digital-brain/content/zettels/hac_hac.md

+++ title = "HAC-HAC" author = ["Thomas Dehaeze"] draft = false +++

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 src="/ox-hugo/hac_lac_control_architecture.png" caption="Figure 1: HAC-LAC Control Architecture" >}}

Nice papers:

• ^{(Williams & Antsaklis, 1989)}
• ^{(Aubrun, 1980)}

Bibliography

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

Williams, T., & Antsaklis, P., Limitations of vibration suppression in flexible space structures, In , Proceedings of the 28th IEEE Conference on Decision and Control (pp. ) (1989). : . ↩

Aubrun, J., Theory of the control of structures by low-authority controllers, Journal of Guidance and Control, 3(5), 444–451 (1980). http://dx.doi.org/10.2514/3.56019 ↩

Backlinks

• [Control of spacecraft and aircraft]({{< relref "bryson93_contr_spacec_aircr" >}})
• [Vibration Control of Active Structures - Fourth Edition]({{< relref "preumont18_vibrat_contr_activ_struc_fourt_edition" >}})