# HAC-HAC - My digital brain
Tags : High-Authority Control/Low-Authority Control From (Andre Preumont, 2018): The HAC/LAC approach consist of combining the two approached in a dual-loop control as shown in Figure 1. The inner loop uses a set of collocated actuator/sensor pairs for decentralized active damping with guaranteed stability ; the outer loop consists of a non-collocated HAC based on a model of the actively damped structure. This approach has the following advantages: The active damping extends outside the bandwidth of the HAC and reduces the settling time of the modes which are outsite the bandwidth The active [cut: 854 characters, first 598 kept]
Author: — Thomas Dehaeze

# HAC-HAC

Tags :

High-Authority Control/Low-Authority Control

From (Andre Preumont, 2018):

> The HAC/LAC approach consist of combining the two approached in a dual-loop control as shown in Figure 1. The inner loop uses a set of collocated actuator/sensor pairs for decentralized active damping with guaranteed stability ; the outer loop consists of a non-collocated HAC based on a model of the actively damped structure. This approach has the following advantages:

> - The active damping extends outside the bandwidth of the HAC and reduces the settling time of the modes which are outsite the bandwidth
> - The active damping makes it easier to gain-stabilize the modes outside the bandwidth of the output loop (improved gain margin)
> - The larger damping of the modes within the controller bandwidth makes them more robust to the parmetric uncertainty (improved phase margin)

Figure 1: HAC-LAC Control Architecture

# Bibliography

Preumont, A., Vibration control of active structures - fourth edition (2018), : Springer International Publishing. ↩