This is the mock up version for the spine of our robot fish. It's design was derived from Poly I and it's dimensions are; 16 inches long, 4 inches tall, and 3.6 inches wide. Spine was built by cutting and drilling holes in to lexan, a flexible polymer. The bulkheads were manufactured using the laser cutter in the ME materials lab, 7th floor. Tendons were made using dental floss. Handles were made by looping the dental floss so it would not slip out of or dig into our hands. While bend angle was satisfactory as expected, we still need to find ways to make the spine less stiff. Possible solutions would be to cut lexan narrower or to use more flexible material. We acknowledge Joe for helping us using the laser cutter.