Robot camera + motion detection - camera

I have a project in which we (me and my student) will develop a system for robot.
In this robot we have a camera that capture.
My question is how to detect motions, movements.
Is there a solution?? Which technics and tools to use ??
Which language to use (possible for Java for example) ??
Thanks in advance.
Best regards.
Ali

Consider using OpenCV:
http://opencv.org
It has a lot of useful vision algorithms built in, and supports, C, C++ and Python, as well as GPU functionality.

I will suggest you Microsoft Visual Studio wich is an integrated development environment and c# programming language. Emgu CV library wich is a cross platform .Net wrapper to the OpenCV image processing library. A simple method from a static position is this:
Convert a single frame to grayscale.
Convert a new frames from real time into grayscale.
Make abstractions between the first frame and new frame from real time.
The result of this is a third, new frame comprised of the differences between the first two. Use erosion and thresholding for that to get a frame with white representing the motioned section and black representing the rest of the space.
If the objects you attempt to track have a distinct color, you should be able to target them adequately.
One way to accomplish this is to choose an appropriate space for color as RGB space. Keep in mind this may be too sensitive, even to small illumination variance. (It really depends on the objects you want to track and tracking scenario.)

You can use OpenCV
Here you can find a C++ tutorial: http://blog.cedric.ws/opencv-simple-motion-detection

using two cameras instead of one could be useful in your project, for detecting depth in the image and real distance of a motion (in a perspective vision)
Stereoscopic depth rendition
Real-time detection of independent motion using stereo

Related

Is programming a voxel based graphics API theoretically possible?

This is entirely a theoretical question because I understand the time it would take to do such a thing would be ridiculous
I've been working with "voxels" a lot lately and the only way I can display them to a user is to either triangulate the visible surfaces or make a CPU ray-tracer but both come with their own problems.
Simply put, if we dismiss the storage space needed for voxel meshs and targeted a very specific GPU would someone who was wanting to create a graphics API like OpenGL but with "true" voxel primitives that don't need to be converted be able to make such thing or are GPUs designed specifically for triangles with no way to introduce a new base primitive?
Its possible and it was already done many times
games like Minecraft,SpaceEngineers...
3D printing tools and slicers
MRI/PET scans tools
Yes rendering on GPU is possible with the two base methods you mention. Games usually use the transform to boundary representation 3D geometry. With rise of shaders even ray tracers are now possible here mine:
simple GLSL voxel ray tracer
using native OpenGL architecture and passing geometry as 3D texture. In order to obtain speed you need to add BVH or similar spatial subdivision of geometry...
However voxel based tools have been here for quite some time. For example many isometric games/engines are voxel based (tile is a voxel) like this one:
Improving performance of click detection on a staggered column isometric grid
Also do you remember UFO ? It was playable on x286 and it was also "voxel/tile" based isometric.

Custom rendering with GPU, Direct3D or OpenGL

I have a Windows application that currently renders graphics largely using MFC that I'd like to change to get better use out of the GPU. Most of the graphics are straightforward and could easily be built up into a scene graph, but some of the graphics could prove very difficult. Specifically, in addition to the normal mesh type objects, I'm also dealing with point clouds which are liable to contain billions of Cartesian stored in a very compact manner that use quite a lot of custom culling techniques to be displayed in real time (Example). What I'm looking for is a mechanism that does the bulk of the scene rendering to a buffer and then gives me access to that buffer, a z buffer, and camera parameters such that I can modify them before putting them out to the display. I'm wondering whether this is possible with Direct3D, OpenGL or possibly use a higher level framework like OpenSceneGraph, and what would be the best starting point? Given the software is Windows based, I'd probably prefer to use Direct3D as this is likely to lead to fewest driver issues which I'm eager to avoid. OpenSceneGraph seems to provide custom culling via octrees, which are close but not identical to what I'm using.
Edit: To clarify a bit more, currently I have the following;
A display list / scene in memory which will typically contain up to a few million triangles, lines, and pieces of text, which I cull in software and output to a bitmap using low performing drawing primitives
A point cloud in memory which may contain billions of points in a highly compressed format (~4.5 bytes per 3d point) which I cull and output to the same bitmap
Cursor information that gets added to the bitmap prior to output
A camera, z-buffer and attribute buffers for navigation and picking purposes
The slow bit is the highlighted part of section 1 which I'd like to replace with GPU rendering of some kind. The solution I envisage is to build a scene for the GPU, render it to a bitmap (with matching z-buffer) based on my current camera parameters and then add my point cloud prior to output.
Alternatively, I could move to a scene based framework that managed the cameras and navigation for me and provide points in view as spheres or splats based on volume and level of detail during the rendering loop. In this scenario I'd also need to be able add cursor information to the view.
In either scenario, the hosting application will be MFC C++ based on VS2017 which would require too much work to change for the purposes of this exercise.
It's hard to say exactly based on your description of a complex problem.
OSG can probably do what you're looking for.
Depending on your timeframe, I'd consider eschewing both OpenGL (OSG) and DirectX in favor of the newer Vulkan 3D API. It's a successor to both D3D and OGL, and is designed by the GPU manufacturers themselves to provide optimal performance exceeding both of its predecessors.
The OSG project is currently developing a Vulkan scenegraph known as VSG, which already demonstrates superior performance to OSG and will have more generalized culling ability.
I've worked a bunch with point clouds and am pretty experienced with them, but I'm not exactly clear on what you're proposing to do.
If you want to actually have a verbal discussion about the matter, I'm pretty easy to find (my company is AlphaPixel -- AlphaPixel.com) and you could call us. I'm in the European time zone right now, it's not clear from your question where you are but you sound US-based.

Robot odometry in labview

I am currently working on a (school-)project involving a robot having to navigate a corn field.
We need to make the complete software in NI Labview.
Because of the tasks the robot has to be able to perform the robot has to know it's position.
As sensors we have a 6-DOF IMU, some unrealiable wheel encoders and a 2D laser scanner (SICK TIM351).
Until now I am unable to figure out any algorithms or tutorials, and thus really stuck on this problem.
I am wondering if anyone ever attempted in making SLAM work in labview, and if so are there any examples or explanations to do this?
Or is there perhaps a toolkit for LabVIEW that contains this function/algorithm?
Kind regards,
Jesse Bax
3rd year mechatronic student
As Slavo mentioned, there's the LabVIEW Robotics module that contains algorithms like A* for pathfinding. But there's not very much there that can help you solve the SLAM problem, that I am aware of. The SLAM problem consist of the following parts: Landmark extraction, data association, state estimation and updating of state.
For landmark extraction, you have to pick one or multiple features that you want the robot to recognize. This can for example be a corner or a line(wall in 3D). You can for example use clustering, split and merge or the RANSAC algorithm. I believe your laser scanner extract and store the points in a list sorted by angle, this makes the Split and Merge algorithm very feasible. Although RANSAC is the most accurate of them, but also has a higher complexity. I recommend starting with some optimal data points for testing the line extraction. You can for example put your laser scanner in a small room with straight walls and perform one scan and save it to an array or a file. Make sure the contour is a bit more complex than just four walls. And remove noise either before or after measurement.
I haven't read up on good methods for data association, but you could for example just consider a landmark new if it is a certain distance away from any existing landmarks or update an old landmark if not.
State estimation and updating of state can be achieved with the complementary filter or the Extended Kalman Filter (EKF). EKF is the de facto for nonlinear state estimation [1] and tend to work very well in practice. The theory behind EKF is quite though, but it should be a tad easier to implement. I would recommend using the MathScript module if you are going to program EKF. The point of these two filters are to estimate the position of the robot from the wheel encoders and landmarks extracted from the laser scanner.
As the SLAM problem is a big task, I would recommend program it in multiple smaller SubVI's. So that you can properly test your parts without too much added complexity.
There's also a lot of good papers on SLAM.
http://www.cs.berkeley.edu/~pabbeel/cs287-fa09/readings/Durrant-Whyte_Bailey_SLAM-tutorial-I.pdf
http://ocw.mit.edu/courses/aeronautics-and-astronautics/16-412j-cognitive-robotics-spring-2005/projects/1aslam_blas_repo.pdf
The book "Probabalistic Robotics".
https://wiki.csem.flinders.edu.au/pub/CSEMThesisProjects/ProjectSmit0949/Thesis.pdf
LabVIEW provides LabVIEW Robotics module. There are also plenty of templates for robotics module. Firstly you can check the Starter Kit 2.0 template Which will provide you simple working self driving robot project. You can base on such template and develop your own application from working model, not from scratch.

Dual kinect calibration using powerfull IR LED illuminator

i am using multiple Kinects within the scene. So I need to calibrate them and find the extrinsic parameters like translation and rotation world coordinate system. Once I have that information, i can reconstruct the scene at highest level of accuracy. the important point is : i want to get submillimeter accuracy and may be it would be nice if i could use powerfull IR projector in my system. But i do not have any Background about IR sensor and calibration methods. So i need to know about tow subject : 1- is it possible to add IR LED illuminator to kinect and manage it? 2- if i could add how to calibrate my new system?
Calibration (determining relative transforms (rotation, scale, position)) is only part of the problem. You also need to consider whether each Kinect can handle the interference of the other Kinect's projected IR reference patterns.
"Shake n Sense" (by Microsoft Research) is a novel approach that you may be able to use that has been demonstrated to work.
https://www.youtube.com/watch?v=CSBDY0RuhS4

How to avoid a double-up of effort for retina, when using tile maps from Tiled with Cocos2d

I've got retina tile maps working, 15x10 tiles, of 64x64 tiles. problem is for non-retina devices I will need to make a 15x10 tiles of 32x32 tiles. I don't want to recreate the Tile, is it just a case of changing the XML (.tmx) file? Is there an automated tool or another way around this? I've been looking online but not getting too much help.
Thanks
You have to update the TMX file and scale certain attributes. Unless your TMX map is very simple this will be a tedious and error-prone task that's best left to a tool.
There are a variety of TMX rescaling tools out there, but some didn't work for me or simply were incomplete at the time (ie one didn't scale object layers). All the tools I know are generally are written in rather unusual languages (for an iOS developer at least) like Python, Ruby or Bash scripts. Others are only available as binary without the source code.
Check out this cocos2d forum post. Specifically this tool or HDx on the App Store. iTilemaps might also work for you.
Because I wasn't happy with either of the choices, I wrote my own command line tool tmx2scale in Objective-C to rescale TMX maps intelligently in all directions. The tmx2scale tool is not currently available but it will be distributed complete with source code with the KoboldScript Game Kit project.