D2.1 Requirements and Specification - CORBYS

D2.1 Requirements and Specification
Figure 5: Stiff knee gait with circumduction in sagittal plane (top) and in frontal plane (bottom)
Principal characteristics of stiff knee walking with circumduction are:
� inadequate knee flexion throughout the gait cycle
� excessive dorsiflexion
� inadequate knee flexion stimulates contralateral trunk tilt and pelvic vertical movement to assure
sufficient foot clearance
They impose:
� insecure and unstable weight transfer due to constant knee extension
� propulsion is achieved predominantly by rapid hip extension instead of forceful extension in all joints
� combined excessive pelvic vertical movement and hip adduction in swing phase compensates the
lacking knee flexion to assure sufficient foot clearance
CORBYS system should restore:
� normal knee flexion to allow secure and stable weight transfer in initial contact and midstance
� forceful extension in ankle, knee and hip during push off to assure normal propulsion
� normal knee flexion to assure sufficient foot clearance (excessive pelvic vertical movement and hip
adduction will no longer be necessary)
4.2 Environment of the demonstrator I: gait rehabilitation user­robot
interaction
CORBYS demonstrator should be an institution-based gait locomotion rehabilitation training instrument. It
should be an intelligent gait rehabilitation device; a mobile gait trainer. Patients could be treated both as
inpatients and outpatients. The system could be integrated in the treatment workflow of a rehabilitation
department which is illustrated in Figure 6.
The gait rehabilitation robotic system could be integrated in this workflow in the following way:
- The patient´s gait is analysed on admission on a treadmill with sensors measuring kinematics, forces
and resistance in hip, knee and ankle joint as well as force on ground via foot plates parts. The CORBYS
11