8.1 - Project Proposal
Project Proposal
Mechanism-Assisted Rowing Boat
Introduction
Human-powered boats rely on repetitive rowing motions to generate thrust and move through water. However, traditional rowing can be inefficient because the user must coordinate complex motions while applying force throughout the stroke. This often results in inconsistent force output and wasted energy.
Mechanical linkages can convert simple input motions into controlled motion profiles that improve efficiency. This project proposes a boat propulsion system powered by a four-bar slider-crank mechanism. The mechanism will convert rotational input into reciprocating motion that drives a paddle through the water, producing forward thrust while increasing mechanical advantage during the rowing stroke.
Problem Statement
Effective rowing requires a coordinated motion that applies force to the water during the power stroke and quickly returns the oar to its starting position. This creates a complex motion and force profile that can be difficult for a user to maintain consistently.
Without mechanical assistance, the rower must supply both the motion and force needed to propel the boat, which limits efficiency and consistency. A mechanism capable of generating a controlled reciprocating motion could regulate the rowing stroke and improve propulsion performance.
Mechanism
The proposed system uses a four-bar slider-crank mechanism, consisting of a rotating crank, connecting rod, slider, and frame. This mechanism converts continuous rotational motion into linear reciprocating motion.
In this design, the user will rotate a crank or pedal. The crank drives the connecting rod, which moves the slider back and forth. This reciprocating motion will be transferred to a paddle that moves through the water to generate thrust.
By selecting appropriate link lengths, the mechanism can increase mechanical advantage during the power stroke, producing greater propulsion force while maintaining a smooth and repeatable rowing motion.
Proposed Scope of Work
The project will involve designing, analyzing, and building a prototype of the mechanism-assisted rowing system. First, the team will perform basic kinematic analysis to determine suitable link dimensions and motion characteristics. A kinematic diagram and degree-of-freedom analysis will also be developed.
Next, a prototype mechanism will be constructed and integrated with a small boat model or testing platform. Finally, the system will be tested to observe the motion of the mechanism and evaluate its ability to generate propulsion.
Manufacturing will primarily be 3D printed and laser-cut parts. Our goal is to make not only a functioning mechanism but also a piece of artwork that showcases not only our own artistic skill but also props up those who have come before us and the many, many engineers of the ancient world who designed these ships (without any CAD too).
Electronics will include a motor, a battery, and a switch. We are deciding between a servo motor or a DC motor. A servo might give us more force if our mechanism needs it, but a DC motor would make the electronics simpler. Stretch goals include adding a microcontroller and LED lights to simulate Greek fire being thrown from the ship with burning sound effects, flashes of green, and the waves crashing with flashes of blue and sea sounds.
Preliminary Design
