![](bg6.png)
Figure 9: The amplitude of the arm movement, θ (in stars),
and of the applied electrical stimulation (triangles) as a
function of time. The stimulation frequencies were 30Hz
(Top) and 50Hz (Bottom).
5 CONCLUSIONS
This article presents an inexpensive small-sized
transcutaneous electrical stimulator unit capable of
integrating feedback information arising from a
digital accelerometer with electrostimulation. The
delivered pulsed currents can be controlled in real
time and according to a programmed protocol, on a
number of parameters - pulse duration and
amplitude, pulse rate, the type of current modulation
(burst, interrupt or ramp modulation).
In the future more elaborate ES programs should
be developed to deliver optimal ES adjusted to a
patient’s needs. These programmes can use higher
computational power and sophisticated theoretical
models of muscle function, to design the most
efficient ES programmes.
ACKNOWLEDGEMENTS
This work was supported by FCT project RIPD /
SAU-OBS / 63630 / 2005. ED is supported by FCT
SFRH / BD / 31218 / 2006.
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