Are you amazed by the fluid, efficient, and beautiful movement of fish in water? The secret to this movement lies in the ingenious coordination of their body, tail fin, and pectoral fins. One of the goals of modern biomimetic engineering is to simulate this biological movement using mechanical structures. Its core lies in converting rotational power (such as turning a handwheel) into periodic or undulating movements of specific parts (such as the fish's body, tail, and fins) through a transmission system composed of gears, chains, and linkages. Gears change the rotational speed and torque direction, chains transmit power over medium distances, and linkages convert rotational motion into reciprocating or oscillating motion along specific trajectories. When these mechanical components are precisely calculated and assembled, they work together to miraculously bring a model made of metal and engineering plastics to life, exhibiting swimming postures just like real fish. Our "Mechanical Fi
