simulink error about the sl_arm_ibvs

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Jin

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Apr 26, 2018, 3:20:36 AM4/26/18
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Dear everyone,
I am trying to run sl_arm_ibvs, but there are some errors described as follows:
"Evaluation of expression resulted in an invalid output. Only finite double vector or matrix outputs are supported"

It says the error is in the function 'slcamera'. However, I have installed the function, and there is no error when I run sl_ibvs .

I'm using Matlab R2017b and i've installed the latest versions of both RTB and MVTB.
Could you please help to give a solution?
Thank you so much!
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Peter Corke

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Apr 28, 2018, 9:19:34 PM4/28/18
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Jin, thanks for testing this code, I think you are one of the very few.

I cannot replicate this error, my model runs fine using code from the distributed toolboxes.  The things I would do to resolve this:

- start a brand new MATLAB session

If that doesn't help, then you'll need to do some debugging.

- First modify slcamera so the first 2 lines look like this

function p = slcamera(cam, u)

    u'


- From Simulink window menu, select View/Diagnostic View which brings up a new window, it will show the values now being passed to slcamera

- Run the simulation

- After it fails cut and paste the output of the diagnostic view to me.
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Jin

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May 24, 2018, 2:18:21 AM5/24/18
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Thank you for your reply! I modify slcamera like this:

function p = slcamera(cam, u)
       u'
    if all(u == 0)
        % Simulink is probing for the dimensions
        np = (length(u)-16)/3;
        p = zeros(2, np);
    else
        P = reshape(u(17:end), 3, []);
        Tcam = reshape(u(1:16), 4, 4);
        p = cam.plot(P, 'pose', Tcam, 'drawnow');
    end

and get the diagnostic view:

Peter Corke

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Jun 17, 2018, 8:14:36 AM6/17/18
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It's not clear to me, is this now solved, or still a problem?

Jin

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Jul 11, 2018, 2:52:56 AM7/11/18
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Thank you for your reply! It's solved now!

在 2018年6月17日星期日 UTC+8下午8:14:36,Peter Corke写道:

yuchen...@gmail.com

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Mar 9, 2019, 4:17:48 PM3/9/19
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Hi Jin,
I also run into this problem when I run the simulation. I've already modified the .m file slcamera but the error is still there. Can you tell me how did you fix the error?
Thank you very much!

Peter Corke

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Mar 16, 2019, 7:00:44 PM3/16/19
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are you sure the new slcamera.m is on your path.  Use the which command to check.  Are you getting exactly the same error as the other people?

peter

Xihu milk

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May 18, 2022, 11:13:31 AMMay 18
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Dear everyone,
I also run into this problem when I run the simulation and I've already modified the .m file slcamera but the error is still there.  Meanwhile , the sl_ibvs  can be run well.  I'm using Matlab R2021b and i've installed the latest versions of both RTB and MVTB. Could you please help to give a solution?
Thank you very much!

jianyou qi

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Jun 13, 2022, 3:54:05 AMJun 13
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"Evaluation of expression resulted in an invalid output. Only finite double vector or matrix outputs are supported", Dear Jin, you said you had solved this problem, can you  explain the process how to deal with this issue? thank you very much
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