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 l OA  sin   l AB  sin   l  O 1B  sin  ,
2
2
1
3
3
1
l OA  cos   l AB  cos   l O 1B  cos  ,
1
3
3
2
1
2
 l O 1C  sin  3  l CD  sin  4  0 , (1.8)
4
3
l O1 C  cos 3  l  4 cos 4  V .
D
3
CD
After differentiation we got system of linear equations with
unknown velocities ,  ,  and V .
D
2
3
4
System of the equations (1.3) and (1.8) or (1.6), (1.7) and
(1.8) are solved together by MathCAD app.
Writing the program. During writing the program,
magnitudes of given parameters should be specify at beginning.
Next, create cycle for calculations because we need to do
calculating for given positions of input link. For example for cycle
of calculations, we must create ranging variable as number of input
link’s positions – n, with zero initial position and step equals 1 and
final value 12. Mentioned information will look on display like:
n : 0, 1.. 12.
Magnitude of the angle  for every separate number of
1
input link’s position will take next view in the program:

where  – angle that describe initial position of a crank;
0
   2  / n – step of changing angle  .
1
Taking into account mentioned, the beginning part of program
looks like:

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