ATMDSAlpha-Thalassemia Myelodysplasia Syndrome
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The control strategy of an ATMD is at the core of research in this technology.
From the schematic of an ATMD-vibration damping system (Figure 1), the ATMD is mounted on the main system.
The force f acting between the ATMD and the main system is measured in real time using a piezoelectric force sensor.
where [x.sub.a] and [x.sub.p] represent the vibration displacements of the ATMD mass block and main system, respectively.
Equation (8) determines the force feedback control strategy of the ATMD. As G(s) has a pole at s = 0 that affects the system stability, a nonzero pole needs to be established to improve the stability.
The ATMD power consumption is also a factor that needs to be considered in the design.
In general, V of the ATMD mass is much greater than [V.sub.p], so the second term in (10) can be ignored.
Figure 4 shows the damping curves for the ATMD with the natural frequency set at 30 Hz, 40 Hz, and 50 Hz in the main system.
Figure 5 shows a comparison of the ATMD damping when different natural frequencies are set by setting the mass to 0.5 kg, 1 kg, and 2 kg in the main system.
Analysis of Power Consumption Required by the ATMD. Power consumption strongly reflects the nature of the stroke and active force.
For vector X, [X.sub.a] and [X.sub.b] are, respectively, the Laplace transforms of the vibration displacements at the ATMD and the ATMD installation points.
where [f.sub.act] is the active control force and [X.sub.a] is the vibration displacement of the ATMD mass block.