University of Bath URSA project: Piezo pumps for high-bandwidth hydraulic actuation

This project is one of a number that are in competition for funding from the University of Bath URSA competition.

Project

Piezopumps provide an attractive alternative to traditional valve-controlled circuits for driving small actuators i.e. less than 100W. They provide the ability to distribute power electrically rather than hydraulically, which can bring both weight and efficiency savings, and improve reliability due to the lower number of moving components and the use of a solid-state drive element in the piezostack. In contrast to most hydraulic pumps, piezopumps can operate above 1kHz. This means the pump is capable of being the control member as well as the power source in high frequency control systems. This meets requirements in developing sectors, such as robotics and electric aircraft. It also offers potential cost savings by further reducing component count and, also, potential energy savings as only the flow required is generated. A standard valve system relies on generating excess power and then throttling down to the required level. A standard pump-controlled system can often fail to provide a sufficient dynamic response for good control behaviour. Piezopumps provide a best of both worlds with high bandwidth and reduced power. 

This project will develop upon a piezopump designed and built at the University of Bath. This will include further modelling of the high frequency reed valve, alongside investigations into expected improvements from the phasing of multiple pumping elements and novel methods of pre-loading the piezo stack. The performance of the pump will then be demonstrated in closed-loop control on a robotic arm.

An interest in, and experience with, mechatronic systems, fluid power and control systems would be of benefit.

The Centre for Power Transmission and Motion Control (CPTMC) at the University of Bath is a diverse and inter-disciplinary centre which co-hosts one of the top international conferences on Fluid Power. The CPTMC is based on the Claverton Down campus, overlooking the city of Bath, a world-heritage city, rich in culture.

Candidate Requirements

Applicants should hold, or expect to receive, a First Class or good Upper Second Class Honours degree (or the equivalent). A master’s level qualification would also be advantageous.

Non-UK applicants must meet our English language entry requirement by February 2023 in order to be considered for funding.

Enquiries and Applications

Informal enquiries are encouraged! Direct these to Dr Nathan Sell - N.P.Sell@bath.ac.uk

Please make a formal application should via the University of Bath’s online application form for a PhD in Mechanical Engineering

When completing the form, please identify your application as being for the URSA studentship competition in Section 3 Finance (question 2) and quote the project title and lead supervisor’s name in the ‘Your research interests’ section. 

More information about applying for a PhD at Bath may be found on our website.

Funding Eligibility

To be eligible for funding, you must qualify as a Home student. The eligibility criteria for Home fee status are detailed and too complex to be summarised here in full; however, as a general guide, the following applicants will normally qualify subject to meeting residency requirements:

• UK nationals (living in the UK or EEA/Switzerland)
• Irish nationals (living in the UK or EEA/Switzerland)
• Those with Indefinite Leave to Remain
• EU nationals with pre-settled or settled status in the UK under the EU Settlement Scheme.

This is not intended to be an exhaustive list. Additional information may be found on our fee status guidance webpage, on the GOV.UK website and on the UKCISA website.

Equality, Diversity and Inclusion

We value a diverse research environment and strive to be an inclusive university, where difference is celebrated and respected. We encourage applications from under-represented groups. In particular, we are welcoming applications from candidates with Refugee, Asylum Seeker, or Humanitarian Protection in the UK to our Doctoral Sanctuary Studentship in Engineering and Design.

If you have circumstances that you feel we should be aware of that have affected your educational attainment, then please feel free to tell us about it in your application form. The best way to do this is a short paragraph at the end of your personal statement.

The Disability Service ensures that individuals with disabilities are provided the support that they need. If you state if your application that you have a disability, the Disability Service will contact you as part of this process to discuss your needs.

Keywords: Control Systems; Fluid Mechanics; Integrated Engineering; Mechanical Engineering; Mechatronics; Robotics