Page 314 - Handbook of Biomechatronics

306 Andres F. Ruiz-Olaya et al.

and standing. This electrical stimulation is known as functional electrical
stimulation (FES). Hybrid systems incorporating exoskeletons with other
technologies such as FES have been reported in the literature (del-Alma
et al., 2014). Hybrid actuation and control have a considerable potential
for walking rehabilitation, with adequately control strategies of hybrid
systems that command FES and robotic controllers.

4.1.2 Nonmedical Applications
Currently, wearable robotics designed to be part in an industrial setting is the
fastest growing field of exoskeleton research. Exoskeletons for industry and
the workplace offer three main advantages: reduction in work-related
injuries, saving billions of dollars in medical fees, sick leave, and lawsuits.
Exoskeleton has lowered worker fatigue, leading to increased worker alert-
ness, productivity, and work quality. It has the ability to keep quality and
experienced personnel past their physical prime in the work force longer.
In addition of using exoskeletons for the human motor performance of
soldiers, the military are looking to build VR simulators for troop training
(e.g., firing a cannon). Exoskeletons have been envisioned to support this
kind of training.
Other future applications of exoskeletons focus on gaming. There are
commercial organizations aimed to develop a full exoskeleton that is
suspended in the air and provide the appropriate resistance to make the user
feel they are walking, swimming, or interacting with objects. For example,
to swing a virtual axe, the player will have to feel resistance at the hands via a
glove-type exoskeleton. Currently, gaming exoskeletons do not aim to sim-
ulate entire objects but just their effects. If a gamer is playing a first-person
shooter then a vest could compress to simulate the player being hit.

4.2 Technologies
Technologies are in most instances the limiting factor in developing new
exoskeletons. Exoskeletons for portable and ambulatory applications are
limited in the literature, one of the reasons being a lack of enabling technol-
ogies. Ambulatory scenarios require miniaturized, robust, and energetically
efficient technologies, for example, control, sensors, and actuators. Chal-
lenges and trends of technologies for exoskeletons can be split up into a
generic categorization applicable for any mechatronic system: a signal
domain (e.g., controllers, sensors); energy domain that includes the source
of energy and the conversion into mechanical power that is applied through