Active Suspension Control for Improved Ride Comfort and Vehicle Performance Using HHO-Based Type-I and Type-II Fuzzy Logic

. 2025 Oct 7;10(10):673. doi: 10.3390/biomimetics10100673

Nomenclature
$m_{b}$	Mass of a quarter vehicle body
$m_{w}$	Mass of the wheel assembly
$k_{s}$	Spring coefficient of the suspension system
$b_{s}$	Damper coefficient of the suspension system
$k_{t}$	Spring coefficient of the tire
$b_{t}$	Damper coefficient of the tire
$x_{b}$	Body travel
${\ddot{x}}_{b}$	Body acceleration
$x_{w}$	Displacement of the wheel assembly
$x_{r}$	Road roughness (distortion)
$x_{b} - x_{w}$	Suspension deflection
$x_{w} - x_{r}$	Tire deflection
$F_{s}$	Actuator control force
$A S S$	Active Suspension System
$H H O$	Harris Hawks Optimization Algorithm
$T y p e I F u z z y$	Type I Fuzzy Logic
$T y p e I I F u z z y$	Type II Fuzzy Logic