RC15DriveModule
The drive module consists of 3 integral components:
1) A drivetrain plate/mount
2) Motor
3) Omnidirectional wheel (omni wheel)
Background
The 2008 fleet of robots utilize a bull and pinion gear to transmit power to the omnidirectional wheels. Because of this arrangement
Pros:
Cons:
The 2011 fleet of robots utilize an internal ring gear and a spur gear to transmit power to the omnidirectional wheels. A standoff was also welded onto the drive module
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Cons:
Requirements
Prototypes
When performing injection molding, it is important to scale your CAD appropriately such that the shrink rate of the plastic is accounted for. Doing this will mean that the volume of the cavity of the mold will be larger than that of the desired component in CAD - however, once the part is molded and cools, it will ideally shrink to the correct size.
Thus, the team milled a test mold for the injection molding machine. This mold had a cavity about 1/8" deep, and was approximately 3" x 2", roughly the surface area of a credit card. This mold was used to mold a part and measure the shrink rate by simply looking at the percentage difference of the plastic part compared to the milled mold. Numbers are below:
Cavity width: 1.935"
Plastic part width: 1.871"
Estimated shrink rate: 3.3%
Rationale
Analysis/Performance
Prototype Notes:
