Difference between revisions of "Team F"

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(Design Development)
(Design Development)
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Score: .268.
 
Score: .268.
  
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[[File:Selected from the 1st set of trials.png]]
  
Middle Bar Test 2 provided the lowest score and became the base model for step 2, which was to cut out a substantial, trapezoidal section near the applied force. An additional trapezoidal section was  
+
Middle Bar Test 2 (above) provided the lowest score and became the base model for step 2, which was to cut out a substantial, trapezoidal section near the applied force. An additional trapezoidal section was  
 
added towards the top of the arm as well.  Each of the Cut Tests we performed involved different arrangements and sizes of the trapezoidal cuts.
 
added towards the top of the arm as well.  Each of the Cut Tests we performed involved different arrangements and sizes of the trapezoidal cuts.
  
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Score: .199
 
Score: .199
  
File:Selected from the 2nd set of trials.png]]
+
[[File:Selected from the 2nd set of trials.png]]
  
 
Cut Test 3 (above) provided the lowest score and was used as the base model for the step 3, where we tested different depths of shelling.
 
Cut Test 3 (above) provided the lowest score and was used as the base model for the step 3, where we tested different depths of shelling.

Revision as of 16:48, 26 September 2012

Members

Preliminary Designs

Team Fα

Team members: Isaac, Christine, Lindsay

Team Fα's initial design involved several triangle cut-outs across the robot arm template. The triangles would provide support to the arm while removing much of the extraneous mass. The results of this design were as follows: Volume: .88; Displacement: .3653; Score: .3214.

Team Alpha's Initial Design Alpha group initial design.png

Team FΩ

Team members: Greg, Andrew

The premise of Team FΩ's design was to do away with extraneous portions of the given design. The result was a curved, s-shape piece that cut off the portions past the pre-cut notches under the hypothesis that these areas did not help the piece resist deformation. The curved structure was intended to eliminate the corners created by the notches so that stress could not focus on any particular spot. The results for this initial design are as follows: Volume: .90; Displacement: .27; Score: .243.


Omega Group's Initial Design Omega group Initial Design.png

Synthesis of Designs

The team decided to base the final design primarily on Team Fα's preliminary design because it performed better with virtually the same volume. The main quality that we tried to incorporate into our new design was the use of triangles in the central region of the piece, between each of the notches. We also cut away the portions past the notches, like in Team FΩ's design.

Design Development

Step 1 was to find the ideal arrangement and orientation of two triangle cuts in the center of the arm.

Middle Bar Test 1: Displacement: .298; Volume: .95 in^3; Score: .280.

Middle Bar Test 2: Displacement: .2922; Volume: .95 in^3; Score: .277.

Middle Bar Test 3: Displacement: .2682; Volume: .95 in^3; Score: .255.

Middle Bar Test 4: Displacement: .2824; Volume: .95 in^3; Score: .268.

Selected from the 1st set of trials.png

Middle Bar Test 2 (above) provided the lowest score and became the base model for step 2, which was to cut out a substantial, trapezoidal section near the applied force. An additional trapezoidal section was added towards the top of the arm as well. Each of the Cut Tests we performed involved different arrangements and sizes of the trapezoidal cuts.


Cut Test 1: Displacement: .358 Volume: .7 in^3 Score: .250

Cut Test 2: Displacement: .29 Volume: .72 Score: .209

Cut Test 3: Displacement: .277 Volume: .72 Score: .199

Selected from the 2nd set of trials.png

Cut Test 3 (above) provided the lowest score and was used as the base model for the step 3, where we tested different depths of shelling.


Shelling Test 1: Displacement: .4195 Volume: .50 Score: .210

Shelling Test 2: Displacement: .323 Volume: .61 Score: .197

Selected from the 3rd set of trials.png

Shelling Test 2 (above) provided the best score despite being only marginally better than the score without any shelling at all. The small difference was still desirable, so Shelling Test 2 provided the base for the fourth and final step: lightening holes and filleting.


Lightening Holes and Filleting Test 1: Displacement: .3339 Volume: .59 Score: .196

Lightening Holes and Filleting Test 2: Displacement: Volume: Score:

Final Design

After testing the different cuts, shelling, and filleting options that were possible, we realized that the ultimate design included rounded edges. We kept the triangle and trapezoidal cut-outs in the center of the arm, but we filleted every edge possible on the inside and outside edges. We also added lightening holes through the sides to reduce the mass as much as possible while maintaining the same low displacement value.