Merge branch 'HEAD' of https://gitlab.com/kakila/windturbine_HSR.git

experimental_setup/doc/mfile_structure.md

+Comment block 1: license, e.g. GPLv3
+
+Comment block 2: author, e.g. 
+   ## Author: Juan Pablo Carbajal <ajuanpi+dev@gmail.com>
+
+Comment block 2: help of the function
+  1. Matlab help style
+  2. Octave help style, uses texinfo
+ 
+ 
+function [list of output args] = function name ( list of input args )
+
+  function code here!
+
+end%function
+
+Comment blocks: Tests (unit tests)
+
+Optional Comment blocks: Demos (example how to use function, with plots if possible)
+

experimental_setup/sandbox/maxonRE50_model.m

+## Copyright (C) 2017 - Simon Hasler
+## Copyright (C) 2017 - Juan Pablo Carbajal
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+## Author: Hasler Simon <simon.hasler@hsr.ch>
+
+## -*- texinfo -*-
+## @defun {[@var{T} @var{W}] =} maxonRE50_model (@var{V}, @var{I})
+## @defunx {[@dots{} @var{Tg} @var{Wg}] =} maxonRE50_model (@var{V}, @var{I}, @var{gear})
+## Returns the torque @var{T} and rotational speed @var{W} of the DC-motor Maxon RE50 
+## based on the aplied voltage @var{V} and current @var{I}.
+##
+## @var{V} should be in volts and @var{I} in amperes.
+## @var{T} is given in Nm and @var{W} in rad/s.
+##
+## If a gearbox is attached to the motor, the reduction ratio  and its efficinecy
+## should be given in the structure @var{gear}.
+## The reduced speed and torque are returned in @var{Tg} and @var{Wg}. 
+##
+## Reference: @url{https://www.maxonmotor.com/maxon/view/product/370354}
+## @end defun
+
+function [T W Tg Wg] = maxonRE50_model (V, I, gear = [])
+
+  ## Datasheet values
+  kM   = 242;   # Torque constant [mNm/A].
+  kn   = 39.5;  # Rotational speed constant [rpm/V] 
+  dndM = 0.638; # Speed-Torque gradient [rpm/mNm].
+
+  fT = (1/1e3);               # conversion factor mNm --> Nm
+  fW = (2*pi / 1) * (60 / 1); # conversion factor rpm --> rad/s
+
+  # Results. 
+  # See: https://www.maxonmotor.ch/medias/sys_master/8802918137886/maxon-Formelsammlung-de.pdf (German)
+  #      http://storkdrives.com/wp-content/uploads/2013/10/1-Formelsamling.pdf (English)
+  # Section 6.3
+  T = kM * I;            # torque [mNm]
+  W = kn * V - dndM * T; # speed [rpm]
+
+  # Conversion
+  T *= fT;
+  W *= fW;
+
+  Tg = T; Wg = W;
+  if !isempty (gear)
+    Wg /= gear.ratio;
+    Tg *= gear.ratio * gear.efficiency;
+  endif
+
+endfunction
+
+%!demo
+%! P = 200; # Power in Watts
+%! V = linspace (70, 300, 100).';
+%! I = P ./ V;
+%! [T W] = maxonRE50_model (V, I);
+%!
+%! figure (1);
+%! plot (T * 1e3, W /2/pi/60, '-k','linewidth', 2);
+%! grid on
+%! axis tight
+%! xlabel ("Torque M [mNm]")
+%! ylabel ("Ang. speed [rpm]");
+%! title ("Torque-Speed curve @ 200W")
+
+%!demo
+%! P = 200; # Power in Watts
+%! V = linspace (70, 300, 100).';
+%! I = P ./ V;
+%! gear_GP52 = struct ('ratio', 4.3, 'efficiency', 0.91);
+%! [T W Tg Wg] = maxonRE50_model (V, I, gear_GP52);
+%! figure (1);
+%! plot (Tg * 1e3, Wg /2/pi/60, '-k','linewidth', 2);
+%! grid on
+%! axis tight
+%! xlabel ("Torque M [mNm]")
+%! ylabel ("Ang. speed [rpm]");
+%! title ("Torque-Speed curve @ 200W with 4.3:1 gear")
+