Week 2- 2R Robotic Arm Challenge

Aim = Programme to simulate the forward kinematics of 2R robotic arm

• create an animation file on plot and uploading animation

Theory =

1. Step wise explanation of code

• firstly we need to give inputs i.e. values of l1 & l2 , theta1 & theta2.
• now we get 3 coordinates from the fig and the derivation where the base of the robot is (x0 y0).
• now the end point of link 1 are (x1 y1) and finally the end point of link 2 are (x2 y2).
• here by deriving formulae we can write code as mentioned in code.
• now we need to plot the graph for both robotic arm.
• here we need to make animation of these robotic arm with different values of theta1 and theta2
• here we need to use linspace command for values of theta 1 and theta 2.
• now we need to use function of for loop for values of theta1 & theta2
• here again we need to plot the graph for new code with using function of linewidth
• use function of counter for as each time for loop is executed there increase value of counter (ct) = ct+1
• as now we execute our programme we get plots overwritten so now we use the command hold on to not overwritten plots
• now we will use pause(0.3)
• now accounding to thetaa1 values of theta2 changes
• now we need to fix the axis so changwe x limits and y limits
• now we need to make Movie of code so we use frame command (getframe(_))
• now we need to make videofile using command videofile
• now the lastcommand use is close(videofile)

Errors faced during programme and steps to slove it =

Not able to use values of theta1 & theta2 as we need to use there for loop

clear all
close all
clc

% Inputs
l1 = 1;
l2 = 0.5;
theta1 = linspace(0,90,10);
theta2 = linspace(0,90,10);
ct=1;
for i = 1:length(theta1)
    THETA1 = theta1(i);
    for j = 1: length(theta2)
    THETA2 = theta2(j);
    x0 = 0;
y0 = 0;
x1 = l1*cosd(THETA1);
y1 = l1*sind(THETA1);
x2 = x1 + l2*cosd(THETA2);
y2 = y1 + l2*sind(THETA2);

% plotting


plot([x0 x1],[y0 y1],[x1 x2],[y1 y2],'linewidth',3);
axis([-0.1 1.5 0 1.5])
pause(0.3)

M(ct) = getframe(gcf);
ct = ct+1;
    end
    
end
movie(M)
videofile = VideoWriter('forward_kinematics.avi','Uncompressed AVI');
open(videofile)
writeVideo(videofile,M)
close(videofile)