Finneas the Undulator

Introduction and Project Background

Simplifying the traditional undulating fin robot design by utilizing a central camshaft instead of a large number of servos

Explain project of mech design class — using a more mechanical-based model instead of servo-driven options

Moves in water and on land
- This is the main purpose of our project
- The fins allow for both thrust in water and rolling friction on land
Waterproof
- Electronics need a dry environment
Floats
- We want a surface-operating robot that doesn't need to adjust buoyancy
Looks swag and fishy

Tip of fins move 2 inches peak to peak
- Realistic distance we need the fin to move to generate enough thrust in water and enough distance to reach over obstacles on land
- The original goal was 4 inches but had to pivot due to geometric constraints. The fin rod pivot point must be at the hull/water interface and the hull must be a certain width for stability.
CAM follower moves 1 inch peak to peak
Camshaft rotates at 60rpm
- Creates a realistic and effective undulating frequency for water and land

Cam shaft
Cam geometry
- We chose a specific cam geometry to create the sinusoidal motion of the fins
Fin rod pivot geometry
- We designed a slotted hole for the pivot at the hull/water interface that restricts the vertical and horizontal translation of the fin rods while allowing to pitch back and forth
Follower to fin rod connection
- We decided to machine a halved pivot joint to connect the fin rods to the followers. This helps reduce our part count as we only need a bolt and nut to attach the two as opposed to some other specialized connector.
ESP for WiFi control

Two camshafts to allow for steering
More machined components to allow for higher torque
Sensors
Fin rod adaptations or additional tilt motors that allow it to work at different angles (such as pointing straight down for land movement or optimizing movement based on environment)
Non-PLA hull for better waterproofing
Fully enclosed hull to allow diving