A new device for hand rehabilitation of stroke patient is presented. Its main innovative features are: lightness, real safety guaranteed by its structural elasticity, smoothness and easiness of movements. The kinematic behavior of the system hand-plus-rehabilitation-device is analyzed. The device applicability is confirmed by positive testing.
Cerebrovascular diseases are the third cause of mortality and the second cause of long term disability in Western countries. The 60% of survived individuals shows a sensitive/motor deficit of one or both hands and must be subjected to a rehabilitative treatment to recover the use of the upper limb.
Recent technologies have facilitated the use of robots as assistive tools to patients, providing safe and highly personalized rehabilitation sessions, thus making therapist contribution to recovery much more intensive and effective.
We propose in this work a wearable glove with an incorporated compliant mechanical transmission over the hand.
The glove is composed by two main modules with well-defined mechanical characteristics. One is the actuator on the upper side of the forearm, close to the wrist (and to the impaired hand) and still separated from it; the other (the transmission) is composed by several elastic transmissions which, moved by the actuator, properly transmit displacements, speed and forces to one or more impaired fingers during a rehabilitation session. While the actuator module has a rigid and defined structure and is fixed to the forearm section of the glove, the “transmission” module has in fact a labile and extended structure as it has to reach all five fingers (one, some, or all might be impaired and in need of rehabilitation) up to their tips and move them in an effective and reliable way.
A kinematical characterization of the compliant transmission is proposed to dimension the actuators and to define the correct commanded motion profile at actuator level.