High Fidelity Fast Simulation of Human in the Loop Human in the Plant (HIL-HIP) Systems

TL;DR

This paper presents a piecewise linear simulation method for human-in-the-loop systems with wireless networks, achieving over twice the speed of traditional nonlinear simulations while maintaining accuracy, demonstrated on a blood glucose control system.

Contribution

It introduces a formal analysis and a piecewise linear simulation framework for time-varying HIL-HIP systems, improving speed without sacrificing accuracy.

Findings

PLIS achieves >2.1x speedup over nonlinear simulation.

Formal analysis of time discretization impacts on accuracy.

Validated on an artificial pancreas system controlling blood glucose.

Abstract

Non-linearities in simulation arise from the time variance in wireless mobile networks when integrated with human in the loop, human in the plant (HIL-HIP) physical systems under dynamic contexts, leading to simulation slowdown. Time variance is handled by deriving a series of piece wise linear time invariant simulations (PLIS) in intervals, which are then concatenated in time domain. In this paper, we conduct a formal analysis of the impact of discretizing time-varying components in wireless network-controlled HIL-HIP systems on simulation accuracy and speedup, and evaluate trade-offs with reliable guarantees. We develop an accurate simulation framework for an artificial pancreas wireless network system that controls blood glucose in Type 1 Diabetes patients with time varying properties such as physiological changes associated with psychological stress and meal patterns. PLIS approach achieves accurate simulation with greater than 2.1 times speedup than a non-linear system simulation for the given dataset.