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- Want to achieve maximum torsional stiffness
- Decrease length of the beam, or increase the polar moment of inertia (increasing the diameter) of the material
- Get a balance between the weight and stiffness of the chassis
Round Vs. Square:
- Round tubing handles torsional stresses better than square tubing
- Square is easier to work with, align mounts, and jig up for welding
- Butt joints can be done on square tubing, and notching round tubing can be difficult
- Since the tubes for chassis will be professionally cut, notching does not present an issue
- Round tubing is therefore chosen
Triangulation:
- Triangulation of members is used to increase the torsional stiffness of the frame
- Each joint of the chassis should have at least three rods to complement the load path
- Thin walled tubing performs well in tension and compression, but poor in bending
- Triangulation helps mitigate this
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http://www.ijsr.net/archive/v4i4/SUB153824.pdf
http://mate.tue.nl/mate/pdfs/12814.pdf
http://www.altairuniversity.com/wp-content/uploads/2014/04/Ahmed-Oshinibosi.pdf