CONCEPTUAL MODEL
Identify the problem -
The scenario given is to generate a truss like tower using limited materials, time, and other constraints/criteria. This tower should be made using only balsa wood and glue and is to be tested for most efficiency, based off the amount of weight it can hold.
Generate Ideas -
- One idea is to use vertical beams opposed to horizontal as the stress point we felt would be smaller
-Another idea was to make a pyramid like design that we thought would work because we see real life examples like in Egypt which hold TONS
-One idea that was based off modern buildings was to have four walls opposed to three as it will split the load to more areas and is based off more modern structures we see
-Another idea was to use a two layer design that will help reinforce the tower in order to increase the towers limit to hold weight
-Another idea was to base it off a barrel design that adds support to where the stress points are
Constraints -
- Materials: Balsa Wood, Glue,foam board, and wax paper
- Size Restraints: Minimum size is 2" x 2" x 3" and maximum size is 4" x 4" x 5"
- The amount of class time we had to build the structure
- The tower must fit inside the bin provided to keep our tower after school
- The tower must be made to work with stress analyzer, which is done by having a hole through the design
- Tools: Our bare hands and sandpaper, we are restricted from using scissors or anything else to manipulate the balsa wood
Criteria -
-Efficient(Holds an adequate amount of weight for the amount of material used)
-Appearance(Design has eye appeal)
-Reproduction(Easy to remake)
-Least Deflection(Design is created smoothly)
Research -
Theoretical Research -
I have looked up many different professional builds and the basis for how they distribute weight and prevent stress on the lower tier of a design. Research shows that walls collapse when gravity is not pulling their weight towards the ground and instead is displaced towards a different direction. Research also shows that for a building to support its own weight more lightweight material is used at the top, then at the bottom where reinforced steel beams may be used instead of regular steel beams. Building design is also based off having very critical points in a structure called load bearing walls which if broken will leave part of a building to collapse which we know is not good.
google> how towers distribute weight
google>science behind modern buildings
http://www.explainthatstuff.com/howbuildingswork.html
http://science.howstuffworks.com/engineering/structural/skyscraper1.htm
http://ignoringfriction.blogspot.com/2008/12/skyscraper-structural-support-what.html
Empirical Research -
I have been in situations which you can see what ever side has the most weight acting on it will give like on a see saw. That basic law helped play into our build by the way we evenly distributed the weight so one side did not give before any of the others. I also have seen situations like a boxing match where someone bigger or in a heavier weight class can take more punches than someone in a lighter weight class. This can also be put towards how using more beams together will create a stronger design. One last thing I've noticed is that it is much harder to snap a short piece of balsa in half then a long one, this simple law played into us building a much smaller compact design.
Possible Solutions -
1) Wall Consisting of Two Layers of Vertical Balsa Beams 3" Tall With Base:
- This idea is based off of the idea, bigger, better, stronger. Simply meaning that the more balsa used will work together to hold a greater load and will also distribute the weight of the stress analyzer better which will be very keen in making a good design.
2) Tower With Four Beams in Each Corner With Diagonal Support Beams 3" High With a Base
- This idea is based off the previous idea. The walls between the four corner beams were taken out with the idea that the support beams can help the corner beams support the load and it would be more efficient than the previous idea. By using balsa to reinforce only the more stress oriented points and therefore using less balsa in the process. Also, this design stays truer to the Truss style that this project is supposed to be based on. The base in this solution serves the same purpose as the base in the previous solution.
Idea Matrix -
Identify the problem -
The scenario given is to generate a truss like tower using limited materials, time, and other constraints/criteria. This tower should be made using only balsa wood and glue and is to be tested for most efficiency, based off the amount of weight it can hold.
Generate Ideas -
- One idea is to use vertical beams opposed to horizontal as the stress point we felt would be smaller
-Another idea was to make a pyramid like design that we thought would work because we see real life examples like in Egypt which hold TONS
-One idea that was based off modern buildings was to have four walls opposed to three as it will split the load to more areas and is based off more modern structures we see
-Another idea was to use a two layer design that will help reinforce the tower in order to increase the towers limit to hold weight
-Another idea was to base it off a barrel design that adds support to where the stress points are
Constraints -
- Materials: Balsa Wood, Glue,foam board, and wax paper
- Size Restraints: Minimum size is 2" x 2" x 3" and maximum size is 4" x 4" x 5"
- The amount of class time we had to build the structure
- The tower must fit inside the bin provided to keep our tower after school
- The tower must be made to work with stress analyzer, which is done by having a hole through the design
- Tools: Our bare hands and sandpaper, we are restricted from using scissors or anything else to manipulate the balsa wood
Criteria -
-Efficient(Holds an adequate amount of weight for the amount of material used)
-Appearance(Design has eye appeal)
-Reproduction(Easy to remake)
-Least Deflection(Design is created smoothly)
Research -
Theoretical Research -
I have looked up many different professional builds and the basis for how they distribute weight and prevent stress on the lower tier of a design. Research shows that walls collapse when gravity is not pulling their weight towards the ground and instead is displaced towards a different direction. Research also shows that for a building to support its own weight more lightweight material is used at the top, then at the bottom where reinforced steel beams may be used instead of regular steel beams. Building design is also based off having very critical points in a structure called load bearing walls which if broken will leave part of a building to collapse which we know is not good.
google> how towers distribute weight
google>science behind modern buildings
http://www.explainthatstuff.com/howbuildingswork.html
http://science.howstuffworks.com/engineering/structural/skyscraper1.htm
http://ignoringfriction.blogspot.com/2008/12/skyscraper-structural-support-what.html
Empirical Research -
I have been in situations which you can see what ever side has the most weight acting on it will give like on a see saw. That basic law helped play into our build by the way we evenly distributed the weight so one side did not give before any of the others. I also have seen situations like a boxing match where someone bigger or in a heavier weight class can take more punches than someone in a lighter weight class. This can also be put towards how using more beams together will create a stronger design. One last thing I've noticed is that it is much harder to snap a short piece of balsa in half then a long one, this simple law played into us building a much smaller compact design.
Possible Solutions -
1) Wall Consisting of Two Layers of Vertical Balsa Beams 3" Tall With Base:
- This idea is based off of the idea, bigger, better, stronger. Simply meaning that the more balsa used will work together to hold a greater load and will also distribute the weight of the stress analyzer better which will be very keen in making a good design.
2) Tower With Four Beams in Each Corner With Diagonal Support Beams 3" High With a Base
- This idea is based off the previous idea. The walls between the four corner beams were taken out with the idea that the support beams can help the corner beams support the load and it would be more efficient than the previous idea. By using balsa to reinforce only the more stress oriented points and therefore using less balsa in the process. Also, this design stays truer to the Truss style that this project is supposed to be based on. The base in this solution serves the same purpose as the base in the previous solution.
Idea Matrix -
Summary -
In the end, we picked the Tower With Four Beams in Each Corner With Diagonal Support Beams 3" High With a Base. This was not just because it received a higher score in the idea matrix especially with it being so close. This idea was chosen because we knew pound for gram that it would hold more. Also the design we chose could be seen as more realistic to modern buildings as you wont really see a building with huge walls leaving no area on the floors. Another factor that played into the design we chose was time as it would have taken a lot more beams and time to produce the first option.
GRAPHICAL MODEL
*Black Pen was used to make top view definition easier
In the end, we picked the Tower With Four Beams in Each Corner With Diagonal Support Beams 3" High With a Base. This was not just because it received a higher score in the idea matrix especially with it being so close. This idea was chosen because we knew pound for gram that it would hold more. Also the design we chose could be seen as more realistic to modern buildings as you wont really see a building with huge walls leaving no area on the floors. Another factor that played into the design we chose was time as it would have taken a lot more beams and time to produce the first option.
GRAPHICAL MODEL
*Black Pen was used to make top view definition easier
MATHEMATICAL MODEL
Analyze -
The data presented in the graph demonstrates multiple trends and ideas. These trends include that the more weight the tower was the more weight it could hold which is based off class data we took. Another trend is that the shorter your tower is the more weight you can hold which is seen with those closer to the minimum height holding more weight. One other trend seen is the higher someones build quality the more weight it held. Now, this is very opinionated data but if you're more confident in your tower than others than I believe you'll probably do better.
Adjust -
Now looking back at my tower I probably would not change much other than increasing the towers weight and putting those extra balsa pieces to reinforcing stress points on the tower. The other trends would not really play into readjusting the design as we actually built ours at those peak conditions seen in the data(height and build quality).
Pictures
Analyze -
The data presented in the graph demonstrates multiple trends and ideas. These trends include that the more weight the tower was the more weight it could hold which is based off class data we took. Another trend is that the shorter your tower is the more weight you can hold which is seen with those closer to the minimum height holding more weight. One other trend seen is the higher someones build quality the more weight it held. Now, this is very opinionated data but if you're more confident in your tower than others than I believe you'll probably do better.
Adjust -
Now looking back at my tower I probably would not change much other than increasing the towers weight and putting those extra balsa pieces to reinforcing stress points on the tower. The other trends would not really play into readjusting the design as we actually built ours at those peak conditions seen in the data(height and build quality).
Pictures
Weight of Tower- Weight Held
Tower Height - Weight Held
Weight Held- Build Quality
WORKING MODEL
Progress
As any builder will tell you to start building you must generate an idea and that is exactly what we did. This idea generation can be seen in our conceptual model above, but we used the criteria and constraints we knew of to come up with ideas that we thought were the best and were based off research we found online. After we had chose an idea we soon started to sketch our idea which can be seen in the graphical model above. We then took this sketch and placed it between a piece of foam board and wax paper. This allowed us to use the sketch as a way to mark exact lines on the balsa in order to produce an exact model of our drawing. We simply marked lines on the balsa and started sanding down and creating the beams we needed to complete one side at a time. Once these side were completed we started adding the beams need to reinforce our structure and that would complete our tower itself and we then constructed a base that left a hole in the bottom measuring 0.75" by 0.75".
Pictures -
Progress
As any builder will tell you to start building you must generate an idea and that is exactly what we did. This idea generation can be seen in our conceptual model above, but we used the criteria and constraints we knew of to come up with ideas that we thought were the best and were based off research we found online. After we had chose an idea we soon started to sketch our idea which can be seen in the graphical model above. We then took this sketch and placed it between a piece of foam board and wax paper. This allowed us to use the sketch as a way to mark exact lines on the balsa in order to produce an exact model of our drawing. We simply marked lines on the balsa and started sanding down and creating the beams we needed to complete one side at a time. Once these side were completed we started adding the beams need to reinforce our structure and that would complete our tower itself and we then constructed a base that left a hole in the bottom measuring 0.75" by 0.75".
Pictures -
Redesign/Revisions
The only revisions I would've made on our design was to add more braces at stress points. The aftermath of our test showed us where the tower broke and feel reinforcing those point with balsa to prevent bending would've allowed us to hold more weight. But, I truly feel that our design was very good and used a great amount of research.