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10.2.1 Describe linear, rotary, intermittent, oscillating, reciprocating and irregular motion.
10.2.2 Explain how linkages can be used to change the direction of motion of components.
Simply, linkages are a set of connected levers that can change the direction of motion, i.e linear into rotational.
10.2.3 Discuss mechanical motion in a range of contexts.
Consider a hydraulic digger, a bicycle, a car jack and a hand drill.
10.2.4 Define torque.
10.2.5 Discuss the design features of a ratchet and pawl system.
Ratchet and pawl mechanical device that permits motion in one direction only. The ratchet is usually a wheel with slanting teeth. The pawl is a lever tangential to the wheel with one end resting on the teeth. When the wheel rotates one way, the pawl slides over the teeth; when the wheel rotates the other way, the pawl catches in the teeth.
"ratchet and pawl." The Columbia Encyclopaedia, Sixth Edition. 2008. Encyclopedia.com. 14 Apr. 2009 <http://www.encyclopedia.com>.
10.2.6 Describe simple cam shapes and their advantages.
10.2.7 Identify cam followers and state their use.
The follower (cam follower) simply traces the surface of the cam which produces different types of oscillating motion which is dependent on the shape of the cam.
10.2.8 Explain the use of a series of cam and follower mechanisms to achieve a set purpose.
This can be explored in a number of ways: using Lego, paper and pins, or through virtual online models.
Bulleted list and italicised paragraphs are excerpted from Design Technology: guide. Cardiff Wales, UK: International Baccalaureate Organization, 2007.
Images are clickable links to its location.