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Biologically Inspired Robotics
13.1 Introduction
With aging comes various types of physical deterioration, which often affects
mobility. The muscular strength of older people may decrease and they may
be unable to walk or lose their stability during walking. Without appropriate
exercise and rehabilitation, their muscles will further deteriorate and they
may become bedridden. It has been found that exercise training can increase
strength and may improve motor activity in people with cerebral palsy (CP)
without adverse effects (Damiano et al. 2000). It was also demonstrated that
exercise increases the strength of affected major muscle groups in stroke survivors (Teixeira-Salmela et al. 1999). Therefore, an effective way to relieve
these problems and enable older people to fulfill their activities of daily living is to provide a means for them to be able to continue walking.
Assistive knee braces are a species of wearable lower extremity exoskeletons.
Such assistive equipment can enhance people’s strength and provide desired
locomotion and have advantages over wheelchairs, which are commonly used
for patients with mobility disorders. For example, assistive knee braces could
help the wearer walk on his or her own legs and therefore exercise the own
lower body. Moreover, it is possible to use this kind of lower extremity exoskeleton to assist older or disabled people to improve their mobility in order to solve
many daily life problems, such as going up and down stairs and over obstacles.
Some research groups have developed several wearable assistive knee
braces for walking support. The Berkeley Lower Extremity Exoskeleton
(BLEEX) was developed (Kazerooni and Steger 2006) to support a human’s
walking while carrying a heavy load on his or her back. The Hybrid
Assistive Limb (HAL; Kawamoto and Sankai 2002) was developed to
help people walk, climb stairs, and carry things around. The RoboKnee
(Pratt et al. 2004) provides assistance in climbing stairs and bending
the knees while carrying a heavy load. The Wearable Walking Helper
(WWH; Nakamura, Saito, and Kosuge 2005) and Walking Power Assist
Leg (WPAL; F. Chen et al. 2007) were designed to augment human power
during walking based on human–robot interactions. Some companies,
including Honda, have also developed assistive walking devices to support bodyweight and reduce the load on the wearer’s legs while walking,
climbing stairs, and in a semi-crouching position (Honda 2008).
All of the above assistive knee braces use powerful actuation devices
to provide adequate supporting torque as well as smooth locomotion. To
assist the wearer in various postures and prevent knee braces from exceeding the restricted motion, actuators that function as a brake/clutch combined with the ability to safely interlock are desirable. Power consumption
by the actuation devices is another consideration in lengthening the working time of batteries after they are fully charged. Therefore, well-designed
actuators would be the key component for assistive knee braces in terms of
performance and safety.
Biologically Inspired Robotics
13.1 Introduction
With aging comes various types of physical deterioration, which often affects
mobility. The muscular strength of older people may decrease and they may
be unable to walk or lose their stability during walking. Without appropriate
exercise and rehabilitation, their muscles will further deteriorate and they
may become bedridden. It has been found that exercise training can increase
strength and may improve motor activity in people with cerebral palsy (CP)
without adverse effects (Damiano et al. 2000). It was also demonstrated that
exercise increases the strength of affected major muscle groups in stroke survivors (Teixeira-Salmela et al. 1999). Therefore, an effective way to relieve
these problems and enable older people to fulfill their activities of daily living is to provide a means for them to be able to continue walking.
Assistive knee braces are a species of wearable lower extremity exoskeletons.
Such assistive equipment can enhance people’s strength and provide desired
locomotion and have advantages over wheelchairs, which are commonly used
for patients with mobility disorders. For example, assistive knee braces could
help the wearer walk on his or her own legs and therefore exercise the own
lower body. Moreover, it is possible to use this kind of lower extremity exoskeleton to assist older or disabled people to improve their mobility in order to solve
many daily life problems, such as going up and down stairs and over obstacles.
Some research groups have developed several wearable assistive knee
braces for walking support. The Berkeley Lower Extremity Exoskeleton
(BLEEX) was developed (Kazerooni and Steger 2006) to support a human’s
walking while carrying a heavy load on his or her back. The Hybrid
Assistive Limb (HAL; Kawamoto and Sankai 2002) was developed to
help people walk, climb stairs, and carry things around. The RoboKnee
(Pratt et al. 2004) provides assistance in climbing stairs and bending
the knees while carrying a heavy load. The Wearable Walking Helper
(WWH; Nakamura, Saito, and Kosuge 2005) and Walking Power Assist
Leg (WPAL; F. Chen et al. 2007) were designed to augment human power
during walking based on human–robot interactions. Some companies,
including Honda, have also developed assistive walking devices to support bodyweight and reduce the load on the wearer’s legs while walking,
climbing stairs, and in a semi-crouching position (Honda 2008).
All of the above assistive knee braces use powerful actuation devices
to provide adequate supporting torque as well as smooth locomotion. To
assist the wearer in various postures and prevent knee braces from exceeding the restricted motion, actuators that function as a brake/clutch combined with the ability to safely interlock are desirable. Power consumption
by the actuation devices is another consideration in lengthening the working time of batteries after they are fully charged. Therefore, well-designed
actuators would be the key component for assistive knee braces in terms of
performance and safety.