Variable Stiffness Actuation for Bioinspired Underwater Propulsion

This project aims to study the use of Variable Stiffness Actuators (VSA) embedded in aquatic propulsors to ensure persistent operation at maximum propulsive efficiency.
Description of the Project: 

Fish and other aquatic organisms propel themselves via flapping foil. Similarly, aquatic organisms such as squids and octopuses perform pulsation of a hollow, flexible chamber of their body in order to recursively ingest and expel fluid and in this way perform a pulsed-jetting locomotion routine. In order to enhance swimming efficiency, many aquatic organisms exploit resonance-based phenomena where activation frequency and natural frequency of the system (combined fluid and body) are matched.

This project aims to study, design and test Variable Stiffness Actuators (VSA) embedded in aquatic propulsors with the aim of actively selecting the degree of flexibility of the system and in this way exploit resonance-aided actuation over a continuous spectrum of frequencies. The purpose of this is to enable an underwater vehicle endowed with such VSA apparatus to always operate near the resonance regime and in this way benefit of persistent maximum efficiency over a broad range of swimming speeds.

Project number: 
140029
First Supervisor: 
University: 
University of Edinburgh
Second Supervisor(s): 
First supervisor university: 
University of Edinburgh
Essential skills and knowledge: 
Strong mechanical/mechatronics background with excellent design and manufacturing skills
Desirable skills and knowledge: 
An inclination for dynamics/control and fluid-mechanics would be advantageous
References: 
  • F Giorgio-Serchi, A Lidtke, G Weymouth, (2018), A soft aquatic actuator for unsteady peak power amplification, IEEE/ASME Transactions on Mechatronics, DOI: 10.1109/ TMECH.2018.2873253
  • S. Wolf et al., "Variable Stiffness Actuators: Review on Design and Components," in IEEE/ASME Transactions on Mechatronics, vol. 21, no. 5, pp. 2418-2430, Oct. 2016. doi: 10.1109/TMECH.2015.2501019