Fig. 1

General control scheme for an exoskeleton. The physical system in red is separated from the control by the dashed line. The control is divided into four hierarchical levels, with a few keywords to indicate their function. The thin lines represent data flow from the available exoskeleton sensors. The thick lines represent the control/decision commands to a lower control level. The assistance block in green transforms the sensor data to desired assistance in the low-level control block