes

Camera selection for long range stereo vision system (up to 100 meters)

I'll try to explain this in terms of software. Firstly, it is just next to impossible to have 100 metres (practically, 3 metres is like the best depth accuracy) and we need to be sure that the cameras ...
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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 ...
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3 votes
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Question about Lens distortion

You can only say that the distorted image coordinates are in the range (0-240, 0-180), since that's the image you are starting with. Typically you assume the dimensions of the undistorted image as ...
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3 votes
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Position vs Image based visual servoing?

The problem in both cases is to move the robot tool to some pose relative to an object. Let's assume the camera is attached to the end of a robot arm (eye in hand case) so we will consider this a ...
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  • 1,522
2 votes

Calculate object distance with camera

Think of it this way, cameras measure angles. Each pixel tells you the angle between the camera's central axis and the object/corner/etc shown at that pixel. So if you know real-world dimensions of ...
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  • 2,679
2 votes

What are some low cost alternatives for lidar?

Your cheapest option will probably be to use a ultrasonic sensor on a stepper, by advancing the server one step and reading the distance. The only downside to this will be the resolution you can get, ...
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2 votes

What are some low cost alternatives for lidar?

I don't have enough reputation to comment, but I'll add my 2cents in an answer. Basically you're limited to lidar mapping if you want any decent fidelity. Stereoscopic imaging via OpenCV in one ...
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2 votes
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Conceptual problem regarding electronic shutters

Shutter speed is a synonym for exposure time. Exposure time is linked to the frames per second (FPS): $t_{exposure} + t_{readout} \leq 1 / {FPS}$ So the answer to your question is: no. FPS is ...
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2 votes

How can I make a motion tracking camera?

Basically you need to solve 3 different problems: Find the right camera setup and recording strategy I'm not an expert in this field so I won't say anything to this Second get the information about ...
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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 ...
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