Biomedical Engineering Reference
In-Depth Information
Figure 11.9
Muscle strengthening and evaluation machine.
Table 11.2
Definitions of each
parameter for velocity controller.
K
P
:
0.5Nms/rad
K
I
:
100Nm/rad
11.4.2 Experimental Method
Figure 11.9
s
hows how experiments were conducted. In this paper, we will focus
on the elbow flexion and fully extended elbow is defined as 0[deg]. The user,
strapped in a chair, flexes an elbow at an initial angle of 45[deg] and a final angle
of 140[deg]. The elbow can be flexed at any time when the user likes to maximize
strength. Brake force is adjusted so that the system maintains a set speed.
Experiments were conducted by three subjects with different maximum devel-
their dominant hands in experiments.
11.4.3 Experimental Results
Reference velocity was increased in steps of 100deg/s from 0 to 900 deg/s.
Figs.
commanded values and solid lines measurement results indicating that stable,
accurate control was achieved for references. When a brake is used for passive
velocity control, drive torque is provided by the developmental torque of subjects.
When the elbow is flexed in a range of angles between 45deg and 140deg, periods