PhD position: Additive manufacturing of soft electroactive polymer actuators for high optical quality mirrors (INSA Lyon - LGEF)

Topic description

Project context

The Live-Mirror project is an interdisciplinary and international project received for European funding from EIC Pathfinder 2022. This project aims to develop a new technology for large-area mirrors of high optical quality while minimizing mass. The combination of electroactive materials, additive manufacturing and glass slumping methods opens the way to a new generation of “Live” mirrors that can be deformed in real time in order to compensate the local deformations of the optical surface. We expect that our mirrors should be produced at a savings of at least one order of magnitude over present cost. Creating addressable stiffness for a thin glass – The deformation of any optical system due to variable gravity and/or wind loads must be either mitigated with a stiff opto-mechanical structure or shaped actively to correct the deformations. For systems larger than just a few meters, using mass alone to achieve the passive stiffness needed for diffraction-limited optics is not practical − the 10m Keck telescopes exceed this limit and depend on active electromagnetic mirror surface shape control. The Live-Mirror Solution to this problem is to correct the deformation of the optics as it responds to the changing gravity and/or wind loads. Our aim is to demonstrate that a sufficiently thin glass sheet (as thin as a few mm) can be deformed and supported using a novel lightweight hybrid structure based on electroactive polymers (EAPs) deposited by additive manufacturing techniques. These tailored-made EAPs should deliver controlled electrostatic energy exceeding the gravitational, wind loads and thermal deformation energy of the glass sheet.

Research objectives of the PhD

The goal of the PhD is to develop and characterize a dynamic hybrid meta-materials structure (HM-MS) by sandwiching a thin glass (fire-polished) and a reaction surface filled by lattices of Electroactive polymer (EAP) based force-actuators and -sensors in series via additive manufacturing. This will create a novel hybrid meta-material with superior stiffness-to-density-ratio properties. Filling this sandwich of slumped glass surfaces (optical and reactive surface) it will allow to develop a deterministically distributed lattice of EAP-based force-actuators in series with force-sensors interconnected by flexible electronics and via additive manufacturing in the backside of the optical surface. The EAP force actuators volume (thickness, shape), material and distribution (spatial resolution/pitch size) will be determined/optimized by the dynamic range of the actuators and multi-sensing close-loop calibration metrology system to correct the “shape-errors” with an imposed actuator force distribution. Correcting the shape-errors means “touching” the backside of the optical surface (OCS/FPS) via one-pass, predictable and punctually “electronic polishing” as it responds to (i) environmental changes such due to gravity and/or wind loads and (ii) to achieve diffraction limited operation. The distributed lattice would take several pitch sizes, layers and distributions that will depend on the actuators/sensors dynamics of corrections/sensing.

About PhD candidates and application information

• You are a graduated engineer or master in materials science or applied physics, or chemistry, electrical or mechanical engineering with a curiosity for new technologies.

• You have a skill in multi-physics coupling, a good practical sense and knowledge and understanding of technological processes.

• Knowledge in polymer physics and/or additive manufacturing would be helpful.

• You are recognized for your autonomy, your curiosity, your versatility and your ability to learn.

• You are able to develop quality relationships for the benefit of the advancement and progress of the activity at the internal level.

• Due to the international consortium of the Live-Mirror Project, high English skill (both written and spoken) is required.

Offer and benefits

Contract of 36 months – full time (starting 2023)

Gross monthly salary: 2120€ : 25k€ /year (monthly net salary ~1650 €)

Paid leave: 42 days per year

Staff restaurant

50% reimbursement of public of transport costs

Number of holidays: 42 days per year

Social, cultural and sport events and activities

Access to professional training

Health insurance

Funding category

Funding further details