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Thankfully, the dimensions of a standard 8 ounce reusable plastic bag are roughly 16.5 cm x 14.9 cm, which is a small enough size to be used with materials provided. Every part of our machine was designed with the reusable plastic bag's size in mind. The DC 12V 100RPM Gear Motor used for the joystick controlled robot in Build Exercise #1 was repurposed for the sake of the motor in our bag opening mechanism. A number of elements from previous Build Exercises were repurposed not only due to our group having some familiarity with the pre-existing elements, but reusing pre-existing elements also helped in keeping the overall cost of the mechanism down.
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