Page 248 - Handbook of Biomechatronics

244 Georgios A. Bertos and Evangelos G. Papadopoulos

2.1.3 Seamless and Improved Performance
All the different transitions, adjustments and integration of the prosthetic
leg should be seamless, that is, if an amputee wants transition from walk-
ing to running, the prosthesis should recognize this and adapt accordingly
as humans do (Herr et al., 2003). In the same lines, it is recognized that
a coordination of all the tasks to be done (i.e., walking, ascending and
descending slope, siting, dancing, hopping, etc.) is a need and therefore,
the intention of the amputee is important via a high-level controller is of
a paramount importance (Windrich et al., 2016). The walking perfor-
mance of a lower prosthesis of the future should not be inferior to that
of able-bodied walking or other locomotive activities. On the contrary,
prostheses should be designed to overpass human performance. A good
example of this is that amputee runners (called blade runners) with the
spring-leaf-like prosthetic feet at (Bro `ggemann et al., 2008) 100-m sprints
records are very close to the able-bodied runners records with
regular feet (Bro `ggemann et al., 2008; List of IPC world records in
athletics, 2018).

3 NEEDS/VOICE OF CUSTOMER

We have to consider the real needs of the amputees that lower-limb
prostheses have to fill in. This of course depends on the level of amputation.
The transtibial amputees can walk acceptably well with the current prosthe-
ses. They have needs for cosmesis, increased speed of walking, and skin blis-
ters at the socket interface due to high pressure. In addition, they have issues
such as difficulty in ascending and descending stairs, problems with slope
walking, and increased energy consumption especially at faster walking
speeds (Hansen and Starker, 2017; Windrich et al., 2016).
The transfemoral amputees have needs such as leg controllability, proper
shock absorption (shock felt at lower back), increased walking speed, and
symmetry with able-bodied side. In addition, they have issues such as diffi-
culty in ascending and descending stairs, problems with slope walking, and
increased energy consumption (Windrich et al., 2016). Toe clearance during
swing phase is important for transfemoral amputees along with active push
off in late stance phase especially for faster walking speeds. In the case of
bilateral transfemoral, balance and stability issues are of concern (Hansen
and Starker, 2017).