# TwoPulleys12D

TwoPulleys1[cnum, point1, rad1, point2, rad2, dist, C] models a chain and sprocket or belt set. The rotational positions of the sprockets are related as per their respective radii.
• The constant C sets the initial rotational position of the pulleys.
TwoPulleys1 constrains one degree of freedom.

• The radii of the two sprockets cannot be equal; use RotationLock1.
• The constant C, which sets the initial rotation of the pulleys, is given by the formula C = (rad1 e1 - rad2 e2) where e1 and e2 are determined in the following way. Place the two sprockets in any valid position and construct a vector from point1 to point2. e1 is the angle, measured in radians, from the constructed vector to the local x axis of the first sprocket and e2 is the angle from the constructed vector to the x axis of the second sprocket.
TwoPulleys1 is functionally identical to
TwoPulleys2 except that the distance between the two pulleys is not constrained, only their angular orientation.
• If the Euler solution method is specified, TwoPulleys1 generates two constraints, and adds one extra variable to the model.
TwoPulleys1[cnum, point1, rad1, {sym1, guess}, point2, rad2, dist, C] can be used to explicitly specify the name of the extra variable, and its initial guess. Otherwise, a symbol of the form cnum is used.
• The first, and optional second, equation in TwoPulleys1 relates the rotation angles of the two pulleys.