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dc.contributor.advisorSinghose, William
dc.contributor.authorPotter, James Jackson
dc.date.accessioned2014-01-13T16:49:00Z
dc.date.available2014-01-13T16:49:00Z
dc.date.created2013-12
dc.date.issued2013-11-18
dc.date.submittedDecember 2013
dc.identifier.urihttp://hdl.handle.net/1853/50342
dc.description.abstractA helicopter can be used to transport a load hanging from a suspension cable. This technique is frequently used in construction, firefighting, and disaster relief operations, among other applications. Unfortunately, the suspended load swings, which makes load positioning difficult and can degrade control of the helicopter. This dissertation investigates the use of input shaping (a command-filtering technique for reducing vibration) to mitigate the load swing problem. The investigation is conducted using two different, but complementary, approaches. One approach studies manual tracking tasks, where a human attempts to make a cursor follow an unpredictably moving target. The second approach studies horizontal repositioning maneuvers on small-scale helicopter systems, including a novel testbed that limits the helicopter and suspended load to move in a vertical plane. Both approaches are used to study how input shaping affects control of a flexible element (the suspended load) and a driven base (the helicopter). In manual tracking experiments, conventional input shapers somewhat degraded control of the driven base but greatly improved control of the flexible element. New input shapers were designed to improve load control without negatively affecting base control. A method for adjusting the vibration-limiting aggressiveness of any input shaper between unshaped and fully shaped was also developed. Next, horizontal repositioning maneuvers were performed on the helicopter testbed using a human-pilot-like feedback controller from the literature, with parameter values scaled to match the fast dynamics of the model helicopter. It was found that some input shapers reduced settling time and peak load swing when applied to Attitude Command or Translational Rate Command response types. When the load was used as a position reference instead of the helicopter, the system was unstable without input shaping, and adding input shaping to a Translational Rate Command was able to stabilize the load-positioning system. These results show the potential to improve the safety and efficiency of helicopter suspended load operations.
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.publisherGeorgia Institute of Technology
dc.subjectHelicopter
dc.subjectInput shaping
dc.subjectCommand filter
dc.subjectSling load
dc.subjectFlexible system
dc.subjectManual control
dc.subjectHuman-in-the-loop control
dc.subjectOperator study
dc.subjectHandling qualities
dc.subjectExperimental platform
dc.subjectDynamic modeling
dc.subject.lcshHelicopters
dc.subject.lcshFlight control
dc.subject.lcshCranes, derricks, etc. Dynamics
dc.subject.lcshFeedback control systems
dc.subject.lcshDamping (Mechanics)
dc.titleInput-shaped manual control of helicopters with suspended loads
dc.typeDissertation
dc.description.degreePh.D.
dc.contributor.departmentMechanical Engineering
thesis.degree.levelDoctoral
dc.contributor.committeeMemberCostello, Mark
dc.contributor.committeeMemberJohnson, Eric
dc.contributor.committeeMemberPritchett, Amy
dc.contributor.committeeMemberWhiteman, Wayne
dc.date.updated2014-01-13T16:49:00Z


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