Manta rays are known for their high efficiency, fast swimming speed, high manoeuvrability (e.g. turning on a dime), and great stability (even in a turbulent sea). Manta rays' pectoral fins play a key role in putting in such excellent swimming performance because of their enormous thrust generation capability. Pectoral fins of manta rays generate thrust for locomotion by oscillating dorsoventrally. Having dorsoventrally flat surface that pitches throughout upstrokes and downstrokes of the oscillation, they produce an anteriorly-directed lift force that yields a thrust vector for propulsion. The angle at which the lift force is directed towards the front is called angle of attack.
Pectoral fins of manta rays have been a great source of inspiration for propulsive mechanisms of underwater vehicles. We are developing an underwater vehicle that uses a fin mechanism design inspired by manta ray's pectoral fins for locomotion. The underwater vehicle has two pectoral fins, left and right; each of them is driven with electric motors. The underwater vehicle's body design is close to manta rays' body in terms of shape for hydrodynamic integrity.
This project aims to design and develop a flight control method for the underwater vehicle propelled by pectoral fin mechanisms emulating pectoral fins of manta rays. The flight control includes forward swimming, steering (to change swimming direction), and diving/heaving (to swim at different depths). Our approach to the flight control is to use the thrust forces generated by the pectoral fins on each side of the vehicle for producing different manoeuvres.
One of the main factors governing these oscillatory fins' thrust generation could be the waveform of the oscillation. It can be defined as the angular position of the fin or its tip's traveling distance in each oscillation cycle. Stroke frequency and stroke amplitude are the other two factors. These factors can affect the magnitude of the lift generated and the angle of attack, and thus, they affect the thrust generated.
In our underwater vehicle, for the flight control, the pectoral fins can oscillate independently with different stroke frequencies and stroke amplitudes. Besides, their neutral position (e.g. the horizontal position) can also be changed independently. In this project, these parameters can be used for the flight control. With these, we can generate different thrust forces at each side of the vehicle for different manoeuvres.
Applications close 5pm, Thursday 20 December, 2018.
This scholarship is available over 3 years.
- Stipend of $27,596 per annum tax exempt (2019 rate)
To be eligible you must:
- be a domestic candidate (domestic includes candidates with Australian Citizenship, Australian Permanent Residency or New Zealand Citizenship).
- meet Deakin's PhD entry requirements
- be enrolling full time and hold an honours degree (first class) or an equivalent standard master's degree with a substantial research component.
Please refer to the research degree entry pathways page for further information.
How to apply
Learn more about submitting a successful application on the How to apply page
For more information about this scholarship, please contact Dr Soheil Arastehfar
Dr Soheil Arastehfar
Email Soheil Arastehfar
+61 3 5227 3237