Biomedical Engineering Reference
In-Depth Information
A
C
B
B
D
B
E
E
M
E
D
D
FIGURE 9.2
The three-dimensional IPMNC actuator concept.
long edges and having three external faces,
B
. The tube is fixed to the generator box
M
. One pair of terminals,
D
, is located on each of the three actuators
C
for connection
to electrodes
E
incorporated in generator box
M
.
is designed to produce a three-dimensional movement
by positioning each of the actuators to be stimulated at a phase angle apart from the
adjacent actuator by a low-amplitude alternating signal, therefore inducing wobble-
like motion around the long imaginary axis of the combined actuator tube in null
position. Each IPMNC actuator has its own terminal connections to each phase of a
typical three-phase power generator (
The IPMNC actuator
C
) or a multiphase power supply (programmable
function generators/power supplies exist that have phase-separated outputs). Figure
9.2 details this arrangement. Each of these IPMNC actuators has its external and
internal faces similar to the top and bottom faces of the gripper shown in figure 9.1.
Other configurations of three-dimensional motion actuators, such as the four-
sided square rod shown in figure 9.3 and undulating and morphing actuators shown
in figure 9.4, are also possible. Motion produced by any such device would be used
to power soft mixers, production line feeders, and other task-specific equipment for
many industrial usages. Also, in sensing modes, they can be used as joysticks or
X-Y locators.
M
9.2.3
R
S
S
OBOTIC
WIMMING
TRUCTURE
Figure 9.5 shows one embodiment of a robotic swimming structure made by cutting
and packaging strips of IPMNCs
to desired size and shape and consequently
placing an alternating low voltage (a few volts' peak per strip) across the muscle
assembly
A
E
. In this figure, muscle assembly
E
is formed of IPMNC strips
B
encap-
sulated into an elastic membrane
C
with electrodes
D
imprinted on each strip there
and with a first end and a second end. Second end
F
is attached to an appropriate
electronics and wiring structure
G
for providing guidance and control to actuate the
