The semi-active controllers considered in this study were: ICOO – integral controller with an on-off algorithm;
LQRCOO and LQR2COO – linear quadratic regulators with an on-off algorithm; MPCCOO – Model predictive
controller with an on-off algorithm. These controllers are of the force feedback type, which use a linear controller to
calculate a desired force fd, using the feedback information (measured responses), which is then used to compute
(algorithm) the input voltage V of the device using the feedback information of the device (measured force). The
following sub-sections describe the SA controllers