Abstract:
This paper proposes a hip exoskeleton robot named
HipExo to provide power assistance for the industrial workers
during stoop lifting activities. It introduces a hybrid actuator
to power the hip joints. The electric motor and transmission is
coupled to a spring system that can store biomechanical energy
during the descent phase and release the stored energy during
the ascent phase of the lifting cycle. Furthermore, the robot is
comprised of flexible upper body linkage mechanism capable of
adapting to the lumbar curvature and assuming the shape of
the trunk. A mathematical model is formulated to estimate the
hip torque profile for the stoop lifting cycle. Moreover, a torque
control approach was introduced to control the robot according
to the motion intentions of the user. The experimental results
reveal that HipExo is effective in reducing muscle activity during
stoop lifting and it has the potential of alleviating lift-related
musculoskeletal disorders.
