Dynamics of Machines Assignment

Part A) Planar Kinematics

You are asked to design a slider crank and rocker mechanism such that you achieve a slider movement output of:

x(t) = D + 0.2(1-cosθ)

where θ is the angle of the input crank relative to the horizontal axis.

The center of the input crank, D, is given for the mechanism as 1m from the slider horizontally when the shaft is vertical and the slider is on the same vertical alignment (as per an in-line slider mechanism). The input shaft rotates clockwise at a fixed 600 revolutions per minute.

The rocker is to be connected to the slider and needs to be designed such that the end moves in a 2m radius curve through an angle of +/-30°. Refer figure 1.

Give a complete analysis of the systems translational and rotational velocities, accelerations and positions of all components. Detail in a report all assumptions and relevant information about the system. Give a complete detailed understanding of system.

Part B) Vibrations and dampeners

A mass of 10kg is suspended on a spring and is it found that when it oscillates the amplitude reduces to 50% of the initial value after 5 oscillations over a period of 3 seconds. Design a dampener such that the amplitude reduces to 10% of the initial after 2 oscillation with the same initial frequency.

Detail in a report all assumptions and relevant information of the system. Give complete detail understanding of system.

This assignments part A & B must be presented as a formal methodical report with clear unambiguous references. All calculations and assumptions must be provided together with a full explanation of all the terms used - equations have to be typed. This assignment must be typed be in Microsoft Word format or as a PDF and submitted via DSO. No hand written, hand submitted or non-conforming assignments as outlined above will be accepted. Extensions will only be granted if asked for in writing (email) three days before the due date; a maximum of 7 days will be granted if circumstances are valid. Students can only ask for one extension for the trimester period - thus if you have an extension for assignment one you are not able to have another extension for assignment 2 unless under very exceptional circumstances.

Assessment will be returned in approximately two weeks and will be in the form of the rubric below, comments where appropriate and with an associated letter grade eg HD, D, P etc.