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CalculateMechanicalAdvantage

CalculateMechanicalAdvantage[linkage, inp, out]
Calculate the mechanical advantage between input force (or torque) inp and output force ( or torque) out. The result is the ratio between inp/out forces that balances the mechanism.
  • inp and out are either force or torque names defined in the linkage[["$Forces"]] or the linkage[["$Torques"]] records.
  • The mechanical advantages is calculated by calculating the power of input and output forces ( or toques). The powInput+x*powOutput = 0 equation is solved for x. The mechanical advantage is the resulted x.
  • The mechanical advantages might result in a symbolic expression. The numerical result of the mechanical advantages can be calculated if the substitution rules of the linkage is substitute.
  • The input and output forces are normalized to unit vectors. The result of the CalculateMechanicalAdvantage function (x) can be interpreted as such that given a unit input force or torque vector inp, the linkage is balanced if the output force or torque vector acting in the same direction as out having the magnitude of x.
EXAMPLESCLOSE ALL
Basic Examples   (1)
Load LinkageDesigner package
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Load the example crank slider linkage
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Define a force on the slider link (link3) at point {0,0,0}. The force vector is defined w.r.t. LLRF of link3 and the vector is {-1,0,0}
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Define a torque on link1 that act along the joint's axis
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Display the linkage and the forces
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Show the LinkageData database
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Calculate the mechanical advantage between F1 force and T1 torque
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The mechanical advantage is depending on the posture of the mechanism, therefor the most complete view of the result can be obtained by plotting the mechanical advantage factor w.r.t joint variable of the mechanism.
Plot the mechanical advantage function w.r.t the q1 joint variable, which is the joint variable
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Display the mechanism in the position (q1 → 68.4 °), where the mechanical advantages is the maximum
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