EST2 in chapter 7 Matlab code of the exercise 7.1.1.1 2-Dimensional (Planar) Robotic Arms (chapter7.mlx)

[ocaravaca]

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What environment are you using

Are you using MATLAB Online or desktop? If desktop what operating system?

Desktop / Windows / Matlab R2024b

Let's check your installed software

Include the results of running

>> rvccheck

Results:

rvccheck
rvccheck for RVC3 Toolbox
Some required Toolboxes are not installed:
Navigation Toolbox is required for Chapter 5
You have Peter Corke's Robotics and/or Spatial Math Toolbox in your path

This is strange because the Navigation Toolbox is actually installed:

If this doesn't run, or produces no output please note that fact. It would mean something is very wrong with your MATLAB path or toolbox installation.

Describe the bug
A clear and concise description of what the bug is.

In chapter 7 Matlab code of the exercise 7.1.1.1 2-Dimensional (Planar) Robotic Arms (chapter7.mlx)
There is a bug when running the code:

>>a1 = 1;a2=5;
>>e = ETS2.Rz("q1")*ETS2.Tx(a1)
e = 
Rz(NaN)Tx(1)

This is later another problem when trying to run:

>> e.fkine(pi/6)
Operator '*' is not supported for operands of type 'string'.

Error in ETS2/fkine (line 143)
                        r = r * tform2d(0,0,v*opt.deg);

>> e.teach;
Error using zeros
NaN and Inf not allowed.

Error in ETS2/teach (line 388)
                q = zeros(1,robot.n);

The expected behavior is the one described in chapter 7 of the book "Robotics, Vision
and Control Fundamental Algorithms in MATLAB®", 3rd edition 2023 and starting from page 278.

[ocaravaca]

Apparently, the problem is the use of "q1" in the code, so the error comes from using "" in the argument just as:

e = ETS2.Rz("q1") *ETS2.Tx(a1)
Instead, we should use 'q1' >>e = ETS2.Rz('q1') * ETS2.Tx(a1) and it works.
So, the issue is closed for me I guess.