3.5 KiB

Ideas taken from https://services.anu.edu.au/files/development_opportunity/ResearchProposalTips_0.pdf

Title / Topic

Research Problem (Justification)

  • Why does robust control exist
    • air conditioning example - but what if the plant is different? What is buddy leaves a window open
    • We can examine whether or not our controller (the ac unit) can handle the perturbed plant
    • We can know how open the window is before we have problems
    • We can guarantee this for this controller design and designed laws
  • So if we do this can be sure when we build the unit that this is how it will perform?
    • Well if it's controlled with a microcontroller or other code based solution, no.
    • The abstraction between the design and the finished controller destroys the guarantee
    • Things can happen in implementation that make the controller built not true to design
  • As a result, we need to reverify robustness on built controllers
    • This exists for structured perturbations. We

Gap In The Literature

Slide 1: Robust Control Foundations

Assertion: Robust control ensures stability despite system discrepancies.
Evidence:

  • Controllers are based on physical models that differ from real systems.
  • Robust control analyzes resilience to system perturbations.
  • Evolved from single-input single-output to multi-input multi-output systems.
    (Cite Doyle, Green, Brunton)

Slide 2: Structured vs. Unstructured Perturbations

Assertion: Robust control addresses structured and unstructured perturbations differently.
Evidence:

  • Structured: Based on physical tolerances (e.g., spring rates).
  • Unstructured: Accounts for unmodeled dynamics and broader uncertainties.
    (Diagram comparing structured and unstructured perturbations)
    (Cite Doyle, Green)

Slide 3: Disk-Based Unstructured Uncertainty

Assertion: Disk-based perturbation quantifies unstructured uncertainties.
Evidence:

  • Key equation: \tilde{P} = (1 + \Delta W_2) P
    • P: Nominal plant.
    • \Delta: Perturbation transfer function.
    • W_2: Uncertainty envelope.
  • Conditions for W_2 and \Delta:
    • \left| \frac{\tilde{P}(j\omega)}{P(j\omega)} - 1 \right| \leq \beta |W_2(j\omega)|
    • ||\Delta||_\infty \leq \beta.

(Include a visual of how \Delta affects P)


Slide 4: Current Limitations in Robust Control

Assertion: Current methods lack discrete examples of unstructured perturbations.
Evidence:

  • \Delta is undefined for experimental robustness verification.
  • Structured uncertainties are used experimentally but neglect unmodeled dynamics.
    (Cite Farzan, Hamilton)

Slide 5: Diffusion Models as a Solution

Assertion: Diffusion models can generate unstructured perturbations.
Evidence:

  • Forward process transforms data to Gaussian distribution.
  • Reverse process generates approximations of target data.
  • Applications in protein folding, training data generation.
    (Diagram of forward/reverse processes in diffusion models)
    (Cite Sohl-Dickstein, Abramson)

Slide 6: Parallels Between Diffusion Models and This Project

Assertion: Diffusion models address sparse perturbation generation in engineering.
Evidence:

  • Diffusion models create diverse training data from sparse sets.
  • Proposed approach: Generate unstructured perturbations from structured sets.
    (Illustration of sparse-to-diverse transformation concept)

Goals and Outcomes

Research Methodology

Metrics of Success

Risks and Contingencies