vibration , Other Engineering

Assignment Help:
ME 312 Project: Design for Vibration and Shock Suppression (Due Sunday 6/5/2012)

Introduction

To protect the electronic control module from fatigue and breakage, it is desirable to isolate the module from the vibration or shock induced in the car body by road and engine vibration. See Figure 1.

(a)
Figure 1. A schematic vibration system.

Model
Model this module vibration isolation system as a single-degree-of-freedom spring-mass-damper system with a moving base (Figure 1-b,c). The module ’s mass can be taken to be 0.5 kg. The car body on which the isolator mounted is modeled as the moving base. The base is subjected to harmonic or shock displacement conditions, y(t). The displacement excitations of the base can be approximated as
(a) (for harmonic loading) y(t)=(0.01)sin(200 t).
(b) (for shock loading )
i. y(t)=0.025 sin(100*p t) m for 0 < t < 0.01sec
ii. y(t)= 0 for t > 0.01 sec.

Objective and Constraints
Design a vibration and shock isolation systems (choose the parameters k and c for each system) to minimize module’s maximum displacement when subjected to the prescribed vibration and shock base excitation. Your design must also satisfy the following constraints:
(1) The maximum acceleration experienced by the hard drive should be less than 11g’s (g=9.8 m/s2) .
(2) Module’s static deflection (downward deflection caused by module weight) is less than 0.0050 m.
(3) k and c must be within the following ranges: 300 = k = 3500 N/m and 1= c = 500 N.s/m. Select k and c from Ref 2 if applicable or from a manufacturer catalog. Both k and c are assumed constants working at room temperature of 25oC.

Presentation of Results
In your report, include a table with your design choices for k and c and the resulting values of maximum deflection, maximum acceleration and static deflection.
In addition, create and show the following plots:
(1) Displacement ratio (T.R.) versus frequency ratio for harmonic loading only (similar to Figure 2.13 of Ref. 1).
(2) Force transmissibility versus frequency ratio for harmonic loading only (similar to Figure 2.14 of Ref. 1).
(3) Maximum acceleration versus frequency ratio.
(4) The displacement (x(t))) versus time. Plot it for at least 4 periods of oscillation.
(5) Use two values below and two values above the value you chose in your design.
(6) Compare the selected values of k and c for both loading conditions(i.e. for harmonic loading and shock loading). Are they similar? Why?

References:
(1) Inman, D. J. Engineering Vibration, 3rd edition.
(2) Mechanical Properties of Rubber.








Related Discussions:- vibration

Jfet self biasing, VDD=20V,RG=1MOHM,RD=3.3KOHM,RS=1KOHM,IDSS=8MA,VP=-6V

VDD=20V,RG=1MOHM,RD=3.3KOHM,RS=1KOHM,IDSS=8MA,VP=-6V

Pattern practices, Pattern Practices : A pattern may be defined as a repli...

Pattern Practices : A pattern may be defined as a replica or fascimile model of the desired casting which, when packed or embedded in a appropriate moulding material, creates a ca

Fire fighting operations - high rise buildings, Fire fighting operations - ...

Fire fighting operations - high rise buildings: Inlets that allow the fire service to supplement to water to the sprinklers and to the fire mains are useful additions to the m

Dsp, Dit fft idft

Dit fft idft

Gutter fill, calculations about gutter fill?

calculations about gutter fill?

Cash mangement, how to do a cash management project report ,including probl...

how to do a cash management project report ,including problems?example?

Pysical chemistry , explain hydrogen bonding & impotents of it

explain hydrogen bonding & impotents of it

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd