Hello; I am trying to write a four bar program; it is not for school, but it is a personal project to refresh myself with programming and dynamics. I have a input with height 80 pixels, angular velocity of pi/12 rad/s and the initial angle is pi/2; the coupler is with length of 107.703296 pixels,an initial angle of .380506377 and the angular velocity was calculated to be 1.22597x10^-17 rad/s. the follower link's initial angle is pi/2 with a angular velocity of 0.1745329 rad/s and height of 120 pixels. I was assuming that linear equation would be (length*cos(initial angle + angular velocity*time),length*sin(initial angle+angularvelocity*time) but this only worked for the input link. so I know that the velocity of the second point on a rigid body is written as angular velocity of the first link cross product of the length and angle of the first point + the angular velocity of the second cross product of the length and angle of the second point.(adsbygoogle = window.adsbygoogle || []).push({});

2. Relevant equations

w1*r1*cos(phi1)+w2*r2*cos(phi2)+w3*r3*cos(phi3) = 0

-w1*r1*sin(phi1)-w2*r2*sin(phi2)-w3*r3*sin(phi3) = 0

w2 = -(w1*r1*cos(phi1)+w3*r3*cos(phi3))/(r2*cos(phi2))

w3 = -w1*r1*(-cos(phi1)*sin(phi2)+cos(phi2)*sin(phi1))/r3*(cos(phi2)*sin(phi3) - cos(phi3)*sin(phi2))

3. The attempt at a solution

I was using [x?,y?] = [r?*(cos(phi?+w?*t)),r?*sin(phi?+w?*t)), but this works only on the the input link

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# Homework Help: Help with a four bar equation

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