OnDeck Validation
Verification and validation is an integral part of simulation. "All software should be assumed guilty until proven innocent", particularly when the software is considered safety critical. Validation is also required to ensure that the model has the required fidelity and is fit for the task.
AVT does its utmost to verify and validate the OnDeck code and helicopter models.
Manufacturers' drawings and data are used to accurately establish undercarriage kinematics and tyre and oleo stiffness and damping component models. Where possible, standalone simulated drop tests are performed to validate the response of the undercarriage. Where correlation is inadequate, optimisation is applied to tune the model.
OnDeck models are subjected to numerous tests to verify that all components are working correctly. These include drop tests, tilt table tests, sliding and toppling tests, wind load and rotor tests, lashing and, where applicable, restraint system tests.
The early 90's saw DSTO performing detailed Seahawk tilt table trials, crane drop tests and embarked testing on a FFG. The development of high fidelity undercarriage models by AVT in 2002 enabled many of the models to be validated against manufacturer’s experimental drop test data. More recently the AVT developed and Commonwealth funded Maritime Helicopter Aid (MHA) system was modified by AVT to enabled the real time validation and tuning of helicopter models. This world first unique capability enables OnDeck models to be fully validated at sea for a wide range of real operating conditions. The system essentially enables the real time overlay of actual and real data (loads, displacements and IMU data).
The MHA capability provides incredible time and cost savings over traditional "test and then analyse" techniques and provides an immediate measure of system performance and the ability to tune the model on the spot in real time to improve correlation. In this way the system provides added assurance that operating limits are safe.
The MHA system has demonstrated this capability as part of New Zealand Seasprite trials and recent ARH Tiger trials (above showing MHA validation). Further detailed in-house AVT tilt table testing is planned as well as further embarked full scale validation.
