Engineering 25
Tutorial:
5 DoF, 3D
Analysis
Bruce Mayer, PE
Licensed Electrical & Mechanical Engineer
[email protected]
Engineering-36: Engineering Mechanics - Statics
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
Hanging Sign
 Determine the tensions in the
cables and the components of
reaction acting on the smooth
collar at G necessary to hold the
2000 N sign in equilibrium.
• The sign weight may concentrated
at the center of gravity.
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
𝑮𝒙 =
Engineering-36: Engineering Mechanics - Statics
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𝟑
𝟕
+
𝟒
𝟕
2000N
Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
Engineering-36: Engineering Mechanics - Statics
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
MATLAB CrossProd
 The Script-File Code
% Bruce Mayer, PE * ENGR36 * 19Jul12
%
ENGR36_H13_Tutorial_3D_5DoF_HangingSign
_1207.pptx
%
clear
clc
MagV = @(z) sqrt(dot(z,z))
AHv = [-2 2 1]
AHm = MagV(AHv)
uAH = AHv/AHm
EIv = [-2 2 -1]
EIm = MagV(EIv)
uEI = EIv/EIm
rGH = [0 2 4]
MAH = cross(rGH,3*uAH)
rGI = [0 2 -3]
MGI = cross(rGI,3*uEI)
rGW = [2 0 0.5]
uW = [0 -1 0]
Mw = cross(rGW,uW)
Engineering-36: Engineering Mechanics - Statics
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx
MATLAB Results
 For the Moment Cross-Prods
>> MAH = cross(rGH,3*uAH)
MAH =
-6
-8
4
>> MGI = cross(rGI,3*uEI)
MGI =
4
6
4
>> Mw = cross(rGW,uW)
Mw =
0.5000
0
-2.0000
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Bruce Mayer, PE
ENGR36_H13_Tutorial_3D_5DoF_HangingSign.pptx