Tipping is the type of motion created by a force acting at a distance from the CR.
Tipping has two (2) components - translation and rotation.
Tipping = Translation + Rotation
Pure translation occurs when a force is applied through CR.
Pure rotation occurs when a couple acts on an object.
If you combine the two components of tipping, you get the following:
Remember: Fa = Fb = Fc
Fa and Fb alone create a couple
Fb and Fc alone create no net movement
Since Fb and Fc cancel each other, the following equality is true:
Joining all of the above information together allows you to describe the motion of tipping.
Uncontrolled Tipping Versus Controlled Tipping
Uncontrolled Tipping (UT) is the motion created by a single force acting at a distance for the center of resistance (CR).
Note: UT is the type of motion that has been discussed thus far.
An example of uncontrolled movement is a car that only has the ability to accelerate. Truly a car without the ability to decelerate is out of control.
A car requires accelerating and decelerating systems to control movement. Tipping objects require the application of a second force system to regulate movement.
Controlled Tipping (CT) is the motion of an object that has a force applied at a distance from CR and a counterbalancing couple (CBC) to regulate the rotation of the object.
Counterbalancing Couple (CBC) is a couple that creates a moment that is opposite in direction to the moment created by the force responsible for UT. CBC controls UT.
CBC allows you to control tipping in three ways:
CBC's moment < F's moment ...
CBC's moment = F's moment, translation results! For example...
CBC's moment > F's moment ...
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Last Update: August 20,1998
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