Specifications

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With the model kinematically determinate we can proceed and run the KinematicAnalysis operation. Doing
so will show you the movement of the entire system as the pedal is rotating.
Now that the kinematics is in order, let us move on to the kinetic analysis in Lesson 8 and see what the
model is good for.
Lesson 8: Kinetics - Computing Forces
With the kinematic analysis in place we are ready to compute forces and investigate ergonomic properties of
the pedal arrangement. We shall presume that the pedal is loaded by a spring, the force of which the leg
must overcome when stepping on the pedal. AnyScript has a ligament class, which can be used to create
springs of various types. Please refer to the ligament tutorial
for further information. However, here we shall
take a simpler approach and simply define the spring force directly.
A force can be added to any kinematic measure by means of the AnyForce class. Because the concept of
kinematic measures is general, the AnyForce class attains the type given by the kinematic measure. If the
measure is a length, then an AnyForce is a force, and if it is an angle, the AnyForce automatically becomes a
moment. In the present case we shall add the AnyForce to the kinematic measure of the pedal's hinge. Let
us initially study the measure. Run the KinematicAnalysis again, open a ChartFX 2D View, and browse your
way through the tree to
Main.MyStudy.Output.Model.EnvironmentModel.HingeJoint.Pos. You should see the following graph: