Programs/code

Our robot uses a scissor mechanism which requires an optimization for selecting the correct dimension.

% Optimization on 4 Bar Mechanism

% Class: MAE156B

% Programmed by: Yau C. Yun, Keishi Tateda.

% Date: 01/26/2023

%% Given Parameter

Fs = 10;    % Fs = 10N from the spring force

Fg = 7;     % Force at point G = 7N

AE = 130;

EG = 80;    % EG

GEA = 70*pi/180;       %Angle GEA

%% Range of possible dimension

%%

% $Fa\cdot \overline{AC} - F_g\cdot \overline{CE} = 0$

DC = [0:1:130];   % DC: 0 mm to 130 mm

AC = [54:1:130];  % AC: 54 mm to 130 mm

DA_1 = 75.9;      % 75.9 mm

DA_2 = 60.9;      % 60.9 mm

%% Optimization

maxDC = 0;

maxAC = 0;

maxDAC_1 = 0;

maxdy = 0;

%  n = 1;

for j = 1:length(DC)

   for i = 1:length(AC)

       if abs((DA_1^2+AC(i)^2-DC(j)^2)/(2*DA_1*AC(i))) > 1

           continue

       end

       if abs((DA_2^2+AC(i)^2-DC(j)^2)/(2*DA_2*AC(i))) > 1

           continue

       end

       DAC_1 = acos((DA_1^2+AC(i)^2-DC(j)^2)/(2*DA_1*AC(i)));

       DAC_2 = acos((DA_2^2+AC(i)^2-DC(j)^2)/(2*DA_2*AC(i)));

       ycorn1 = AE*cos(DAC_1)-DA_1;

       ycorn2 = AE*cos(DAC_2)-DA_2;

       ytip1 = ycorn1 +cos(GFA-DAC_1)*EG;

       ytip2 = ycorn2 +cos(GFA-DAC_2)*EG;

      if ytip2-ytip1 > maxdy

          maxdy = ytip2-ytip1;

          maxDC = DC(j);

          maxAC = AC(i);

      end

   end

end

fprintf('\nThe maximum displacyment is %f mm\n', maxdy)

fprintf('length of DC %d mm\n', maxDC)

fprintf('Length of AC is %d mm\n', maxAC)