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Biologically Inspired Robotics
a
b
c
d
FIGURE 8.7
Stretching process of a swollen RBC: (a) before stretching, (b) during stretching, (c) stretched to
the maximum deformation, and (d) the bead escapes the laser trap. Scale bar is 5 μm. Reprinted
with permission from IEEE (Tan et al. 2009).
move by the motorized stage, the anchored side of the cell was moved with
the stage. Because the trapped bead was kept fixed in the optical trap, the
RBC was stretched until the trapped bead escaped from the trap. Note that
the moving direction of the stage was determined along the line passing
through the bead’s centroid and the binding site of the cell. Figure 8.7 shows
the cell stretching process.
For each stretching experiment, RBCs were stretched to different levels of
deformation over a range of laser powers, which were recorded by the CCD
camera for image analysis. The image at the moment when the trap could
not hold the bead any longer was captured for cell deformation estimation.
The trapping force can be acquired from the calibrated relationship between
trapping force and laser power. Figure 8.8 shows the stretched cell shapes
under a series of trapping forces. To obtain the deformations of RBCs, the
digital image was processed by a home-built program to detect the edges of
the stretched RBCs as shown in Figure 8.9. Then the axial deformation was
measured.
8.4 Results and Discussion
Cell deformation was measured at each laser power. Then the relationship
between the stretching force and the induced axial deformation was established for cell stretching experiments, which is shown in Figure 8.10. For each
data point, ten separate tests were conducted and the obtained results were
Biologically Inspired Robotics
a
b
c
d
FIGURE 8.7
Stretching process of a swollen RBC: (a) before stretching, (b) during stretching, (c) stretched to
the maximum deformation, and (d) the bead escapes the laser trap. Scale bar is 5 μm. Reprinted
with permission from IEEE (Tan et al. 2009).
move by the motorized stage, the anchored side of the cell was moved with
the stage. Because the trapped bead was kept fixed in the optical trap, the
RBC was stretched until the trapped bead escaped from the trap. Note that
the moving direction of the stage was determined along the line passing
through the bead’s centroid and the binding site of the cell. Figure 8.7 shows
the cell stretching process.
For each stretching experiment, RBCs were stretched to different levels of
deformation over a range of laser powers, which were recorded by the CCD
camera for image analysis. The image at the moment when the trap could
not hold the bead any longer was captured for cell deformation estimation.
The trapping force can be acquired from the calibrated relationship between
trapping force and laser power. Figure 8.8 shows the stretched cell shapes
under a series of trapping forces. To obtain the deformations of RBCs, the
digital image was processed by a home-built program to detect the edges of
the stretched RBCs as shown in Figure 8.9. Then the axial deformation was
measured.
8.4 Results and Discussion
Cell deformation was measured at each laser power. Then the relationship
between the stretching force and the induced axial deformation was established for cell stretching experiments, which is shown in Figure 8.10. For each
data point, ten separate tests were conducted and the obtained results were