How can use a MATLAB value in Arduino Uno code?

Dear all,

I have a question regarding to sending information between MATLAb and an Arduino Uno. I have made a little Matlab program that detects red objects from a webcam, and labels their coordinates. Now i have a setup with an Arduino Uno that includes a servo. I want this servo to respond to the variable y-coordinate send from my matlab program. How do i do this?

my detection program is:

if true
  cam = webcam;       
  thresh = 0.29;      
  nFrame = 0;                                                                 

while(nFrame < 100)
  imgRGB = snapshot(cam);                                                

    imgGrey = imsubtract(imgRGB(:,:,1), rgb2gray(imgRGB));                  

    imgGrey = medfilt2(imgGrey, [3 3]);                                     

    imgGrey = im2bw(imgGrey, thresh);                                          

    imgGrey = bwareaopen(imgGrey,200);                                      

    bw = bwlabel(imgGrey, 8);                                               

    stats = regionprops(bw, 'BoundingBox', 'Centroid');                     

    imshow(imgRGB)                                                          

 hold on

    for object = 1:length(stats)
        bb = stats(object).BoundingBox;                                    
        bc = stats(object).Centroid;                                        
        rectangle('Position',bb,'EdgeColor','blue','LineWidth',1)           
        plot(bc(1),bc(2), '-m+')                                            
        a=text(bc(1)+15,bc(2), strcat('X: ', num2str(round(bc(1))), '    Y: ', num2str(round(bc(2)))));
        set(a, 'FontName', 'Arial', 'FontSize', 12, 'Color', 'blue');       
 end

 hold off   

 nFrame = nFrame+1;                                                      

 end

the value bw(2) is the y-coordinate that i want to use to move my servo. what is the corresponding code that i should use in arduino? and matlab?

regards,

Kasper NL

[khsuhhal qasimyar]

Hi!

I am khushhal qasimyar from afghanistan i have final project smart soccer bots , in vision system i need your code to detect the red color and move servo with it send me your code if posibale i really need it urgently my mail is [e-mail]

Answer 1

[Abhishek GS]

Hi Kasper van Wijk,

Once you have the MATLAB Arduino support package installed, go through this example which shows how to use the MATLAB Support Package to control a servo motor. Once you go through the example you will be able to modify it suit your algorithm of making the servo respond to 'bw(2)'.

Thanks, Abhishek

[Kasper van Wijk]

Thanks a lot for your quick reply, Abhishek! I really appreciate it! I finally managed to get something working, although I do still have some trouble with the communication between my arduino and macbook. After uploading a file onto my arduino once, it stops communication and gives the following error:

avrdude: ser_open(): can't open device "/dev/tty.usbserial-A702MVJ5": Resource busy
ioctl("TIOCMGET"): Inappropriate ioctl for device.

I looked it up, but i can't find a concrete solution to the problem. Now I just have to close and re-open Matlab and arduino everytime I want to upload a new script, or run my matlab script.

Do you have a solution for this as well?

grz.Kasper

Answer 2

[kwstis xoustoulakis]

Hello! I have built a robotic arm with 3 servo and a camera mounted on the upper arms. Looking a code to detect red objects via the camera and move the arm at them. I suppose that something similar u have built ....? If you can help I would appreciate it !!! Thanks

Answer 3

[Raphael Ferreira]

Hello! I'm from Brazil. I need your code to apply in a neurosurgery softwrae. Please, if you can, please send this red color code to my email. E-mail: <mailto:[e-mail] [e-mail]> I'm grateful already!

[Kasper van Wijk]

Please check your mail address. google says it doesn't exist...

[Raphael Ferreira]

Has arrived! Thank you!