  Electric throttle valves represent a challenge for control design, as their
dynamics involve strong nonlinearities, characterized by an asymmetric
hysteresis. Carrying experiments on multiple valves, a large variability in the
characteristics of each valve and erratic steady-state behaviors can also be
noticed, impairing classical model-based control strategies. Nevertheless,
local data-driven linear models can be obtained and simple
proportional-integral (PI) controllers, tuned individually for each valve with
the appropriate data set, provide good tracking performance. As these
controllers cannot be transposed from one valve to another, a robust strategy
and an adaptive controller (using identification in closed-loop and controller
re-design) may be necessary to propose a general method. This work aims at
promoting control education on a simple yet challenging process, going from
frequency analysis and linear design to an adaptive control method implemented
with an online recursive algorithm.
