Complex three-link tail system design1 amplifies tail motion whilst minimis-
ing fish body motion, required for stable video stream
Forward kinematics method applied to design motion amplifying linkage.
Single motor used to entirely mimic fish swimming motions
1: Sayyed Farededdin Masoomi: Design, Fabrication, and Swimming Performance of a Free-Swimming Tuna-Mimetic Robot a Free-Swimming Tuna-Mimetic Robot
Kinematics
Robotic Fish
A custom PCB was manufactured for the electrical requirements:
Atmel microcontroller Required for hardware interrupts
PWM2 driver Servo & LED control
IMU3 Live pitch and roll update
Pressure sensor Live depth data
Motor driver Driver for tail linkage and buoyancy system
PCB Raspberry Pi 3 Model B A raspberry pi micro-computer was used as the main processor. This was essential for encoding the live video stream.
2: Pulse width modulation 3: Inertial measurement unit
Team members: Ben Fortune Mark Rayne Ben Mitchell Winston Poh
Director of Final Year Projects:
Dr. Mark Jermy
Client: Dr. Sharyn Goldstien (School of Biological Sci-ences, University of Canterbury) Supervisor: Dr. Stefanie Gutschmidt
Technicians: Julian Murphy, Garry Cotton Other University staff: Dr. Mark Jermy, Dr. Don Clucas, Julian Phillips, David Read Technical help: Nils Jensen
Problem Statement
The University of Canterbury's Department of Biological Sciences requires
an underwater vehicle to traverse the coastal waters of Kaikoura, to obse-
rve marine life with minimal disturbance to them. Water sample collection
is also a required feature.
Specification
Operation to depths up to 20 m underwater
Minimum 30 minutes operation on full charge
High resolution live video stream for navigation in highly turbid environ-
ment
Problem Statement
Peripheral driver circuit board Tail linkage
driver motor
RaspberryPi single-board computer
for data and video processing
Water sampling valves
Tail linkages
Pectoral fin
servos Depth control
syringe and motor
Rib-reinforced
silicone tail
Biomimetic Robotic Fish
Tether for real-time video stream-ing and control.
Two sampling vials
Up to 20m depth control
Up to 30 minutes operation on full charge
Solution
Li-Po batteries (rechargeable)
Camera and stabilizer servo
Design
Caudal Fin Pectoral Fins
Fish Head
Window
Electronics
