Review Article

Robotics in Lower-Limb Rehabilitation after Stroke

Table 1

Overview of recent lower-limb rehabilitation robots.

GroupsDevicesResearchersActuated DoFDriving modesControl strategiesTraining modes

Lokomat [101]Zurich
Switzerland
Two-leg DoFsMotor drivePosition control
Patient-cooperative
strategy
Posture control
Passive mode
Active assist mode
LokoHelp [16]Woodway & LokoHelp GroupTwo-leg DoFsTreadmill drive, standalone
driving device not required
Trajectory tracking
control
Passive mode
Active assist mode
Treadmill-based
exoskeleton robots
ALEX [17]Banala and Aqrawal et al. from
University of Delaware, US
Seven DoFs for translations
and rotation of a leg
Motor driveAssist-as-needed
control
Active mode
Lopes [18, 19]Reneman et al. From university
of Delaware, US
Three rotational DoFs in
each leg
SEA (series elastic actuator)
drive
Impedance
control
Active mode
Active assist mode
AAFO [20]Seoul and Korea from
Yonsei University
Two motion DoFs for
ankle joint
SEA (series elastic actuator)
drive
Force/impedance
control
Active mode
KAFO [21]The Department of Mechanical
Engineering of the Ottawa University
Free motion DoFs in sagittal
plane for ankle and knee
No driver, using the location
of mechanical structure and
spring to provide tailwind
Force controlActive assist mode

Leg orthoses
exoskeleton robots
HAL [22]University of Tsukuba, JapanFull-body exoskeleton for
arms, legs
Motor driveAutonomous control
Automatic mixture
control
Active assist mode
BLEEX [23, 24]Kazeroom et al. from University
of California, US
Seven DoFs for each leg in
hip, knee, and ankle joints
Hydraulic driveEMG signal control
Force control
Passive mode
Rutgers ankle [25]Girone et al. of Rutgers UniversitySix DoFs ankle and foot
based on a Stewart platform
Pneumatic driveImpedance control
Force control
Active mode
Passive mode
Active resist mode

Platform-based
end-effector robots
ARBOT [26, 27]Saglia et al. from Istituto Italiano
di Tecnologia, Italy
Two ankle DoFs in
plantar/dorsiflexion,
inversion/eversion
Motor drivePosition controlPassive mode
Active assist mode
Active resist mode
Parallel ankle
robots [28, 29]
Xie et al. from the University
of Auckland New Zealand
Three ankle DoFs provided
by 4-axis parallel robot
Motor driveEMG-based evaluation
and adaptive control
Active mode
Passive mode
Gait Trainer
GTI [30]
The Free University Berlin,
Germany
Two footplates for foot/leg
movement
Motor driveTrajectory tracking
control
Passive mode
Active mode

Footplate-based
end-effector robots
Haptic
Walker [31]
Hesse et al. from Charite University
Hospital, Germany
Arbitrary movement DoFs
for two feet
Motor driveTrajectory tracking
control
Passive mode
Active mode
G-EO
Systems [32]
Reha Technology AG, SwitzerlandTwo footplates for walking
and climbing DoFs
Motor drivePosition control
Trajectory tracking
control
Active assist mode