Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The landing phase of any helicopter is the most critical part of the whole flight envelope,
particularly on a moving flight deck. The flight deck is usually located at the stern of the ship,
translating to large heave motions. This thesis focuses on the three fundamental components
required for a successful landing: accurate, relative state-estimation between the helicopter
and the flight deck; a prediction horizon to forecast suitable landing opportunities; and
excellent control to safely unite the helicopter with the flight deck.
A monocular-vision sensor node was developed to provide accurate, relative position and
attitude information of the flight deck. The flight deck is identified by a distinct, geometric
pattern. The relative states are combined with the onboard, kinematic state-estimates of
the helicopter to provide an inertial estimate of the flight deck states. Onboard motion
prediction is executed to forecast a possible safe landing time which is conveyed to the
landing controller.
Camera pose-estimation tests and hardware-in-the-loop simulations proved the system
developed in this thesis viable for flight tests. The practical flight tests confirmed the success
of the monocular-vision sensor node. / AFRIKAANSE OPSOMMING: Die mees kritiese deel van die hele vlug-duurte van ’n helikopter is die landings-fase, veral
op ’n bewegende vlugdek. Die vlugdek is gewoonlik geleë aan die agterstewe-kant van die
skip wat groot afgee bewegings mee bring. Hierdie tesis ondersoek die drie fundamentele
komponente van ’n suksesvolle landing: akkurate, relatiewe toestand-beraming tussen die
helikopter en die vlugdek; ’n vooruitskatting horison om geskikte landings geleenthede te
voorspel; en uitstekended beheer om die helikopter en vlugdek veilig te verenig.
’n Monokulêre-visie sensor-nodus was ontwikkel om akkurate, relatiewe-posisie en oriëntasie
informasie van die vlugdek te verwerf. Die vlugdek is geidentifiseer deur ’n kenmerkende,
geometriese patroon. Die relatiewe toestande word met die aan-boord kinematiese toestandafskatter
van die helikopter gekombineer, om ’n beraming van die inertiale vlugdek-toestande
te verskaf. Aan-boord beweging-vooruitskatting is uitgevoer om moontlike, veilige landingstyd
te voorspel en word teruggevoer na die landingsbeheerder.
Kamera-orientasie afskat-toetse en hardeware-in-die-lus simulasies het die ontwikkelde sisteem
van hierdie tesis lewensvatbaar vir vlug-toetse bewys. Praktiese vlug-toetse het die sukses
van die monokulêre-visie sensor-nodus bevestig.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/80134 |
| Date | 03 1900 |
| Creators | Swart, Andre Dewald |
| Contributors | Peddle, I. K., Stellenbosch University. Faculty of Engineering. Dept. of Electrical and Electronic Engineering. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 114 p. : ill. |
| Rights | Stellenbosch University |
Page generated in 0.0022 seconds