Development and Experimental Validation of a Shipboard Helicopter On-Deck Maneuvering Simulation

Abstract

Routine shipboard helicopter operation on many classes of ships requires that helicopters be maneuvered and traversed along the ship deck using installed helicopter securing and handling equipment. This paper describes the derivation, implementation, and validation of a four-degrees-of-freedom mathematical model for predicting and analyzing the behavior of shipboard aircraft under the influence of external aircraft handling forces. The resulting model is suitable both for engineering analysis and training applications. The helicopter model includes the coupled dynamics of the aircraft, landing gear, and optionally steerable or castorable auxiliary wheel assembly. Detailed tire modeling addresses the transient development and release of tire deflection and cornering forces related to yawed and unyawed relaxation lengths as well as direct application of forces by the handling system. Verification and both qualitative and full-scale experimental validation of the model, performed using a number of simple maneuvers to validate specific aspects of the simulation, are discussed. It is shown that the resulting HeliMan simulation captures the underlying dynamics of the shipboard helicopter maneuvering process. Full-scale validation data show that in many cases the simulation is able to reproduce closely the measured data. The effect of tire side loading on longitudinal rolling resistance has been identified as a shortcoming of existing rolling tire models and the most probable cause for differences that exist between simulated and measured results in some validation cases. NomenclatureA = vector representing the accelerations for the two bodies A C = acceleration vector of the castor assembly A ex = equivalent cross-sectional area of the helicopter for the plane perpendicular to the x plane A ey = equivalent cross-sectional area of the helicopter for the plane perpendicular to the y plane A H = acceleration vector of the main helicopter a = Gauss elimination demonstration matrix B = kinematic matrix C = vector representing the nonlinear components of the kinematic equations C B = coefficient of viscous damping at the castor pivot joint C fix = torsional damping coefficient used to fix the castor assembly C P = probe damping coefficient C ty = tire lateral damping coefficient C tz = vertical tire force constant dependent on the tire type c = Gauss elimination demonstration vector D = matrix used to isolate the unknown forces D Ps = small probe deflection stiffness transition displacement d = vector of tire deflections d ssy = steady-state lateral tire deflection for a given slip angle E = elements of governing dynamic equation forcing vector F = vector containing the sum of generalized forces and moments Aerospace Engineering, 1125 Colonel By Drive; rlangloi@mae.carleton.ca. F a = friction force between axle and wheel F B = force vector acting on the joint pivot point B F c = probe force vector caused by the probe damping F ct 1 = force vector acting on the first (left) castor tire F ct 2 = force vector acting on the seco...

Spacial Simulation of Shipboard Operations for Skid-equipped Rotary-wing Aircraft

“…Accordingly, simulation software specifically targeted at studying the dynamics of shipboard operations for these types of helicopters is available, e.g. HeliMan [1], DYNAFACE ® [2], and SSMASH [3]. With UASs, a different set of challenges is present in shipboard operations.…”

Robotic Strategies to Assist Pilots in Landing and Takeoff of Helicopters on Ships and Offshore

“…Furthermore, an aircraft/ship dynamic interface analysis simulation software package has been developed in order to analyze dynamic interface that exists between ships and embarked aircraft. It has been extensively validated and applied (Linn & Langlois, 2006), (Langlois & LaRosa, 2003). Aircraft performance data is scheduled in the flight manual and/or the operations manual which enables flight crew to accommodate the varying ambient conditions and operate in such a way that the helicopter has sufficient space and engine performance to approach land and take off from helidecks in securely.…”

An Active helideck testbed for floating structures based on a Stewart-Gough platform

“…Furthermore, an aircraft/ship dynamic interface analysis simulation software package has been developed in order to analyze dynamic interface that exists between ships and embarked aircraft. It has been extensively validated and applied [6], [7]. Computer simulations are some approaches done for studying this case.…”