Module 6 General Screws (twists and wrenches). Statics. Kinematics. Forces in parallel. Joints in series. Can they be reduced to a single force? ( Poinsot’s theorem ). Can they be reduced to a single joint? ( Chasles’ theorem). Recall An axiom of statics. - PowerPoint PPT Presentation
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Module 6General Screws(twists and wrenches)
Forces in parallelJoints in seriesStaticsKinematicsCan they be
reduced to a single force? (Poinsots theorem)Can they be reduced to
a single joint? (Chasles theorem)
RecallAn axiom of staticsTwo force systems are equivalent if and
only if: They have the same resultant force They have the same
moment with respect to some point
Moment of a pure coupleOr-FFAB
Poinsots central axis theorem
Concurrent forces can be added using the parallelogram
ruleOP
The shifting operation (in statics)
The moment of two pure couples (with respect to any point) is
the sum of their moments
The alignment operation (in statics)
The alignment operation (in statics)
The alignment operation (in statics)
Chasles screw axis theorem
Concurrent angular velocities can be added using the
parallelogram rule
The shifting operation (in kinematics)
Translational velocities can always be added
The alignment operation (in kinematics)
The alignment operation (in kinematics)
The helicoidal velocity field
Can be seen as a rotation about the origin, plus a slidingTwists
reinterpreted
