Page 184 - Robot Builders Source Book - Gordon McComb

172 Kinematics and Control of Automatic Machines

FIGURE 4.71 Active damping force generator.
1) Oscillating mass; 2) Core of the magnet;
3) Coil of the magnet; 4) Armature.

FIGURE 4.72 Comparison of the free oscillation of mass M
(computation) without (damping takes about 20 sec) and
with actuation of the AD (damping takes about 10 sec).

force is applied to the mass M. Obviously, the bigger the mass of the armature 4, the
bigger the force.
The core 4 is fastened to the arm of the manipulator (or any other object).
An example of a comparison of the vibrations damping processes is shown in Figure
4.72. One process, taking about 20 seconds, is calculated for a usual system, without
any artificial damping means, while the other, taking about 11 seconds, is the result
of AD use.
A special control system that carries out all signal transformations must be used
for this method. Its general layout for one control channel is shown in Figure 4.73. The
accelerometer and the active damper are placed on the end of a robot's arm. The signal

FIGURE 4.73 Layout of the proposed AD system.
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