Page 224 - Handbook of Biomechatronics

Upper-Limb Prosthetic Devices 221

2.7.1 Biomechanics Model
Since the long-term vision for the upper-limb field is a multi-DoF control
including both motor pathways (efferent) and sensory (afferent) pathways
integration, a good biomechanics model connecting all the control inputs
to prosthesis DoFs should be needed in the future. Several attempts have
been made but without a satisfactory and stable result up to now. The latest
most successful and unsuccessful attempt for the development of such a sta-
ble model is made by Blana et al. (2016) and (2017). This is a research area
that will be needed in the future in order for multi-DoF prostheses to
become functional and available.

2.7.2 Peripheral Nerve Stimulation
The peripheral nerve stimulation that has been integrated with prosthetic
arms in the recent years has positioned the upper-limb prostheses to be more
integratable with the amputee, since the person “feels” the status of the envi-
ronment in a natural proprioceptive way.
The existence of peripheral motor and sensory pathways and their sat-
isfactory functionality has been demonstrated for after 2years after ampu-
tation surgery and after any CNS reorganization (Dhillonetal.,2004).
Longitudinal intrafascicular electrodes (LIFEs) electrodes implanted in
upper-limb amputees connected to force and position sensors of a prosthe-
sis have been used to set grip forces, leading to increased performance and
natural integration of the prosthetic arm with the amputee (Dhillon and
Horch, 2005).
The group at Case Western Reserve University, a Center for Functional
Electrical Stimulation, has developed a cuff-like, flat interface nerve elec-
trode (FINE), which has the advantage that is not penetrating the nerves
but on the contrary it forms a surface where the nerves are reshaped upon
(Tyler and Durand, 2002). A recent study on two upper-limb amputees that
the FINE electrodes are stable, selective with repeatable responses for up to
24months (Tan et al., 2014)(Fig. 23). Adjusting the average intensity of the
stimulation affects the perception area. Adjusting the frequency of the stim-
ulation affects the perception strength (Tan et al., 2014). When these elec-
trodes were connected with force sensors at the tip of a prosthetic hand,
increased manipulation performance of delicate objects (cherries) was
observed (Tan et al., 2014).
The Biorobotics Institute at Scuole Superiore Sant’ Anna (SSSA) used
prototype transverse intrafascicular multichannel electrodes (TIME)
(Boretius et al., 2010; Stieglitz et al., 2012; Badia et al., 2016) and a