English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Shape memory alloys (SMA) exhibit many positive characteristics for application in smart structures. Control of SMA actuators has typically been limited by their non­ linear behaviour. Actuators using SMA are restricted to low frequency applications due to the necessary cooling times. Nevertheless, SMA actuators are applied for active control systems within experimental aerospace vehicles. This thesis is an investigation of SMA actuator wires for control of a shaft angle. A review of SMA actuator applications and actively controlled helicopter rotor blades is presented. Experiments performed to determine the characteristics of the Flexinol SMA wire are then discussed. Control of the shaft is demonstrated using a single actuator wire and bias load, and two antagonistic wires. Casual control algorithms developed to successfully follow a target angle and reject random disturbances are presented. A comparison is made between experimental data and mathematical models. Finally, the use of SMA actuator wires for control of an active helicopter blade tip is studied for feasibility.

Investigation of shape memory alloy wire for closed loop angular position control of a shaft under random excitation