ProtoDUNE is a 770 ton liquid argon detector being constructed at CERN as a test-bed for the huge DUNE experiment, a billion dollar international neutrino experiment in which a beam of neutrinos will be fired from Fermilab, USA to a 10 kton liquid argon detector in the Homestake mine, S. Dakota. This project will focus on optimization of the central Anode Plane Array (APA) detectors that are key to ProtoDUNE and are being built by Sheffield with other groups. The project involves finalising design of the APAs, developing simulations of the final detector and then analysis of particle beam data with a view to aiding the final design of DUNE itself. This includes study of electron lifetime performance and low energy performance. There will be opportunity for involvement in installation and operations of ProtoDUNE at CERN and a chance for long term attachment at CERN (6-12 months).