SEAN'S RC EXTRAVAGANZA
Analysis
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Under Construction
Analysis
Fig. 2 Chassis Deflection Analysis
According to a requirement set by the project team, the chassis of the car should not deflect more than 0.25 inches when dropped from a height of 2 feet. Figure A6 contains the analysis that was performed to determine if the selected material thickness would be appropriate to meet this requirement. A chassis thickness of 0.25 inches was used and a maximum deflection of 0.174 inches was found. Because 0.174 inches is less than 0.25 inches, this chassis thickness is more than adequate to help meet this requirement.
Using the information provided by the motor and battery manufacturers and the design parameters set by the project team, various analyses will be performed in order to ensure a safe design that will function and meet the requirements for the competition and design. In order to determine an adequate chassis thickness to meet the deflection requirement the team made, free body diagrams and beam deflection formulas were used. Using the weight of the motor and properties of 6061 aluminum, the minimum required thickness of the motor mount was determined with beam deflection formulas, meeting the requirement for the motor mount not to deflect more than fifty-thousandths of an inch. Using a free body diagram, equations of equilibrium, and the shear equation, the minimum required diameter for the pins of the front bumper were found.
Fig. 3 Minimum Thickness of Bumper Pin
Figure A11 contains the analysis that was performed to determine the minimum required thickness of the motor mount. Mechanics of materials and beam deflection equations were used to determine that a minimum thickness of 0.102 in is required. Using this and the standard aluminum sheet thicknesses, a standard thickness of 1/8” was used to make the motor mount.
Fig. 4 Minimum Thickness of Motor Mount
The analysis to determine the minimum thickness of the front bumper is in figure A12. A free-body-diagram and the shear equation were used to perform this analysis. The determined minimum thickness was 0.0063 inches giving a standard material thickness of 1/16” for sheets of polyurethane.